Move network_graph.rs to gossip.rs
authorJeffrey Czyz <jkczyz@gmail.com>
Thu, 2 Jun 2022 19:53:34 +0000 (12:53 -0700)
committerJeffrey Czyz <jkczyz@gmail.com>
Thu, 2 Jun 2022 22:15:30 +0000 (15:15 -0700)
The routing::network_graph module contains a few structs related to p2p
gossip. So renaming the module to 'gossip' seems more appropriate.

25 files changed:
fuzz/src/full_stack.rs
fuzz/src/process_network_graph.rs
fuzz/src/router.rs
lightning-background-processor/src/lib.rs
lightning-invoice/src/de.rs
lightning-invoice/src/lib.rs
lightning-invoice/src/payment.rs
lightning-invoice/src/utils.rs
lightning-invoice/tests/ser_de.rs
lightning-rapid-gossip-sync/src/lib.rs
lightning-rapid-gossip-sync/src/processing.rs
lightning/src/ln/channelmanager.rs
lightning/src/ln/functional_test_utils.rs
lightning/src/ln/mod.rs
lightning/src/ln/onion_route_tests.rs
lightning/src/ln/onion_utils.rs
lightning/src/ln/peer_handler.rs
lightning/src/ln/priv_short_conf_tests.rs
lightning/src/routing/gossip.rs [new file with mode: 0644]
lightning/src/routing/mod.rs
lightning/src/routing/network_graph.rs [deleted file]
lightning/src/routing/router.rs
lightning/src/routing/scoring.rs
lightning/src/util/events.rs
lightning/src/util/persist.rs

index 1c9c590f8bbf7dde61692ed8548bb53e4eb7b259..a59d78e1c54cc35507b2ec4d0f3a66fb0753a01a 100644 (file)
@@ -37,7 +37,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelManager};
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::DecodeError;
 use lightning::ln::script::ShutdownScript;
-use lightning::routing::network_graph::{P2PGossipSync, NetworkGraph};
+use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::router::{find_route, PaymentParameters, RouteParameters};
 use lightning::routing::scoring::FixedPenaltyScorer;
 use lightning::util::config::UserConfig;
index a71ae0e221b294cb302960d34bc4f6e966fa8124..118862569d039b47ea967c79207c463bbbe837f6 100644 (file)
@@ -5,7 +5,7 @@ use utils::test_logger;
 /// Actual fuzz test, method signature and name are fixed
 fn do_test(data: &[u8]) {
        let block_hash = bitcoin::BlockHash::default();
-       let network_graph = lightning::routing::network_graph::NetworkGraph::new(block_hash);
+       let network_graph = lightning::routing::gossip::NetworkGraph::new(block_hash);
        let rapid_sync = RapidGossipSync::new(&network_graph);
        let _ = rapid_sync.update_network_graph(data);
 }
index 9f4fd512ca25a9e4112d20588edfa149ad235cc7..ec12ff7e144e4708670ccc3aea79cd91d1201247 100644 (file)
@@ -16,11 +16,11 @@ use lightning::chain::transaction::OutPoint;
 use lightning::ln::channelmanager::{ChannelDetails, ChannelCounterparty};
 use lightning::ln::features::InitFeatures;
 use lightning::ln::msgs;
+use lightning::routing::gossip::{NetworkGraph, RoutingFees};
 use lightning::routing::router::{find_route, PaymentParameters, RouteHint, RouteHintHop, RouteParameters};
 use lightning::routing::scoring::FixedPenaltyScorer;
 use lightning::util::logger::Logger;
 use lightning::util::ser::Readable;
-use lightning::routing::network_graph::{NetworkGraph, RoutingFees};
 
 use bitcoin::hashes::Hash;
 use bitcoin::secp256k1::PublicKey;
index 9783f9e7ebc2a5d31b3f4d76220eea104a9a7125..2e947a7041afdd92c4c8ac86c053c6781de24f26 100644 (file)
@@ -18,7 +18,7 @@ use lightning::chain::keysinterface::{Sign, KeysInterface};
 use lightning::ln::channelmanager::ChannelManager;
 use lightning::ln::msgs::{ChannelMessageHandler, RoutingMessageHandler};
 use lightning::ln::peer_handler::{CustomMessageHandler, PeerManager, SocketDescriptor};
-use lightning::routing::network_graph::{NetworkGraph, P2PGossipSync};
+use lightning::routing::gossip::{NetworkGraph, P2PGossipSync};
 use lightning::routing::scoring::WriteableScore;
 use lightning::util::events::{Event, EventHandler, EventsProvider};
 use lightning::util::logger::Logger;
@@ -162,8 +162,8 @@ impl BackgroundProcessor {
        /// [`ChannelManager::write`]: lightning::ln::channelmanager::ChannelManager#impl-Writeable
        /// [`Persister::persist_manager`]: lightning::util::persist::Persister::persist_manager
        /// [`Persister::persist_graph`]: lightning::util::persist::Persister::persist_graph
-       /// [`NetworkGraph`]: lightning::routing::network_graph::NetworkGraph
-       /// [`NetworkGraph::write`]: lightning::routing::network_graph::NetworkGraph#impl-Writeable
+       /// [`NetworkGraph`]: lightning::routing::gossip::NetworkGraph
+       /// [`NetworkGraph::write`]: lightning::routing::gossip::NetworkGraph#impl-Writeable
        pub fn start<
                'a,
                Signer: 'static + Sign,
@@ -408,7 +408,7 @@ mod tests {
        use lightning::ln::features::{ChannelFeatures, InitFeatures};
        use lightning::ln::msgs::{ChannelMessageHandler, Init};
        use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
-       use lightning::routing::network_graph::{NetworkGraph, P2PGossipSync};
+       use lightning::routing::gossip::{NetworkGraph, P2PGossipSync};
        use lightning::util::config::UserConfig;
        use lightning::util::events::{Event, MessageSendEventsProvider, MessageSendEvent};
        use lightning::util::ser::Writeable;
index e9b639c101307dccd7e229caee1303c77a0bbca6..b4eb04a3d21666369fb6956ca026aebcf8e44496 100644 (file)
@@ -13,7 +13,7 @@ use bitcoin_hashes::Hash;
 use bitcoin_hashes::sha256;
 use crate::prelude::*;
 use lightning::ln::PaymentSecret;
-use lightning::routing::network_graph::RoutingFees;
+use lightning::routing::gossip::RoutingFees;
 use lightning::routing::router::{RouteHint, RouteHintHop};
 
 use num_traits::{CheckedAdd, CheckedMul};
@@ -909,7 +909,7 @@ mod test {
 
        #[test]
        fn test_parse_route() {
-               use lightning::routing::network_graph::RoutingFees;
+               use lightning::routing::gossip::RoutingFees;
                use lightning::routing::router::{RouteHint, RouteHintHop};
                use ::PrivateRoute;
                use bech32::FromBase32;
index 008d3344b55c5f2becae9cfd553d1c3f3f84dc2a..609b33b2d50d941f74585addc5cdd7565fb348fb 100644 (file)
@@ -45,7 +45,7 @@ use bitcoin_hashes::sha256;
 use lightning::ln::PaymentSecret;
 use lightning::ln::features::InvoiceFeatures;
 #[cfg(any(doc, test))]
-use lightning::routing::network_graph::RoutingFees;
+use lightning::routing::gossip::RoutingFees;
 use lightning::routing::router::RouteHint;
 use lightning::util::invoice::construct_invoice_preimage;
 
index c095f74dd16e2e0dc9c3c41dacf7122c75e179a9..e672b89c919c4aefaa6cb1c7bb6074bf54059941 100644 (file)
@@ -38,7 +38,7 @@
 //! # use lightning::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
 //! # use lightning::ln::channelmanager::{ChannelDetails, PaymentId, PaymentSendFailure};
 //! # use lightning::ln::msgs::LightningError;
-//! # use lightning::routing::network_graph::NodeId;
+//! # use lightning::routing::gossip::NodeId;
 //! # use lightning::routing::router::{Route, RouteHop, RouteParameters};
 //! # use lightning::routing::scoring::{ChannelUsage, Score};
 //! # use lightning::util::events::{Event, EventHandler, EventsProvider};
@@ -602,7 +602,7 @@ mod tests {
        use lightning::ln::features::{ChannelFeatures, NodeFeatures, InitFeatures};
        use lightning::ln::functional_test_utils::*;
        use lightning::ln::msgs::{ChannelMessageHandler, ErrorAction, LightningError};
-       use lightning::routing::network_graph::NodeId;
+       use lightning::routing::gossip::NodeId;
        use lightning::routing::router::{PaymentParameters, Route, RouteHop};
        use lightning::routing::scoring::ChannelUsage;
        use lightning::util::test_utils::TestLogger;
index 9f6691564ca64399b9e3299096783248187bc043..04cfb3f147099181b37ed8e6dee70d989f983233 100644 (file)
@@ -15,9 +15,9 @@ use lightning::ln::channelmanager::{ChannelDetails, ChannelManager, PaymentId, P
 use lightning::ln::channelmanager::{PhantomRouteHints, MIN_CLTV_EXPIRY_DELTA};
 use lightning::ln::inbound_payment::{create, create_from_hash, ExpandedKey};
 use lightning::ln::msgs::LightningError;
-use lightning::routing::scoring::Score;
-use lightning::routing::network_graph::{NetworkGraph, RoutingFees};
+use lightning::routing::gossip::{NetworkGraph, RoutingFees};
 use lightning::routing::router::{Route, RouteHint, RouteHintHop, RouteParameters, find_route};
+use lightning::routing::scoring::Score;
 use lightning::util::logger::Logger;
 use secp256k1::PublicKey;
 use core::ops::Deref;
index 1d9c481513dd98944514fd25ea2f7601b2e935a2..ffac702ce1a99582f42ae75e2e26cf7af98f8f6d 100644 (file)
@@ -9,8 +9,8 @@ use bitcoin_hashes::hex::FromHex;
 use bitcoin_hashes::{sha256, Hash};
 use bech32::u5;
 use lightning::ln::PaymentSecret;
+use lightning::routing::gossip::RoutingFees;
 use lightning::routing::router::{RouteHint, RouteHintHop};
-use lightning::routing::network_graph::RoutingFees;
 use lightning_invoice::*;
 use secp256k1::PublicKey;
 use secp256k1::ecdsa::{RecoverableSignature, RecoveryId};
index d07a19fda43333a170086d7144d8488ea6163382..278cede397411720415b89d20a6c9ccaecb1160d 100644 (file)
@@ -29,7 +29,7 @@
 //! ```
 //! use bitcoin::blockdata::constants::genesis_block;
 //! use bitcoin::Network;
-//! use lightning::routing::network_graph::NetworkGraph;
+//! use lightning::routing::gossip::NetworkGraph;
 //! use lightning_rapid_gossip_sync::RapidGossipSync;
 //!
 //! let block_hash = genesis_block(Network::Bitcoin).header.block_hash();
@@ -62,7 +62,7 @@ use std::fs::File;
 use std::ops::Deref;
 use std::sync::atomic::{AtomicBool, Ordering};
 
-use lightning::routing::network_graph::NetworkGraph;
+use lightning::routing::gossip::NetworkGraph;
 
 use crate::error::GraphSyncError;
 
@@ -127,7 +127,7 @@ mod tests {
        use bitcoin::Network;
 
        use lightning::ln::msgs::DecodeError;
-       use lightning::routing::network_graph::NetworkGraph;
+       use lightning::routing::gossip::NetworkGraph;
        use crate::RapidGossipSync;
 
        #[test]
@@ -253,7 +253,7 @@ pub mod bench {
        use bitcoin::Network;
 
        use lightning::ln::msgs::DecodeError;
-       use lightning::routing::network_graph::NetworkGraph;
+       use lightning::routing::gossip::NetworkGraph;
 
        use crate::RapidGossipSync;
 
index 6ffc6f58ea88bf6adbf1fc9e7fbd2184a0ed78e4..21c1ce29a99142f427dd8f9947f8fe0c94cfbcfa 100644 (file)
@@ -10,7 +10,7 @@ use bitcoin::secp256k1::PublicKey;
 use lightning::ln::msgs::{
        DecodeError, ErrorAction, LightningError, OptionalField, UnsignedChannelUpdate,
 };
-use lightning::routing::network_graph::NetworkGraph;
+use lightning::routing::gossip::NetworkGraph;
 use lightning::util::ser::{BigSize, Readable};
 
 use crate::error::GraphSyncError;
@@ -235,7 +235,7 @@ mod tests {
        use bitcoin::Network;
 
        use lightning::ln::msgs::DecodeError;
-       use lightning::routing::network_graph::NetworkGraph;
+       use lightning::routing::gossip::NetworkGraph;
 
        use crate::error::GraphSyncError;
        use crate::RapidGossipSync;
index cb2381f9c04a403e48d9ffce4338a77be6aa6036..1d43fa0a460f96ec33a9a5d094a72fb9884ac53c 100644 (file)
@@ -7567,7 +7567,7 @@ pub mod bench {
        use ln::features::{InitFeatures, InvoiceFeatures};
        use ln::functional_test_utils::*;
        use ln::msgs::{ChannelMessageHandler, Init};
-       use routing::network_graph::NetworkGraph;
+       use routing::gossip::NetworkGraph;
        use routing::router::{PaymentParameters, get_route};
        use util::test_utils;
        use util::config::UserConfig;
index 48656c81e02eab86e956acf7b3952c9889e75823..594f02fc52e040e4981c312c8b2cf0e93078d08d 100644 (file)
@@ -15,7 +15,7 @@ use chain::channelmonitor::ChannelMonitor;
 use chain::transaction::OutPoint;
 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
 use ln::channelmanager::{ChainParameters, ChannelManager, ChannelManagerReadArgs, RAACommitmentOrder, PaymentSendFailure, PaymentId, MIN_CLTV_EXPIRY_DELTA};
-use routing::network_graph::{P2PGossipSync, NetworkGraph};
+use routing::gossip::{P2PGossipSync, NetworkGraph};
 use routing::router::{PaymentParameters, Route, get_route};
 use ln::features::{InitFeatures, InvoiceFeatures};
 use ln::msgs;
@@ -1506,13 +1506,13 @@ macro_rules! expect_payment_failed_conditions {
 
                                if let Some(chan_closed) = $conditions.expected_blamed_chan_closed {
                                        match network_update {
-                                               &Some($crate::routing::network_graph::NetworkUpdate::ChannelUpdateMessage { ref msg }) if !chan_closed => {
+                                               &Some($crate::routing::gossip::NetworkUpdate::ChannelUpdateMessage { ref msg }) if !chan_closed => {
                                                        if let Some(scid) = $conditions.expected_blamed_scid {
                                                                assert_eq!(msg.contents.short_channel_id, scid);
                                                        }
                                                        assert_eq!(msg.contents.flags & 2, 0);
                                                },
-                                               &Some($crate::routing::network_graph::NetworkUpdate::ChannelFailure { short_channel_id, is_permanent }) if chan_closed => {
+                                               &Some($crate::routing::gossip::NetworkUpdate::ChannelFailure { short_channel_id, is_permanent }) if chan_closed => {
                                                        if let Some(scid) = $conditions.expected_blamed_scid {
                                                                assert_eq!(short_channel_id, scid);
                                                        }
index 932ca70b00f1f9cf22a47f51cd79beaff5bc54dc..9522e83d18d1cbfa02ddcbe9d0b7ef91ba2d4925 100644 (file)
@@ -19,7 +19,7 @@
 //! call into your [`P2PGossipSync`].
 //!
 //! [`ChannelManager`]: channelmanager::ChannelManager
-//! [`P2PGossipSync`]: crate::routing::network_graph::P2PGossipSync
+//! [`P2PGossipSync`]: crate::routing::gossip::P2PGossipSync
 
 #[cfg(any(test, feature = "_test_utils"))]
 #[macro_use]
index 1c3203edad8b470cc3f6010379d89cd18bb7cce6..eabd2222078b5a73c7456db15d65ff453a45ab05 100644 (file)
@@ -16,7 +16,7 @@ use chain::keysinterface::{KeysInterface, Recipient};
 use ln::{PaymentHash, PaymentSecret};
 use ln::channelmanager::{HTLCForwardInfo, CLTV_FAR_FAR_AWAY, MIN_CLTV_EXPIRY_DELTA, PendingHTLCInfo, PendingHTLCRouting};
 use ln::onion_utils;
-use routing::network_graph::{NetworkUpdate, RoutingFees, NodeId};
+use routing::gossip::{NetworkUpdate, RoutingFees, NodeId};
 use routing::router::{get_route, PaymentParameters, Route, RouteHint, RouteHintHop};
 use ln::features::{InitFeatures, InvoiceFeatures, NodeFeatures};
 use ln::msgs;
index 02676b73bd81f8cfb5edb48281726997ac0b2f55..1df374d7e007b8784d7235c0a216fea4679d408e 100644 (file)
@@ -11,7 +11,7 @@ use ln::{PaymentHash, PaymentPreimage, PaymentSecret};
 use ln::channelmanager::HTLCSource;
 use ln::msgs;
 use ln::wire::Encode;
-use routing::network_graph::NetworkUpdate;
+use routing::gossip::NetworkUpdate;
 use routing::router::RouteHop;
 use util::chacha20::{ChaCha20, ChaChaReader};
 use util::errors::{self, APIError};
index 160c397bd9bdeea44fe8197ad3b9b3a638dff0fd..d86cddb13dbc66162c52af7128f0c3c180688532 100644 (file)
@@ -25,10 +25,10 @@ use util::ser::{VecWriter, Writeable, Writer};
 use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
 use ln::wire;
 use ln::wire::Encode;
+use routing::gossip::{NetworkGraph, P2PGossipSync};
 use util::atomic_counter::AtomicCounter;
 use util::events::{MessageSendEvent, MessageSendEventsProvider};
 use util::logger::Logger;
-use routing::network_graph::{NetworkGraph, P2PGossipSync};
 
 use prelude::*;
 use io;
@@ -210,7 +210,7 @@ pub struct MessageHandler<CM: Deref, RM: Deref> where
        /// A message handler which handles messages updating our knowledge of the network channel
        /// graph. Usually this is just a [`P2PGossipSync`] object or an [`IgnoringMessageHandler`].
        ///
-       /// [`P2PGossipSync`]: crate::routing::network_graph::P2PGossipSync
+       /// [`P2PGossipSync`]: crate::routing::gossip::P2PGossipSync
        pub route_handler: RM,
 }
 
index 81bedbabb479241259efd67cb46295e946cb9a75..13f66805b74b62a9ba66d75cf8384a8a6f567698 100644 (file)
@@ -15,7 +15,7 @@ use chain::{ChannelMonitorUpdateErr, Watch};
 use chain::channelmonitor::ChannelMonitor;
 use chain::keysinterface::{Recipient, KeysInterface};
 use ln::channelmanager::{ChannelManager, ChannelManagerReadArgs, MIN_CLTV_EXPIRY_DELTA};
-use routing::network_graph::RoutingFees;
+use routing::gossip::RoutingFees;
 use routing::router::{PaymentParameters, RouteHint, RouteHintHop};
 use ln::features::{InitFeatures, InvoiceFeatures};
 use ln::msgs;
diff --git a/lightning/src/routing/gossip.rs b/lightning/src/routing/gossip.rs
new file mode 100644 (file)
index 0000000..52cda71
--- /dev/null
@@ -0,0 +1,2771 @@
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
+//! The top-level network map tracking logic lives here.
+
+use bitcoin::secp256k1::constants::PUBLIC_KEY_SIZE;
+use bitcoin::secp256k1::PublicKey;
+use bitcoin::secp256k1::Secp256k1;
+use bitcoin::secp256k1;
+
+use bitcoin::hashes::sha256d::Hash as Sha256dHash;
+use bitcoin::hashes::Hash;
+use bitcoin::blockdata::script::Builder;
+use bitcoin::blockdata::transaction::TxOut;
+use bitcoin::blockdata::opcodes;
+use bitcoin::hash_types::BlockHash;
+
+use chain;
+use chain::Access;
+use ln::features::{ChannelFeatures, NodeFeatures};
+use ln::msgs::{DecodeError, ErrorAction, Init, LightningError, RoutingMessageHandler, NetAddress, MAX_VALUE_MSAT};
+use ln::msgs::{ChannelAnnouncement, ChannelUpdate, NodeAnnouncement, OptionalField, GossipTimestampFilter};
+use ln::msgs::{QueryChannelRange, ReplyChannelRange, QueryShortChannelIds, ReplyShortChannelIdsEnd};
+use ln::msgs;
+use util::ser::{Writeable, Readable, Writer};
+use util::logger::{Logger, Level};
+use util::events::{Event, EventHandler, MessageSendEvent, MessageSendEventsProvider};
+use util::scid_utils::{block_from_scid, scid_from_parts, MAX_SCID_BLOCK};
+
+use io;
+use prelude::*;
+use alloc::collections::{BTreeMap, btree_map::Entry as BtreeEntry};
+use core::{cmp, fmt};
+use sync::{RwLock, RwLockReadGuard};
+use core::sync::atomic::{AtomicUsize, Ordering};
+use sync::Mutex;
+use core::ops::Deref;
+use bitcoin::hashes::hex::ToHex;
+
+#[cfg(feature = "std")]
+use std::time::{SystemTime, UNIX_EPOCH};
+
+/// We remove stale channel directional info two weeks after the last update, per BOLT 7's
+/// suggestion.
+const STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS: u64 = 60 * 60 * 24 * 14;
+
+/// The maximum number of extra bytes which we do not understand in a gossip message before we will
+/// refuse to relay the message.
+const MAX_EXCESS_BYTES_FOR_RELAY: usize = 1024;
+
+/// Maximum number of short_channel_ids that will be encoded in one gossip reply message.
+/// This value ensures a reply fits within the 65k payload limit and is consistent with other implementations.
+const MAX_SCIDS_PER_REPLY: usize = 8000;
+
+/// Represents the compressed public key of a node
+#[derive(Clone, Copy)]
+pub struct NodeId([u8; PUBLIC_KEY_SIZE]);
+
+impl NodeId {
+       /// Create a new NodeId from a public key
+       pub fn from_pubkey(pubkey: &PublicKey) -> Self {
+               NodeId(pubkey.serialize())
+       }
+
+       /// Get the public key slice from this NodeId
+       pub fn as_slice(&self) -> &[u8] {
+               &self.0
+       }
+}
+
+impl fmt::Debug for NodeId {
+       fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+               write!(f, "NodeId({})", log_bytes!(self.0))
+       }
+}
+
+impl core::hash::Hash for NodeId {
+       fn hash<H: core::hash::Hasher>(&self, hasher: &mut H) {
+               self.0.hash(hasher);
+       }
+}
+
+impl Eq for NodeId {}
+
+impl PartialEq for NodeId {
+       fn eq(&self, other: &Self) -> bool {
+               self.0[..] == other.0[..]
+       }
+}
+
+impl cmp::PartialOrd for NodeId {
+       fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
+               Some(self.cmp(other))
+       }
+}
+
+impl Ord for NodeId {
+       fn cmp(&self, other: &Self) -> cmp::Ordering {
+               self.0[..].cmp(&other.0[..])
+       }
+}
+
+impl Writeable for NodeId {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+               writer.write_all(&self.0)?;
+               Ok(())
+       }
+}
+
+impl Readable for NodeId {
+       fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+               let mut buf = [0; PUBLIC_KEY_SIZE];
+               reader.read_exact(&mut buf)?;
+               Ok(Self(buf))
+       }
+}
+
+/// Represents the network as nodes and channels between them
+pub struct NetworkGraph {
+       last_rapid_gossip_sync_timestamp: Mutex<Option<u32>>,
+       genesis_hash: BlockHash,
+       // Lock order: channels -> nodes
+       channels: RwLock<BTreeMap<u64, ChannelInfo>>,
+       nodes: RwLock<BTreeMap<NodeId, NodeInfo>>,
+}
+
+impl Clone for NetworkGraph {
+       fn clone(&self) -> Self {
+               let channels = self.channels.read().unwrap();
+               let nodes = self.nodes.read().unwrap();
+               let last_rapid_gossip_sync_timestamp = self.get_last_rapid_gossip_sync_timestamp();
+               Self {
+                       genesis_hash: self.genesis_hash.clone(),
+                       channels: RwLock::new(channels.clone()),
+                       nodes: RwLock::new(nodes.clone()),
+                       last_rapid_gossip_sync_timestamp: Mutex::new(last_rapid_gossip_sync_timestamp)
+               }
+       }
+}
+
+/// A read-only view of [`NetworkGraph`].
+pub struct ReadOnlyNetworkGraph<'a> {
+       channels: RwLockReadGuard<'a, BTreeMap<u64, ChannelInfo>>,
+       nodes: RwLockReadGuard<'a, BTreeMap<NodeId, NodeInfo>>,
+}
+
+/// Update to the [`NetworkGraph`] based on payment failure information conveyed via the Onion
+/// return packet by a node along the route. See [BOLT #4] for details.
+///
+/// [BOLT #4]: https://github.com/lightning/bolts/blob/master/04-onion-routing.md
+#[derive(Clone, Debug, PartialEq)]
+pub enum NetworkUpdate {
+       /// An error indicating a `channel_update` messages should be applied via
+       /// [`NetworkGraph::update_channel`].
+       ChannelUpdateMessage {
+               /// The update to apply via [`NetworkGraph::update_channel`].
+               msg: ChannelUpdate,
+       },
+       /// An error indicating that a channel failed to route a payment, which should be applied via
+       /// [`NetworkGraph::channel_failed`].
+       ChannelFailure {
+               /// The short channel id of the closed channel.
+               short_channel_id: u64,
+               /// Whether the channel should be permanently removed or temporarily disabled until a new
+               /// `channel_update` message is received.
+               is_permanent: bool,
+       },
+       /// An error indicating that a node failed to route a payment, which should be applied via
+       /// [`NetworkGraph::node_failed`].
+       NodeFailure {
+               /// The node id of the failed node.
+               node_id: PublicKey,
+               /// Whether the node should be permanently removed from consideration or can be restored
+               /// when a new `channel_update` message is received.
+               is_permanent: bool,
+       }
+}
+
+impl_writeable_tlv_based_enum_upgradable!(NetworkUpdate,
+       (0, ChannelUpdateMessage) => {
+               (0, msg, required),
+       },
+       (2, ChannelFailure) => {
+               (0, short_channel_id, required),
+               (2, is_permanent, required),
+       },
+       (4, NodeFailure) => {
+               (0, node_id, required),
+               (2, is_permanent, required),
+       },
+);
+
+impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> EventHandler for P2PGossipSync<G, C, L>
+where C::Target: chain::Access, L::Target: Logger {
+       fn handle_event(&self, event: &Event) {
+               if let Event::PaymentPathFailed { payment_hash: _, rejected_by_dest: _, network_update, .. } = event {
+                       if let Some(network_update) = network_update {
+                               self.handle_network_update(network_update);
+                       }
+               }
+       }
+}
+
+/// Receives and validates network updates from peers,
+/// stores authentic and relevant data as a network graph.
+/// This network graph is then used for routing payments.
+/// Provides interface to help with initial routing sync by
+/// serving historical announcements.
+///
+/// Serves as an [`EventHandler`] for applying updates from [`Event::PaymentPathFailed`] to the
+/// [`NetworkGraph`].
+pub struct P2PGossipSync<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref>
+where C::Target: chain::Access, L::Target: Logger
+{
+       secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
+       network_graph: G,
+       chain_access: Option<C>,
+       full_syncs_requested: AtomicUsize,
+       pending_events: Mutex<Vec<MessageSendEvent>>,
+       logger: L,
+}
+
+impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> P2PGossipSync<G, C, L>
+where C::Target: chain::Access, L::Target: Logger
+{
+       /// Creates a new tracker of the actual state of the network of channels and nodes,
+       /// assuming an existing Network Graph.
+       /// Chain monitor is used to make sure announced channels exist on-chain,
+       /// channel data is correct, and that the announcement is signed with
+       /// channel owners' keys.
+       pub fn new(network_graph: G, chain_access: Option<C>, logger: L) -> Self {
+               P2PGossipSync {
+                       secp_ctx: Secp256k1::verification_only(),
+                       network_graph,
+                       full_syncs_requested: AtomicUsize::new(0),
+                       chain_access,
+                       pending_events: Mutex::new(vec![]),
+                       logger,
+               }
+       }
+
+       /// Adds a provider used to check new announcements. Does not affect
+       /// existing announcements unless they are updated.
+       /// Add, update or remove the provider would replace the current one.
+       pub fn add_chain_access(&mut self, chain_access: Option<C>) {
+               self.chain_access = chain_access;
+       }
+
+       /// Gets a reference to the underlying [`NetworkGraph`] which was provided in
+       /// [`P2PGossipSync::new`].
+       ///
+       /// (C-not exported) as bindings don't support a reference-to-a-reference yet
+       pub fn network_graph(&self) -> &G {
+               &self.network_graph
+       }
+
+       /// Returns true when a full routing table sync should be performed with a peer.
+       fn should_request_full_sync(&self, _node_id: &PublicKey) -> bool {
+               //TODO: Determine whether to request a full sync based on the network map.
+               const FULL_SYNCS_TO_REQUEST: usize = 5;
+               if self.full_syncs_requested.load(Ordering::Acquire) < FULL_SYNCS_TO_REQUEST {
+                       self.full_syncs_requested.fetch_add(1, Ordering::AcqRel);
+                       true
+               } else {
+                       false
+               }
+       }
+
+       /// Applies changes to the [`NetworkGraph`] from the given update.
+       fn handle_network_update(&self, update: &NetworkUpdate) {
+               match *update {
+                       NetworkUpdate::ChannelUpdateMessage { ref msg } => {
+                               let short_channel_id = msg.contents.short_channel_id;
+                               let is_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
+                               let status = if is_enabled { "enabled" } else { "disabled" };
+                               log_debug!(self.logger, "Updating channel with channel_update from a payment failure. Channel {} is {}.", short_channel_id, status);
+                               let _ = self.network_graph.update_channel(msg, &self.secp_ctx);
+                       },
+                       NetworkUpdate::ChannelFailure { short_channel_id, is_permanent } => {
+                               let action = if is_permanent { "Removing" } else { "Disabling" };
+                               log_debug!(self.logger, "{} channel graph entry for {} due to a payment failure.", action, short_channel_id);
+                               self.network_graph.channel_failed(short_channel_id, is_permanent);
+                       },
+                       NetworkUpdate::NodeFailure { ref node_id, is_permanent } => {
+                               let action = if is_permanent { "Removing" } else { "Disabling" };
+                               log_debug!(self.logger, "{} node graph entry for {} due to a payment failure.", action, node_id);
+                               self.network_graph.node_failed(node_id, is_permanent);
+                       },
+               }
+       }
+}
+
+macro_rules! secp_verify_sig {
+       ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr, $msg_type: expr ) => {
+               match $secp_ctx.verify_ecdsa($msg, $sig, $pubkey) {
+                       Ok(_) => {},
+                       Err(_) => {
+                               return Err(LightningError {
+                                       err: format!("Invalid signature on {} message", $msg_type),
+                                       action: ErrorAction::SendWarningMessage {
+                                               msg: msgs::WarningMessage {
+                                                       channel_id: [0; 32],
+                                                       data: format!("Invalid signature on {} message", $msg_type),
+                                               },
+                                               log_level: Level::Trace,
+                                       },
+                               });
+                       },
+               }
+       };
+}
+
+impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> RoutingMessageHandler for P2PGossipSync<G, C, L>
+where C::Target: chain::Access, L::Target: Logger
+{
+       fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> {
+               self.network_graph.update_node_from_announcement(msg, &self.secp_ctx)?;
+               Ok(msg.contents.excess_data.len() <=  MAX_EXCESS_BYTES_FOR_RELAY &&
+                  msg.contents.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY &&
+                  msg.contents.excess_data.len() + msg.contents.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY)
+       }
+
+       fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> {
+               self.network_graph.update_channel_from_announcement(msg, &self.chain_access, &self.secp_ctx)?;
+               log_gossip!(self.logger, "Added channel_announcement for {}{}", msg.contents.short_channel_id, if !msg.contents.excess_data.is_empty() { " with excess uninterpreted data!" } else { "" });
+               Ok(msg.contents.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY)
+       }
+
+       fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> {
+               self.network_graph.update_channel(msg, &self.secp_ctx)?;
+               Ok(msg.contents.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY)
+       }
+
+       fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(ChannelAnnouncement, Option<ChannelUpdate>, Option<ChannelUpdate>)> {
+               let mut result = Vec::with_capacity(batch_amount as usize);
+               let channels = self.network_graph.channels.read().unwrap();
+               let mut iter = channels.range(starting_point..);
+               while result.len() < batch_amount as usize {
+                       if let Some((_, ref chan)) = iter.next() {
+                               if chan.announcement_message.is_some() {
+                                       let chan_announcement = chan.announcement_message.clone().unwrap();
+                                       let mut one_to_two_announcement: Option<msgs::ChannelUpdate> = None;
+                                       let mut two_to_one_announcement: Option<msgs::ChannelUpdate> = None;
+                                       if let Some(one_to_two) = chan.one_to_two.as_ref() {
+                                               one_to_two_announcement = one_to_two.last_update_message.clone();
+                                       }
+                                       if let Some(two_to_one) = chan.two_to_one.as_ref() {
+                                               two_to_one_announcement = two_to_one.last_update_message.clone();
+                                       }
+                                       result.push((chan_announcement, one_to_two_announcement, two_to_one_announcement));
+                               } else {
+                                       // TODO: We may end up sending un-announced channel_updates if we are sending
+                                       // initial sync data while receiving announce/updates for this channel.
+                               }
+                       } else {
+                               return result;
+                       }
+               }
+               result
+       }
+
+       fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<NodeAnnouncement> {
+               let mut result = Vec::with_capacity(batch_amount as usize);
+               let nodes = self.network_graph.nodes.read().unwrap();
+               let mut iter = if let Some(pubkey) = starting_point {
+                               let mut iter = nodes.range(NodeId::from_pubkey(pubkey)..);
+                               iter.next();
+                               iter
+                       } else {
+                               nodes.range::<NodeId, _>(..)
+                       };
+               while result.len() < batch_amount as usize {
+                       if let Some((_, ref node)) = iter.next() {
+                               if let Some(node_info) = node.announcement_info.as_ref() {
+                                       if node_info.announcement_message.is_some() {
+                                               result.push(node_info.announcement_message.clone().unwrap());
+                                       }
+                               }
+                       } else {
+                               return result;
+                       }
+               }
+               result
+       }
+
+       /// Initiates a stateless sync of routing gossip information with a peer
+       /// using gossip_queries. The default strategy used by this implementation
+       /// is to sync the full block range with several peers.
+       ///
+       /// We should expect one or more reply_channel_range messages in response
+       /// to our query_channel_range. Each reply will enqueue a query_scid message
+       /// to request gossip messages for each channel. The sync is considered complete
+       /// when the final reply_scids_end message is received, though we are not
+       /// tracking this directly.
+       fn peer_connected(&self, their_node_id: &PublicKey, init_msg: &Init) {
+               // We will only perform a sync with peers that support gossip_queries.
+               if !init_msg.features.supports_gossip_queries() {
+                       return ();
+               }
+
+               // The lightning network's gossip sync system is completely broken in numerous ways.
+               //
+               // Given no broadly-available set-reconciliation protocol, the only reasonable approach is
+               // to do a full sync from the first few peers we connect to, and then receive gossip
+               // updates from all our peers normally.
+               //
+               // Originally, we could simply tell a peer to dump us the entire gossip table on startup,
+               // wasting lots of bandwidth but ensuring we have the full network graph. After the initial
+               // dump peers would always send gossip and we'd stay up-to-date with whatever our peer has
+               // seen.
+               //
+               // In order to reduce the bandwidth waste, "gossip queries" were introduced, allowing you
+               // to ask for the SCIDs of all channels in your peer's routing graph, and then only request
+               // channel data which you are missing. Except there was no way at all to identify which
+               // `channel_update`s you were missing, so you still had to request everything, just in a
+               // very complicated way with some queries instead of just getting the dump.
+               //
+               // Later, an option was added to fetch the latest timestamps of the `channel_update`s to
+               // make efficient sync possible, however it has yet to be implemented in lnd, which makes
+               // relying on it useless.
+               //
+               // After gossip queries were introduced, support for receiving a full gossip table dump on
+               // connection was removed from several nodes, making it impossible to get a full sync
+               // without using the "gossip queries" messages.
+               //
+               // Once you opt into "gossip queries" the only way to receive any gossip updates that a
+               // peer receives after you connect, you must send a `gossip_timestamp_filter` message. This
+               // message, as the name implies, tells the peer to not forward any gossip messages with a
+               // timestamp older than a given value (not the time the peer received the filter, but the
+               // timestamp in the update message, which is often hours behind when the peer received the
+               // message).
+               //
+               // Obnoxiously, `gossip_timestamp_filter` isn't *just* a filter, but its also a request for
+               // your peer to send you the full routing graph (subject to the filter). Thus, in order to
+               // tell a peer to send you any updates as it sees them, you have to also ask for the full
+               // routing graph to be synced. If you set a timestamp filter near the current time, peers
+               // will simply not forward any new updates they see to you which were generated some time
+               // ago (which is not uncommon). If you instead set a timestamp filter near 0 (or two weeks
+               // ago), you will always get the full routing graph from all your peers.
+               //
+               // Most lightning nodes today opt to simply turn off receiving gossip data which only
+               // propagated some time after it was generated, and, worse, often disable gossiping with
+               // several peers after their first connection. The second behavior can cause gossip to not
+               // propagate fully if there are cuts in the gossiping subgraph.
+               //
+               // In an attempt to cut a middle ground between always fetching the full graph from all of
+               // our peers and never receiving gossip from peers at all, we send all of our peers a
+               // `gossip_timestamp_filter`, with the filter time set either two weeks ago or an hour ago.
+               //
+               // For no-std builds, we bury our head in the sand and do a full sync on each connection.
+               let should_request_full_sync = self.should_request_full_sync(&their_node_id);
+               #[allow(unused_mut, unused_assignments)]
+               let mut gossip_start_time = 0;
+               #[cfg(feature = "std")]
+               {
+                       gossip_start_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+                       if should_request_full_sync {
+                               gossip_start_time -= 60 * 60 * 24 * 7 * 2; // 2 weeks ago
+                       } else {
+                               gossip_start_time -= 60 * 60; // an hour ago
+                       }
+               }
+
+               let mut pending_events = self.pending_events.lock().unwrap();
+               pending_events.push(MessageSendEvent::SendGossipTimestampFilter {
+                       node_id: their_node_id.clone(),
+                       msg: GossipTimestampFilter {
+                               chain_hash: self.network_graph.genesis_hash,
+                               first_timestamp: gossip_start_time as u32, // 2106 issue!
+                               timestamp_range: u32::max_value(),
+                       },
+               });
+       }
+
+       fn handle_reply_channel_range(&self, _their_node_id: &PublicKey, _msg: ReplyChannelRange) -> Result<(), LightningError> {
+               // We don't make queries, so should never receive replies. If, in the future, the set
+               // reconciliation extensions to gossip queries become broadly supported, we should revert
+               // this code to its state pre-0.0.106.
+               Ok(())
+       }
+
+       fn handle_reply_short_channel_ids_end(&self, _their_node_id: &PublicKey, _msg: ReplyShortChannelIdsEnd) -> Result<(), LightningError> {
+               // We don't make queries, so should never receive replies. If, in the future, the set
+               // reconciliation extensions to gossip queries become broadly supported, we should revert
+               // this code to its state pre-0.0.106.
+               Ok(())
+       }
+
+       /// Processes a query from a peer by finding announced/public channels whose funding UTXOs
+       /// are in the specified block range. Due to message size limits, large range
+       /// queries may result in several reply messages. This implementation enqueues
+       /// all reply messages into pending events. Each message will allocate just under 65KiB. A full
+       /// sync of the public routing table with 128k channels will generated 16 messages and allocate ~1MB.
+       /// Logic can be changed to reduce allocation if/when a full sync of the routing table impacts
+       /// memory constrained systems.
+       fn handle_query_channel_range(&self, their_node_id: &PublicKey, msg: QueryChannelRange) -> Result<(), LightningError> {
+               log_debug!(self.logger, "Handling query_channel_range peer={}, first_blocknum={}, number_of_blocks={}", log_pubkey!(their_node_id), msg.first_blocknum, msg.number_of_blocks);
+
+               let inclusive_start_scid = scid_from_parts(msg.first_blocknum as u64, 0, 0);
+
+               // We might receive valid queries with end_blocknum that would overflow SCID conversion.
+               // If so, we manually cap the ending block to avoid this overflow.
+               let exclusive_end_scid = scid_from_parts(cmp::min(msg.end_blocknum() as u64, MAX_SCID_BLOCK), 0, 0);
+
+               // Per spec, we must reply to a query. Send an empty message when things are invalid.
+               if msg.chain_hash != self.network_graph.genesis_hash || inclusive_start_scid.is_err() || exclusive_end_scid.is_err() || msg.number_of_blocks == 0 {
+                       let mut pending_events = self.pending_events.lock().unwrap();
+                       pending_events.push(MessageSendEvent::SendReplyChannelRange {
+                               node_id: their_node_id.clone(),
+                               msg: ReplyChannelRange {
+                                       chain_hash: msg.chain_hash.clone(),
+                                       first_blocknum: msg.first_blocknum,
+                                       number_of_blocks: msg.number_of_blocks,
+                                       sync_complete: true,
+                                       short_channel_ids: vec![],
+                               }
+                       });
+                       return Err(LightningError {
+                               err: String::from("query_channel_range could not be processed"),
+                               action: ErrorAction::IgnoreError,
+                       });
+               }
+
+               // Creates channel batches. We are not checking if the channel is routable
+               // (has at least one update). A peer may still want to know the channel
+               // exists even if its not yet routable.
+               let mut batches: Vec<Vec<u64>> = vec![Vec::with_capacity(MAX_SCIDS_PER_REPLY)];
+               let channels = self.network_graph.channels.read().unwrap();
+               for (_, ref chan) in channels.range(inclusive_start_scid.unwrap()..exclusive_end_scid.unwrap()) {
+                       if let Some(chan_announcement) = &chan.announcement_message {
+                               // Construct a new batch if last one is full
+                               if batches.last().unwrap().len() == batches.last().unwrap().capacity() {
+                                       batches.push(Vec::with_capacity(MAX_SCIDS_PER_REPLY));
+                               }
+
+                               let batch = batches.last_mut().unwrap();
+                               batch.push(chan_announcement.contents.short_channel_id);
+                       }
+               }
+               drop(channels);
+
+               let mut pending_events = self.pending_events.lock().unwrap();
+               let batch_count = batches.len();
+               let mut prev_batch_endblock = msg.first_blocknum;
+               for (batch_index, batch) in batches.into_iter().enumerate() {
+                       // Per spec, the initial `first_blocknum` needs to be <= the query's `first_blocknum`
+                       // and subsequent `first_blocknum`s must be >= the prior reply's `first_blocknum`.
+                       //
+                       // Additionally, c-lightning versions < 0.10 require that the `first_blocknum` of each
+                       // reply is >= the previous reply's `first_blocknum` and either exactly the previous
+                       // reply's `first_blocknum + number_of_blocks` or exactly one greater. This is a
+                       // significant diversion from the requirements set by the spec, and, in case of blocks
+                       // with no channel opens (e.g. empty blocks), requires that we use the previous value
+                       // and *not* derive the first_blocknum from the actual first block of the reply.
+                       let first_blocknum = prev_batch_endblock;
+
+                       // Each message carries the number of blocks (from the `first_blocknum`) its contents
+                       // fit in. Though there is no requirement that we use exactly the number of blocks its
+                       // contents are from, except for the bogus requirements c-lightning enforces, above.
+                       //
+                       // Per spec, the last end block (ie `first_blocknum + number_of_blocks`) needs to be
+                       // >= the query's end block. Thus, for the last reply, we calculate the difference
+                       // between the query's end block and the start of the reply.
+                       //
+                       // Overflow safe since end_blocknum=msg.first_block_num+msg.number_of_blocks and
+                       // first_blocknum will be either msg.first_blocknum or a higher block height.
+                       let (sync_complete, number_of_blocks) = if batch_index == batch_count-1 {
+                               (true, msg.end_blocknum() - first_blocknum)
+                       }
+                       // Prior replies should use the number of blocks that fit into the reply. Overflow
+                       // safe since first_blocknum is always <= last SCID's block.
+                       else {
+                               (false, block_from_scid(batch.last().unwrap()) - first_blocknum)
+                       };
+
+                       prev_batch_endblock = first_blocknum + number_of_blocks;
+
+                       pending_events.push(MessageSendEvent::SendReplyChannelRange {
+                               node_id: their_node_id.clone(),
+                               msg: ReplyChannelRange {
+                                       chain_hash: msg.chain_hash.clone(),
+                                       first_blocknum,
+                                       number_of_blocks,
+                                       sync_complete,
+                                       short_channel_ids: batch,
+                               }
+                       });
+               }
+
+               Ok(())
+       }
+
+       fn handle_query_short_channel_ids(&self, _their_node_id: &PublicKey, _msg: QueryShortChannelIds) -> Result<(), LightningError> {
+               // TODO
+               Err(LightningError {
+                       err: String::from("Not implemented"),
+                       action: ErrorAction::IgnoreError,
+               })
+       }
+}
+
+impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> MessageSendEventsProvider for P2PGossipSync<G, C, L>
+where
+       C::Target: chain::Access,
+       L::Target: Logger,
+{
+       fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
+               let mut ret = Vec::new();
+               let mut pending_events = self.pending_events.lock().unwrap();
+               core::mem::swap(&mut ret, &mut pending_events);
+               ret
+       }
+}
+
+#[derive(Clone, Debug, PartialEq)]
+/// Details about one direction of a channel as received within a [`ChannelUpdate`].
+pub struct ChannelUpdateInfo {
+       /// When the last update to the channel direction was issued.
+       /// Value is opaque, as set in the announcement.
+       pub last_update: u32,
+       /// Whether the channel can be currently used for payments (in this one direction).
+       pub enabled: bool,
+       /// The difference in CLTV values that you must have when routing through this channel.
+       pub cltv_expiry_delta: u16,
+       /// The minimum value, which must be relayed to the next hop via the channel
+       pub htlc_minimum_msat: u64,
+       /// The maximum value which may be relayed to the next hop via the channel.
+       pub htlc_maximum_msat: Option<u64>,
+       /// Fees charged when the channel is used for routing
+       pub fees: RoutingFees,
+       /// Most recent update for the channel received from the network
+       /// Mostly redundant with the data we store in fields explicitly.
+       /// Everything else is useful only for sending out for initial routing sync.
+       /// Not stored if contains excess data to prevent DoS.
+       pub last_update_message: Option<ChannelUpdate>,
+}
+
+impl fmt::Display for ChannelUpdateInfo {
+       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+               write!(f, "last_update {}, enabled {}, cltv_expiry_delta {}, htlc_minimum_msat {}, fees {:?}", self.last_update, self.enabled, self.cltv_expiry_delta, self.htlc_minimum_msat, self.fees)?;
+               Ok(())
+       }
+}
+
+impl_writeable_tlv_based!(ChannelUpdateInfo, {
+       (0, last_update, required),
+       (2, enabled, required),
+       (4, cltv_expiry_delta, required),
+       (6, htlc_minimum_msat, required),
+       (8, htlc_maximum_msat, required),
+       (10, fees, required),
+       (12, last_update_message, required),
+});
+
+#[derive(Clone, Debug, PartialEq)]
+/// Details about a channel (both directions).
+/// Received within a channel announcement.
+pub struct ChannelInfo {
+       /// Protocol features of a channel communicated during its announcement
+       pub features: ChannelFeatures,
+       /// Source node of the first direction of a channel
+       pub node_one: NodeId,
+       /// Details about the first direction of a channel
+       pub one_to_two: Option<ChannelUpdateInfo>,
+       /// Source node of the second direction of a channel
+       pub node_two: NodeId,
+       /// Details about the second direction of a channel
+       pub two_to_one: Option<ChannelUpdateInfo>,
+       /// The channel capacity as seen on-chain, if chain lookup is available.
+       pub capacity_sats: Option<u64>,
+       /// An initial announcement of the channel
+       /// Mostly redundant with the data we store in fields explicitly.
+       /// Everything else is useful only for sending out for initial routing sync.
+       /// Not stored if contains excess data to prevent DoS.
+       pub announcement_message: Option<ChannelAnnouncement>,
+       /// The timestamp when we received the announcement, if we are running with feature = "std"
+       /// (which we can probably assume we are - no-std environments probably won't have a full
+       /// network graph in memory!).
+       announcement_received_time: u64,
+}
+
+impl ChannelInfo {
+       /// Returns a [`DirectedChannelInfo`] for the channel directed to the given `target` from a
+       /// returned `source`, or `None` if `target` is not one of the channel's counterparties.
+       pub fn as_directed_to(&self, target: &NodeId) -> Option<(DirectedChannelInfo, &NodeId)> {
+               let (direction, source) = {
+                       if target == &self.node_one {
+                               (self.two_to_one.as_ref(), &self.node_two)
+                       } else if target == &self.node_two {
+                               (self.one_to_two.as_ref(), &self.node_one)
+                       } else {
+                               return None;
+                       }
+               };
+               Some((DirectedChannelInfo::new(self, direction), source))
+       }
+
+       /// Returns a [`DirectedChannelInfo`] for the channel directed from the given `source` to a
+       /// returned `target`, or `None` if `source` is not one of the channel's counterparties.
+       pub fn as_directed_from(&self, source: &NodeId) -> Option<(DirectedChannelInfo, &NodeId)> {
+               let (direction, target) = {
+                       if source == &self.node_one {
+                               (self.one_to_two.as_ref(), &self.node_two)
+                       } else if source == &self.node_two {
+                               (self.two_to_one.as_ref(), &self.node_one)
+                       } else {
+                               return None;
+                       }
+               };
+               Some((DirectedChannelInfo::new(self, direction), target))
+       }
+
+       /// Returns a [`ChannelUpdateInfo`] based on the direction implied by the channel_flag.
+       pub fn get_directional_info(&self, channel_flags: u8) -> Option<&ChannelUpdateInfo> {
+               let direction = channel_flags & 1u8;
+               if direction == 0 {
+                       self.one_to_two.as_ref()
+               } else {
+                       self.two_to_one.as_ref()
+               }
+       }
+}
+
+impl fmt::Display for ChannelInfo {
+       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+               write!(f, "features: {}, node_one: {}, one_to_two: {:?}, node_two: {}, two_to_one: {:?}",
+                  log_bytes!(self.features.encode()), log_bytes!(self.node_one.as_slice()), self.one_to_two, log_bytes!(self.node_two.as_slice()), self.two_to_one)?;
+               Ok(())
+       }
+}
+
+impl_writeable_tlv_based!(ChannelInfo, {
+       (0, features, required),
+       (1, announcement_received_time, (default_value, 0)),
+       (2, node_one, required),
+       (4, one_to_two, required),
+       (6, node_two, required),
+       (8, two_to_one, required),
+       (10, capacity_sats, required),
+       (12, announcement_message, required),
+});
+
+/// A wrapper around [`ChannelInfo`] representing information about the channel as directed from a
+/// source node to a target node.
+#[derive(Clone)]
+pub struct DirectedChannelInfo<'a> {
+       channel: &'a ChannelInfo,
+       direction: Option<&'a ChannelUpdateInfo>,
+       htlc_maximum_msat: u64,
+       effective_capacity: EffectiveCapacity,
+}
+
+impl<'a> DirectedChannelInfo<'a> {
+       #[inline]
+       fn new(channel: &'a ChannelInfo, direction: Option<&'a ChannelUpdateInfo>) -> Self {
+               let htlc_maximum_msat = direction.and_then(|direction| direction.htlc_maximum_msat);
+               let capacity_msat = channel.capacity_sats.map(|capacity_sats| capacity_sats * 1000);
+
+               let (htlc_maximum_msat, effective_capacity) = match (htlc_maximum_msat, capacity_msat) {
+                       (Some(amount_msat), Some(capacity_msat)) => {
+                               let htlc_maximum_msat = cmp::min(amount_msat, capacity_msat);
+                               (htlc_maximum_msat, EffectiveCapacity::Total { capacity_msat })
+                       },
+                       (Some(amount_msat), None) => {
+                               (amount_msat, EffectiveCapacity::MaximumHTLC { amount_msat })
+                       },
+                       (None, Some(capacity_msat)) => {
+                               (capacity_msat, EffectiveCapacity::Total { capacity_msat })
+                       },
+                       (None, None) => (EffectiveCapacity::Unknown.as_msat(), EffectiveCapacity::Unknown),
+               };
+
+               Self {
+                       channel, direction, htlc_maximum_msat, effective_capacity
+               }
+       }
+
+       /// Returns information for the channel.
+       pub fn channel(&self) -> &'a ChannelInfo { self.channel }
+
+       /// Returns information for the direction.
+       pub fn direction(&self) -> Option<&'a ChannelUpdateInfo> { self.direction }
+
+       /// Returns the maximum HTLC amount allowed over the channel in the direction.
+       pub fn htlc_maximum_msat(&self) -> u64 {
+               self.htlc_maximum_msat
+       }
+
+       /// Returns the [`EffectiveCapacity`] of the channel in the direction.
+       ///
+       /// This is either the total capacity from the funding transaction, if known, or the
+       /// `htlc_maximum_msat` for the direction as advertised by the gossip network, if known,
+       /// otherwise.
+       pub fn effective_capacity(&self) -> EffectiveCapacity {
+               self.effective_capacity
+       }
+
+       /// Returns `Some` if [`ChannelUpdateInfo`] is available in the direction.
+       pub(super) fn with_update(self) -> Option<DirectedChannelInfoWithUpdate<'a>> {
+               match self.direction {
+                       Some(_) => Some(DirectedChannelInfoWithUpdate { inner: self }),
+                       None => None,
+               }
+       }
+}
+
+impl<'a> fmt::Debug for DirectedChannelInfo<'a> {
+       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+               f.debug_struct("DirectedChannelInfo")
+                       .field("channel", &self.channel)
+                       .finish()
+       }
+}
+
+/// A [`DirectedChannelInfo`] with [`ChannelUpdateInfo`] available in its direction.
+#[derive(Clone)]
+pub(super) struct DirectedChannelInfoWithUpdate<'a> {
+       inner: DirectedChannelInfo<'a>,
+}
+
+impl<'a> DirectedChannelInfoWithUpdate<'a> {
+       /// Returns information for the channel.
+       #[inline]
+       pub(super) fn channel(&self) -> &'a ChannelInfo { &self.inner.channel }
+
+       /// Returns information for the direction.
+       #[inline]
+       pub(super) fn direction(&self) -> &'a ChannelUpdateInfo { self.inner.direction.unwrap() }
+
+       /// Returns the [`EffectiveCapacity`] of the channel in the direction.
+       #[inline]
+       pub(super) fn effective_capacity(&self) -> EffectiveCapacity { self.inner.effective_capacity() }
+
+       /// Returns the maximum HTLC amount allowed over the channel in the direction.
+       #[inline]
+       pub(super) fn htlc_maximum_msat(&self) -> u64 { self.inner.htlc_maximum_msat() }
+}
+
+impl<'a> fmt::Debug for DirectedChannelInfoWithUpdate<'a> {
+       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+               self.inner.fmt(f)
+       }
+}
+
+/// The effective capacity of a channel for routing purposes.
+///
+/// While this may be smaller than the actual channel capacity, amounts greater than
+/// [`Self::as_msat`] should not be routed through the channel.
+#[derive(Clone, Copy)]
+pub enum EffectiveCapacity {
+       /// The available liquidity in the channel known from being a channel counterparty, and thus a
+       /// direct hop.
+       ExactLiquidity {
+               /// Either the inbound or outbound liquidity depending on the direction, denominated in
+               /// millisatoshi.
+               liquidity_msat: u64,
+       },
+       /// The maximum HTLC amount in one direction as advertised on the gossip network.
+       MaximumHTLC {
+               /// The maximum HTLC amount denominated in millisatoshi.
+               amount_msat: u64,
+       },
+       /// The total capacity of the channel as determined by the funding transaction.
+       Total {
+               /// The funding amount denominated in millisatoshi.
+               capacity_msat: u64,
+       },
+       /// A capacity sufficient to route any payment, typically used for private channels provided by
+       /// an invoice.
+       Infinite,
+       /// A capacity that is unknown possibly because either the chain state is unavailable to know
+       /// the total capacity or the `htlc_maximum_msat` was not advertised on the gossip network.
+       Unknown,
+}
+
+/// The presumed channel capacity denominated in millisatoshi for [`EffectiveCapacity::Unknown`] to
+/// use when making routing decisions.
+pub const UNKNOWN_CHANNEL_CAPACITY_MSAT: u64 = 250_000 * 1000;
+
+impl EffectiveCapacity {
+       /// Returns the effective capacity denominated in millisatoshi.
+       pub fn as_msat(&self) -> u64 {
+               match self {
+                       EffectiveCapacity::ExactLiquidity { liquidity_msat } => *liquidity_msat,
+                       EffectiveCapacity::MaximumHTLC { amount_msat } => *amount_msat,
+                       EffectiveCapacity::Total { capacity_msat } => *capacity_msat,
+                       EffectiveCapacity::Infinite => u64::max_value(),
+                       EffectiveCapacity::Unknown => UNKNOWN_CHANNEL_CAPACITY_MSAT,
+               }
+       }
+}
+
+/// Fees for routing via a given channel or a node
+#[derive(Eq, PartialEq, Copy, Clone, Debug, Hash)]
+pub struct RoutingFees {
+       /// Flat routing fee in satoshis
+       pub base_msat: u32,
+       /// Liquidity-based routing fee in millionths of a routed amount.
+       /// In other words, 10000 is 1%.
+       pub proportional_millionths: u32,
+}
+
+impl_writeable_tlv_based!(RoutingFees, {
+       (0, base_msat, required),
+       (2, proportional_millionths, required)
+});
+
+#[derive(Clone, Debug, PartialEq)]
+/// Information received in the latest node_announcement from this node.
+pub struct NodeAnnouncementInfo {
+       /// Protocol features the node announced support for
+       pub features: NodeFeatures,
+       /// When the last known update to the node state was issued.
+       /// Value is opaque, as set in the announcement.
+       pub last_update: u32,
+       /// Color assigned to the node
+       pub rgb: [u8; 3],
+       /// Moniker assigned to the node.
+       /// May be invalid or malicious (eg control chars),
+       /// should not be exposed to the user.
+       pub alias: [u8; 32],
+       /// Internet-level addresses via which one can connect to the node
+       pub addresses: Vec<NetAddress>,
+       /// An initial announcement of the node
+       /// Mostly redundant with the data we store in fields explicitly.
+       /// Everything else is useful only for sending out for initial routing sync.
+       /// Not stored if contains excess data to prevent DoS.
+       pub announcement_message: Option<NodeAnnouncement>
+}
+
+impl_writeable_tlv_based!(NodeAnnouncementInfo, {
+       (0, features, required),
+       (2, last_update, required),
+       (4, rgb, required),
+       (6, alias, required),
+       (8, announcement_message, option),
+       (10, addresses, vec_type),
+});
+
+#[derive(Clone, Debug, PartialEq)]
+/// Details about a node in the network, known from the network announcement.
+pub struct NodeInfo {
+       /// All valid channels a node has announced
+       pub channels: Vec<u64>,
+       /// Lowest fees enabling routing via any of the enabled, known channels to a node.
+       /// The two fields (flat and proportional fee) are independent,
+       /// meaning they don't have to refer to the same channel.
+       pub lowest_inbound_channel_fees: Option<RoutingFees>,
+       /// More information about a node from node_announcement.
+       /// Optional because we store a Node entry after learning about it from
+       /// a channel announcement, but before receiving a node announcement.
+       pub announcement_info: Option<NodeAnnouncementInfo>
+}
+
+impl fmt::Display for NodeInfo {
+       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+               write!(f, "lowest_inbound_channel_fees: {:?}, channels: {:?}, announcement_info: {:?}",
+                  self.lowest_inbound_channel_fees, &self.channels[..], self.announcement_info)?;
+               Ok(())
+       }
+}
+
+impl_writeable_tlv_based!(NodeInfo, {
+       (0, lowest_inbound_channel_fees, option),
+       (2, announcement_info, option),
+       (4, channels, vec_type),
+});
+
+const SERIALIZATION_VERSION: u8 = 1;
+const MIN_SERIALIZATION_VERSION: u8 = 1;
+
+impl Writeable for NetworkGraph {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+               write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
+
+               self.genesis_hash.write(writer)?;
+               let channels = self.channels.read().unwrap();
+               (channels.len() as u64).write(writer)?;
+               for (ref chan_id, ref chan_info) in channels.iter() {
+                       (*chan_id).write(writer)?;
+                       chan_info.write(writer)?;
+               }
+               let nodes = self.nodes.read().unwrap();
+               (nodes.len() as u64).write(writer)?;
+               for (ref node_id, ref node_info) in nodes.iter() {
+                       node_id.write(writer)?;
+                       node_info.write(writer)?;
+               }
+
+               let last_rapid_gossip_sync_timestamp = self.get_last_rapid_gossip_sync_timestamp();
+               write_tlv_fields!(writer, {
+                       (1, last_rapid_gossip_sync_timestamp, option),
+               });
+               Ok(())
+       }
+}
+
+impl Readable for NetworkGraph {
+       fn read<R: io::Read>(reader: &mut R) -> Result<NetworkGraph, DecodeError> {
+               let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
+
+               let genesis_hash: BlockHash = Readable::read(reader)?;
+               let channels_count: u64 = Readable::read(reader)?;
+               let mut channels = BTreeMap::new();
+               for _ in 0..channels_count {
+                       let chan_id: u64 = Readable::read(reader)?;
+                       let chan_info = Readable::read(reader)?;
+                       channels.insert(chan_id, chan_info);
+               }
+               let nodes_count: u64 = Readable::read(reader)?;
+               let mut nodes = BTreeMap::new();
+               for _ in 0..nodes_count {
+                       let node_id = Readable::read(reader)?;
+                       let node_info = Readable::read(reader)?;
+                       nodes.insert(node_id, node_info);
+               }
+
+               let mut last_rapid_gossip_sync_timestamp: Option<u32> = None;
+               read_tlv_fields!(reader, {
+                       (1, last_rapid_gossip_sync_timestamp, option),
+               });
+
+               Ok(NetworkGraph {
+                       genesis_hash,
+                       channels: RwLock::new(channels),
+                       nodes: RwLock::new(nodes),
+                       last_rapid_gossip_sync_timestamp: Mutex::new(last_rapid_gossip_sync_timestamp),
+               })
+       }
+}
+
+impl fmt::Display for NetworkGraph {
+       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+               writeln!(f, "Network map\n[Channels]")?;
+               for (key, val) in self.channels.read().unwrap().iter() {
+                       writeln!(f, " {}: {}", key, val)?;
+               }
+               writeln!(f, "[Nodes]")?;
+               for (&node_id, val) in self.nodes.read().unwrap().iter() {
+                       writeln!(f, " {}: {}", log_bytes!(node_id.as_slice()), val)?;
+               }
+               Ok(())
+       }
+}
+
+impl PartialEq for NetworkGraph {
+       fn eq(&self, other: &Self) -> bool {
+               self.genesis_hash == other.genesis_hash &&
+                       *self.channels.read().unwrap() == *other.channels.read().unwrap() &&
+                       *self.nodes.read().unwrap() == *other.nodes.read().unwrap()
+       }
+}
+
+impl NetworkGraph {
+       /// Creates a new, empty, network graph.
+       pub fn new(genesis_hash: BlockHash) -> NetworkGraph {
+               Self {
+                       genesis_hash,
+                       channels: RwLock::new(BTreeMap::new()),
+                       nodes: RwLock::new(BTreeMap::new()),
+                       last_rapid_gossip_sync_timestamp: Mutex::new(None),
+               }
+       }
+
+       /// Returns a read-only view of the network graph.
+       pub fn read_only(&'_ self) -> ReadOnlyNetworkGraph<'_> {
+               let channels = self.channels.read().unwrap();
+               let nodes = self.nodes.read().unwrap();
+               ReadOnlyNetworkGraph {
+                       channels,
+                       nodes,
+               }
+       }
+
+       /// The unix timestamp provided by the most recent rapid gossip sync.
+       /// It will be set by the rapid sync process after every sync completion.
+       pub fn get_last_rapid_gossip_sync_timestamp(&self) -> Option<u32> {
+               self.last_rapid_gossip_sync_timestamp.lock().unwrap().clone()
+       }
+
+       /// Update the unix timestamp provided by the most recent rapid gossip sync.
+       /// This should be done automatically by the rapid sync process after every sync completion.
+       pub fn set_last_rapid_gossip_sync_timestamp(&self, last_rapid_gossip_sync_timestamp: u32) {
+               self.last_rapid_gossip_sync_timestamp.lock().unwrap().replace(last_rapid_gossip_sync_timestamp);
+       }
+
+       /// Clears the `NodeAnnouncementInfo` field for all nodes in the `NetworkGraph` for testing
+       /// purposes.
+       #[cfg(test)]
+       pub fn clear_nodes_announcement_info(&self) {
+               for node in self.nodes.write().unwrap().iter_mut() {
+                       node.1.announcement_info = None;
+               }
+       }
+
+       /// For an already known node (from channel announcements), update its stored properties from a
+       /// given node announcement.
+       ///
+       /// You probably don't want to call this directly, instead relying on a P2PGossipSync's
+       /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
+       /// routing messages from a source using a protocol other than the lightning P2P protocol.
+       pub fn update_node_from_announcement<T: secp256k1::Verification>(&self, msg: &msgs::NodeAnnouncement, secp_ctx: &Secp256k1<T>) -> Result<(), LightningError> {
+               let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
+               secp_verify_sig!(secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id, "node_announcement");
+               self.update_node_from_announcement_intern(&msg.contents, Some(&msg))
+       }
+
+       /// For an already known node (from channel announcements), update its stored properties from a
+       /// given node announcement without verifying the associated signatures. Because we aren't
+       /// given the associated signatures here we cannot relay the node announcement to any of our
+       /// peers.
+       pub fn update_node_from_unsigned_announcement(&self, msg: &msgs::UnsignedNodeAnnouncement) -> Result<(), LightningError> {
+               self.update_node_from_announcement_intern(msg, None)
+       }
+
+       fn update_node_from_announcement_intern(&self, msg: &msgs::UnsignedNodeAnnouncement, full_msg: Option<&msgs::NodeAnnouncement>) -> Result<(), LightningError> {
+               match self.nodes.write().unwrap().get_mut(&NodeId::from_pubkey(&msg.node_id)) {
+                       None => Err(LightningError{err: "No existing channels for node_announcement".to_owned(), action: ErrorAction::IgnoreError}),
+                       Some(node) => {
+                               if let Some(node_info) = node.announcement_info.as_ref() {
+                                       // The timestamp field is somewhat of a misnomer - the BOLTs use it to order
+                                       // updates to ensure you always have the latest one, only vaguely suggesting
+                                       // that it be at least the current time.
+                                       if node_info.last_update  > msg.timestamp {
+                                               return Err(LightningError{err: "Update older than last processed update".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                                       } else if node_info.last_update  == msg.timestamp {
+                                               return Err(LightningError{err: "Update had the same timestamp as last processed update".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
+                                       }
+                               }
+
+                               let should_relay =
+                                       msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY &&
+                                       msg.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY &&
+                                       msg.excess_data.len() + msg.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY;
+                               node.announcement_info = Some(NodeAnnouncementInfo {
+                                       features: msg.features.clone(),
+                                       last_update: msg.timestamp,
+                                       rgb: msg.rgb,
+                                       alias: msg.alias,
+                                       addresses: msg.addresses.clone(),
+                                       announcement_message: if should_relay { full_msg.cloned() } else { None },
+                               });
+
+                               Ok(())
+                       }
+               }
+       }
+
+       /// Store or update channel info from a channel announcement.
+       ///
+       /// You probably don't want to call this directly, instead relying on a P2PGossipSync's
+       /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
+       /// routing messages from a source using a protocol other than the lightning P2P protocol.
+       ///
+       /// If a `chain::Access` object is provided via `chain_access`, it will be called to verify
+       /// the corresponding UTXO exists on chain and is correctly-formatted.
+       pub fn update_channel_from_announcement<T: secp256k1::Verification, C: Deref>(
+               &self, msg: &msgs::ChannelAnnouncement, chain_access: &Option<C>, secp_ctx: &Secp256k1<T>
+       ) -> Result<(), LightningError>
+       where
+               C::Target: chain::Access,
+       {
+               let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
+               secp_verify_sig!(secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1, "channel_announcement");
+               secp_verify_sig!(secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2, "channel_announcement");
+               secp_verify_sig!(secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1, "channel_announcement");
+               secp_verify_sig!(secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2, "channel_announcement");
+               self.update_channel_from_unsigned_announcement_intern(&msg.contents, Some(msg), chain_access)
+       }
+
+       /// Store or update channel info from a channel announcement without verifying the associated
+       /// signatures. Because we aren't given the associated signatures here we cannot relay the
+       /// channel announcement to any of our peers.
+       ///
+       /// If a `chain::Access` object is provided via `chain_access`, it will be called to verify
+       /// the corresponding UTXO exists on chain and is correctly-formatted.
+       pub fn update_channel_from_unsigned_announcement<C: Deref>(
+               &self, msg: &msgs::UnsignedChannelAnnouncement, chain_access: &Option<C>
+       ) -> Result<(), LightningError>
+       where
+               C::Target: chain::Access,
+       {
+               self.update_channel_from_unsigned_announcement_intern(msg, None, chain_access)
+       }
+
+       /// Update channel from partial announcement data received via rapid gossip sync
+       ///
+       /// `timestamp: u64`: Timestamp emulating the backdated original announcement receipt (by the
+       /// rapid gossip sync server)
+       ///
+       /// All other parameters as used in [`msgs::UnsignedChannelAnnouncement`] fields.
+       pub fn add_channel_from_partial_announcement(&self, short_channel_id: u64, timestamp: u64, features: ChannelFeatures, node_id_1: PublicKey, node_id_2: PublicKey) -> Result<(), LightningError> {
+               if node_id_1 == node_id_2 {
+                       return Err(LightningError{err: "Channel announcement node had a channel with itself".to_owned(), action: ErrorAction::IgnoreError});
+               };
+
+               let node_1 = NodeId::from_pubkey(&node_id_1);
+               let node_2 = NodeId::from_pubkey(&node_id_2);
+               let channel_info = ChannelInfo {
+                       features,
+                       node_one: node_1.clone(),
+                       one_to_two: None,
+                       node_two: node_2.clone(),
+                       two_to_one: None,
+                       capacity_sats: None,
+                       announcement_message: None,
+                       announcement_received_time: timestamp,
+               };
+
+               self.add_channel_between_nodes(short_channel_id, channel_info, None)
+       }
+
+       fn add_channel_between_nodes(&self, short_channel_id: u64, channel_info: ChannelInfo, utxo_value: Option<u64>) -> Result<(), LightningError> {
+               let mut channels = self.channels.write().unwrap();
+               let mut nodes = self.nodes.write().unwrap();
+
+               let node_id_a = channel_info.node_one.clone();
+               let node_id_b = channel_info.node_two.clone();
+
+               match channels.entry(short_channel_id) {
+                       BtreeEntry::Occupied(mut entry) => {
+                               //TODO: because asking the blockchain if short_channel_id is valid is only optional
+                               //in the blockchain API, we need to handle it smartly here, though it's unclear
+                               //exactly how...
+                               if utxo_value.is_some() {
+                                       // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
+                                       // only sometimes returns results. In any case remove the previous entry. Note
+                                       // that the spec expects us to "blacklist" the node_ids involved, but we can't
+                                       // do that because
+                                       // a) we don't *require* a UTXO provider that always returns results.
+                                       // b) we don't track UTXOs of channels we know about and remove them if they
+                                       //    get reorg'd out.
+                                       // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
+                                       Self::remove_channel_in_nodes(&mut nodes, &entry.get(), short_channel_id);
+                                       *entry.get_mut() = channel_info;
+                               } else {
+                                       return Err(LightningError{err: "Already have knowledge of channel".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
+                               }
+                       },
+                       BtreeEntry::Vacant(entry) => {
+                               entry.insert(channel_info);
+                       }
+               };
+
+               for current_node_id in [node_id_a, node_id_b].iter() {
+                       match nodes.entry(current_node_id.clone()) {
+                               BtreeEntry::Occupied(node_entry) => {
+                                       node_entry.into_mut().channels.push(short_channel_id);
+                               },
+                               BtreeEntry::Vacant(node_entry) => {
+                                       node_entry.insert(NodeInfo {
+                                               channels: vec!(short_channel_id),
+                                               lowest_inbound_channel_fees: None,
+                                               announcement_info: None,
+                                       });
+                               }
+                       };
+               };
+
+               Ok(())
+       }
+
+       fn update_channel_from_unsigned_announcement_intern<C: Deref>(
+               &self, msg: &msgs::UnsignedChannelAnnouncement, full_msg: Option<&msgs::ChannelAnnouncement>, chain_access: &Option<C>
+       ) -> Result<(), LightningError>
+       where
+               C::Target: chain::Access,
+       {
+               if msg.node_id_1 == msg.node_id_2 || msg.bitcoin_key_1 == msg.bitcoin_key_2 {
+                       return Err(LightningError{err: "Channel announcement node had a channel with itself".to_owned(), action: ErrorAction::IgnoreError});
+               }
+
+               let utxo_value = match &chain_access {
+                       &None => {
+                               // Tentatively accept, potentially exposing us to DoS attacks
+                               None
+                       },
+                       &Some(ref chain_access) => {
+                               match chain_access.get_utxo(&msg.chain_hash, msg.short_channel_id) {
+                                       Ok(TxOut { value, script_pubkey }) => {
+                                               let expected_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
+                                                                                   .push_slice(&msg.bitcoin_key_1.serialize())
+                                                                                   .push_slice(&msg.bitcoin_key_2.serialize())
+                                                                                   .push_opcode(opcodes::all::OP_PUSHNUM_2)
+                                                                                   .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
+                                               if script_pubkey != expected_script {
+                                                       return Err(LightningError{err: format!("Channel announcement key ({}) didn't match on-chain script ({})", script_pubkey.to_hex(), expected_script.to_hex()), action: ErrorAction::IgnoreError});
+                                               }
+                                               //TODO: Check if value is worth storing, use it to inform routing, and compare it
+                                               //to the new HTLC max field in channel_update
+                                               Some(value)
+                                       },
+                                       Err(chain::AccessError::UnknownChain) => {
+                                               return Err(LightningError{err: format!("Channel announced on an unknown chain ({})", msg.chain_hash.encode().to_hex()), action: ErrorAction::IgnoreError});
+                                       },
+                                       Err(chain::AccessError::UnknownTx) => {
+                                               return Err(LightningError{err: "Channel announced without corresponding UTXO entry".to_owned(), action: ErrorAction::IgnoreError});
+                                       },
+                               }
+                       },
+               };
+
+               #[allow(unused_mut, unused_assignments)]
+               let mut announcement_received_time = 0;
+               #[cfg(feature = "std")]
+               {
+                       announcement_received_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+               }
+
+               let chan_info = ChannelInfo {
+                       features: msg.features.clone(),
+                       node_one: NodeId::from_pubkey(&msg.node_id_1),
+                       one_to_two: None,
+                       node_two: NodeId::from_pubkey(&msg.node_id_2),
+                       two_to_one: None,
+                       capacity_sats: utxo_value,
+                       announcement_message: if msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY
+                               { full_msg.cloned() } else { None },
+                       announcement_received_time,
+               };
+
+               self.add_channel_between_nodes(msg.short_channel_id, chan_info, utxo_value)
+       }
+
+       /// Marks a channel in the graph as failed if a corresponding HTLC fail was sent.
+       /// If permanent, removes a channel from the local storage.
+       /// May cause the removal of nodes too, if this was their last channel.
+       /// If not permanent, makes channels unavailable for routing.
+       pub fn channel_failed(&self, short_channel_id: u64, is_permanent: bool) {
+               let mut channels = self.channels.write().unwrap();
+               if is_permanent {
+                       if let Some(chan) = channels.remove(&short_channel_id) {
+                               let mut nodes = self.nodes.write().unwrap();
+                               Self::remove_channel_in_nodes(&mut nodes, &chan, short_channel_id);
+                       }
+               } else {
+                       if let Some(chan) = channels.get_mut(&short_channel_id) {
+                               if let Some(one_to_two) = chan.one_to_two.as_mut() {
+                                       one_to_two.enabled = false;
+                               }
+                               if let Some(two_to_one) = chan.two_to_one.as_mut() {
+                                       two_to_one.enabled = false;
+                               }
+                       }
+               }
+       }
+
+       /// Marks a node in the graph as failed.
+       pub fn node_failed(&self, _node_id: &PublicKey, is_permanent: bool) {
+               if is_permanent {
+                       // TODO: Wholly remove the node
+               } else {
+                       // TODO: downgrade the node
+               }
+       }
+
+       #[cfg(feature = "std")]
+       /// Removes information about channels that we haven't heard any updates about in some time.
+       /// This can be used regularly to prune the network graph of channels that likely no longer
+       /// exist.
+       ///
+       /// While there is no formal requirement that nodes regularly re-broadcast their channel
+       /// updates every two weeks, the non-normative section of BOLT 7 currently suggests that
+       /// pruning occur for updates which are at least two weeks old, which we implement here.
+       ///
+       /// Note that for users of the `lightning-background-processor` crate this method may be
+       /// automatically called regularly for you.
+       ///
+       /// This method is only available with the `std` feature. See
+       /// [`NetworkGraph::remove_stale_channels_with_time`] for `no-std` use.
+       pub fn remove_stale_channels(&self) {
+               let time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+               self.remove_stale_channels_with_time(time);
+       }
+
+       /// Removes information about channels that we haven't heard any updates about in some time.
+       /// This can be used regularly to prune the network graph of channels that likely no longer
+       /// exist.
+       ///
+       /// While there is no formal requirement that nodes regularly re-broadcast their channel
+       /// updates every two weeks, the non-normative section of BOLT 7 currently suggests that
+       /// pruning occur for updates which are at least two weeks old, which we implement here.
+       ///
+       /// This function takes the current unix time as an argument. For users with the `std` feature
+       /// enabled, [`NetworkGraph::remove_stale_channels`] may be preferable.
+       pub fn remove_stale_channels_with_time(&self, current_time_unix: u64) {
+               let mut channels = self.channels.write().unwrap();
+               // Time out if we haven't received an update in at least 14 days.
+               if current_time_unix > u32::max_value() as u64 { return; } // Remove by 2106
+               if current_time_unix < STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS { return; }
+               let min_time_unix: u32 = (current_time_unix - STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS) as u32;
+               // Sadly BTreeMap::retain was only stabilized in 1.53 so we can't switch to it for some
+               // time.
+               let mut scids_to_remove = Vec::new();
+               for (scid, info) in channels.iter_mut() {
+                       if info.one_to_two.is_some() && info.one_to_two.as_ref().unwrap().last_update < min_time_unix {
+                               info.one_to_two = None;
+                       }
+                       if info.two_to_one.is_some() && info.two_to_one.as_ref().unwrap().last_update < min_time_unix {
+                               info.two_to_one = None;
+                       }
+                       if info.one_to_two.is_none() && info.two_to_one.is_none() {
+                               // We check the announcement_received_time here to ensure we don't drop
+                               // announcements that we just received and are just waiting for our peer to send a
+                               // channel_update for.
+                               if info.announcement_received_time < min_time_unix as u64 {
+                                       scids_to_remove.push(*scid);
+                               }
+                       }
+               }
+               if !scids_to_remove.is_empty() {
+                       let mut nodes = self.nodes.write().unwrap();
+                       for scid in scids_to_remove {
+                               let info = channels.remove(&scid).expect("We just accessed this scid, it should be present");
+                               Self::remove_channel_in_nodes(&mut nodes, &info, scid);
+                       }
+               }
+       }
+
+       /// For an already known (from announcement) channel, update info about one of the directions
+       /// of the channel.
+       ///
+       /// You probably don't want to call this directly, instead relying on a P2PGossipSync's
+       /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
+       /// routing messages from a source using a protocol other than the lightning P2P protocol.
+       ///
+       /// If built with `no-std`, any updates with a timestamp more than two weeks in the past or
+       /// materially in the future will be rejected.
+       pub fn update_channel<T: secp256k1::Verification>(&self, msg: &msgs::ChannelUpdate, secp_ctx: &Secp256k1<T>) -> Result<(), LightningError> {
+               self.update_channel_intern(&msg.contents, Some(&msg), Some((&msg.signature, secp_ctx)))
+       }
+
+       /// For an already known (from announcement) channel, update info about one of the directions
+       /// of the channel without verifying the associated signatures. Because we aren't given the
+       /// associated signatures here we cannot relay the channel update to any of our peers.
+       ///
+       /// If built with `no-std`, any updates with a timestamp more than two weeks in the past or
+       /// materially in the future will be rejected.
+       pub fn update_channel_unsigned(&self, msg: &msgs::UnsignedChannelUpdate) -> Result<(), LightningError> {
+               self.update_channel_intern(msg, None, None::<(&secp256k1::ecdsa::Signature, &Secp256k1<secp256k1::VerifyOnly>)>)
+       }
+
+       fn update_channel_intern<T: secp256k1::Verification>(&self, msg: &msgs::UnsignedChannelUpdate, full_msg: Option<&msgs::ChannelUpdate>, sig_info: Option<(&secp256k1::ecdsa::Signature, &Secp256k1<T>)>) -> Result<(), LightningError> {
+               let dest_node_id;
+               let chan_enabled = msg.flags & (1 << 1) != (1 << 1);
+               let chan_was_enabled;
+
+               #[cfg(all(feature = "std", not(test), not(feature = "_test_utils")))]
+               {
+                       // Note that many tests rely on being able to set arbitrarily old timestamps, thus we
+                       // disable this check during tests!
+                       let time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+                       if (msg.timestamp as u64) < time - STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS {
+                               return Err(LightningError{err: "channel_update is older than two weeks old".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                       }
+                       if msg.timestamp as u64 > time + 60 * 60 * 24 {
+                               return Err(LightningError{err: "channel_update has a timestamp more than a day in the future".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                       }
+               }
+
+               let mut channels = self.channels.write().unwrap();
+               match channels.get_mut(&msg.short_channel_id) {
+                       None => return Err(LightningError{err: "Couldn't find channel for update".to_owned(), action: ErrorAction::IgnoreError}),
+                       Some(channel) => {
+                               if let OptionalField::Present(htlc_maximum_msat) = msg.htlc_maximum_msat {
+                                       if htlc_maximum_msat > MAX_VALUE_MSAT {
+                                               return Err(LightningError{err: "htlc_maximum_msat is larger than maximum possible msats".to_owned(), action: ErrorAction::IgnoreError});
+                                       }
+
+                                       if let Some(capacity_sats) = channel.capacity_sats {
+                                               // It's possible channel capacity is available now, although it wasn't available at announcement (so the field is None).
+                                               // Don't query UTXO set here to reduce DoS risks.
+                                               if capacity_sats > MAX_VALUE_MSAT / 1000 || htlc_maximum_msat > capacity_sats * 1000 {
+                                                       return Err(LightningError{err: "htlc_maximum_msat is larger than channel capacity or capacity is bogus".to_owned(), action: ErrorAction::IgnoreError});
+                                               }
+                                       }
+                               }
+                               macro_rules! check_update_latest {
+                                       ($target: expr) => {
+                                               if let Some(existing_chan_info) = $target.as_ref() {
+                                                       // The timestamp field is somewhat of a misnomer - the BOLTs use it to
+                                                       // order updates to ensure you always have the latest one, only
+                                                       // suggesting  that it be at least the current time. For
+                                                       // channel_updates specifically, the BOLTs discuss the possibility of
+                                                       // pruning based on the timestamp field being more than two weeks old,
+                                                       // but only in the non-normative section.
+                                                       if existing_chan_info.last_update > msg.timestamp {
+                                                               return Err(LightningError{err: "Update older than last processed update".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                                                       } else if existing_chan_info.last_update == msg.timestamp {
+                                                               return Err(LightningError{err: "Update had same timestamp as last processed update".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
+                                                       }
+                                                       chan_was_enabled = existing_chan_info.enabled;
+                                               } else {
+                                                       chan_was_enabled = false;
+                                               }
+                                       }
+                               }
+
+                               macro_rules! get_new_channel_info {
+                                       () => { {
+                                               let last_update_message = if msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY
+                                                       { full_msg.cloned() } else { None };
+
+                                               let updated_channel_update_info = ChannelUpdateInfo {
+                                                       enabled: chan_enabled,
+                                                       last_update: msg.timestamp,
+                                                       cltv_expiry_delta: msg.cltv_expiry_delta,
+                                                       htlc_minimum_msat: msg.htlc_minimum_msat,
+                                                       htlc_maximum_msat: if let OptionalField::Present(max_value) = msg.htlc_maximum_msat { Some(max_value) } else { None },
+                                                       fees: RoutingFees {
+                                                               base_msat: msg.fee_base_msat,
+                                                               proportional_millionths: msg.fee_proportional_millionths,
+                                                       },
+                                                       last_update_message
+                                               };
+                                               Some(updated_channel_update_info)
+                                       } }
+                               }
+
+                               let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
+                               if msg.flags & 1 == 1 {
+                                       dest_node_id = channel.node_one.clone();
+                                       check_update_latest!(channel.two_to_one);
+                                       if let Some((sig, ctx)) = sig_info {
+                                               secp_verify_sig!(ctx, &msg_hash, &sig, &PublicKey::from_slice(channel.node_two.as_slice()).map_err(|_| LightningError{
+                                                       err: "Couldn't parse source node pubkey".to_owned(),
+                                                       action: ErrorAction::IgnoreAndLog(Level::Debug)
+                                               })?, "channel_update");
+                                       }
+                                       channel.two_to_one = get_new_channel_info!();
+                               } else {
+                                       dest_node_id = channel.node_two.clone();
+                                       check_update_latest!(channel.one_to_two);
+                                       if let Some((sig, ctx)) = sig_info {
+                                               secp_verify_sig!(ctx, &msg_hash, &sig, &PublicKey::from_slice(channel.node_one.as_slice()).map_err(|_| LightningError{
+                                                       err: "Couldn't parse destination node pubkey".to_owned(),
+                                                       action: ErrorAction::IgnoreAndLog(Level::Debug)
+                                               })?, "channel_update");
+                                       }
+                                       channel.one_to_two = get_new_channel_info!();
+                               }
+                       }
+               }
+
+               let mut nodes = self.nodes.write().unwrap();
+               if chan_enabled {
+                       let node = nodes.get_mut(&dest_node_id).unwrap();
+                       let mut base_msat = msg.fee_base_msat;
+                       let mut proportional_millionths = msg.fee_proportional_millionths;
+                       if let Some(fees) = node.lowest_inbound_channel_fees {
+                               base_msat = cmp::min(base_msat, fees.base_msat);
+                               proportional_millionths = cmp::min(proportional_millionths, fees.proportional_millionths);
+                       }
+                       node.lowest_inbound_channel_fees = Some(RoutingFees {
+                               base_msat,
+                               proportional_millionths
+                       });
+               } else if chan_was_enabled {
+                       let node = nodes.get_mut(&dest_node_id).unwrap();
+                       let mut lowest_inbound_channel_fees = None;
+
+                       for chan_id in node.channels.iter() {
+                               let chan = channels.get(chan_id).unwrap();
+                               let chan_info_opt;
+                               if chan.node_one == dest_node_id {
+                                       chan_info_opt = chan.two_to_one.as_ref();
+                               } else {
+                                       chan_info_opt = chan.one_to_two.as_ref();
+                               }
+                               if let Some(chan_info) = chan_info_opt {
+                                       if chan_info.enabled {
+                                               let fees = lowest_inbound_channel_fees.get_or_insert(RoutingFees {
+                                                       base_msat: u32::max_value(), proportional_millionths: u32::max_value() });
+                                               fees.base_msat = cmp::min(fees.base_msat, chan_info.fees.base_msat);
+                                               fees.proportional_millionths = cmp::min(fees.proportional_millionths, chan_info.fees.proportional_millionths);
+                                       }
+                               }
+                       }
+
+                       node.lowest_inbound_channel_fees = lowest_inbound_channel_fees;
+               }
+
+               Ok(())
+       }
+
+       fn remove_channel_in_nodes(nodes: &mut BTreeMap<NodeId, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
+               macro_rules! remove_from_node {
+                       ($node_id: expr) => {
+                               if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
+                                       entry.get_mut().channels.retain(|chan_id| {
+                                               short_channel_id != *chan_id
+                                       });
+                                       if entry.get().channels.is_empty() {
+                                               entry.remove_entry();
+                                       }
+                               } else {
+                                       panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
+                               }
+                       }
+               }
+
+               remove_from_node!(chan.node_one);
+               remove_from_node!(chan.node_two);
+       }
+}
+
+impl ReadOnlyNetworkGraph<'_> {
+       /// Returns all known valid channels' short ids along with announced channel info.
+       ///
+       /// (C-not exported) because we have no mapping for `BTreeMap`s
+       pub fn channels(&self) -> &BTreeMap<u64, ChannelInfo> {
+               &*self.channels
+       }
+
+       /// Returns all known nodes' public keys along with announced node info.
+       ///
+       /// (C-not exported) because we have no mapping for `BTreeMap`s
+       pub fn nodes(&self) -> &BTreeMap<NodeId, NodeInfo> {
+               &*self.nodes
+       }
+
+       /// Get network addresses by node id.
+       /// Returns None if the requested node is completely unknown,
+       /// or if node announcement for the node was never received.
+       pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
+               if let Some(node) = self.nodes.get(&NodeId::from_pubkey(&pubkey)) {
+                       if let Some(node_info) = node.announcement_info.as_ref() {
+                               return Some(node_info.addresses.clone())
+                       }
+               }
+               None
+       }
+}
+
+#[cfg(test)]
+mod tests {
+       use chain;
+       use ln::PaymentHash;
+       use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
+       use routing::gossip::{P2PGossipSync, NetworkGraph, NetworkUpdate, MAX_EXCESS_BYTES_FOR_RELAY};
+       use ln::msgs::{Init, OptionalField, RoutingMessageHandler, UnsignedNodeAnnouncement, NodeAnnouncement,
+               UnsignedChannelAnnouncement, ChannelAnnouncement, UnsignedChannelUpdate, ChannelUpdate,
+               ReplyChannelRange, QueryChannelRange, QueryShortChannelIds, MAX_VALUE_MSAT};
+       use util::test_utils;
+       use util::logger::Logger;
+       use util::ser::{Readable, Writeable};
+       use util::events::{Event, EventHandler, MessageSendEvent, MessageSendEventsProvider};
+       use util::scid_utils::scid_from_parts;
+
+       use super::STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS;
+
+       use bitcoin::hashes::sha256d::Hash as Sha256dHash;
+       use bitcoin::hashes::Hash;
+       use bitcoin::network::constants::Network;
+       use bitcoin::blockdata::constants::genesis_block;
+       use bitcoin::blockdata::script::{Builder, Script};
+       use bitcoin::blockdata::transaction::TxOut;
+       use bitcoin::blockdata::opcodes;
+
+       use hex;
+
+       use bitcoin::secp256k1::{PublicKey, SecretKey};
+       use bitcoin::secp256k1::{All, Secp256k1};
+
+       use io;
+       use bitcoin::secp256k1;
+       use prelude::*;
+       use sync::Arc;
+
+       fn create_network_graph() -> NetworkGraph {
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               NetworkGraph::new(genesis_hash)
+       }
+
+       fn create_gossip_sync(network_graph: &NetworkGraph) -> (
+               Secp256k1<All>, P2PGossipSync<&NetworkGraph, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>
+       ) {
+               let secp_ctx = Secp256k1::new();
+               let logger = Arc::new(test_utils::TestLogger::new());
+               let gossip_sync = P2PGossipSync::new(network_graph, None, Arc::clone(&logger));
+               (secp_ctx, gossip_sync)
+       }
+
+       #[test]
+       fn request_full_sync_finite_times() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+               let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
+
+               assert!(gossip_sync.should_request_full_sync(&node_id));
+               assert!(gossip_sync.should_request_full_sync(&node_id));
+               assert!(gossip_sync.should_request_full_sync(&node_id));
+               assert!(gossip_sync.should_request_full_sync(&node_id));
+               assert!(gossip_sync.should_request_full_sync(&node_id));
+               assert!(!gossip_sync.should_request_full_sync(&node_id));
+       }
+
+       fn get_signed_node_announcement<F: Fn(&mut UnsignedNodeAnnouncement)>(f: F, node_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> NodeAnnouncement {
+               let node_id = PublicKey::from_secret_key(&secp_ctx, node_key);
+               let mut unsigned_announcement = UnsignedNodeAnnouncement {
+                       features: NodeFeatures::known(),
+                       timestamp: 100,
+                       node_id: node_id,
+                       rgb: [0; 3],
+                       alias: [0; 32],
+                       addresses: Vec::new(),
+                       excess_address_data: Vec::new(),
+                       excess_data: Vec::new(),
+               };
+               f(&mut unsigned_announcement);
+               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
+               NodeAnnouncement {
+                       signature: secp_ctx.sign_ecdsa(&msghash, node_key),
+                       contents: unsigned_announcement
+               }
+       }
+
+       fn get_signed_channel_announcement<F: Fn(&mut UnsignedChannelAnnouncement)>(f: F, node_1_key: &SecretKey, node_2_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> ChannelAnnouncement {
+               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_key);
+               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_key);
+               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
+               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
+
+               let mut unsigned_announcement = UnsignedChannelAnnouncement {
+                       features: ChannelFeatures::known(),
+                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+                       short_channel_id: 0,
+                       node_id_1,
+                       node_id_2,
+                       bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
+                       bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
+                       excess_data: Vec::new(),
+               };
+               f(&mut unsigned_announcement);
+               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
+               ChannelAnnouncement {
+                       node_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_key),
+                       node_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_key),
+                       bitcoin_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_btckey),
+                       bitcoin_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_btckey),
+                       contents: unsigned_announcement,
+               }
+       }
+
+       fn get_channel_script(secp_ctx: &Secp256k1<secp256k1::All>) -> Script {
+               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
+               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
+               Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
+                             .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_1_btckey).serialize())
+                             .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_2_btckey).serialize())
+                             .push_opcode(opcodes::all::OP_PUSHNUM_2)
+                             .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
+                             .to_v0_p2wsh()
+       }
+
+       fn get_signed_channel_update<F: Fn(&mut UnsignedChannelUpdate)>(f: F, node_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> ChannelUpdate {
+               let mut unsigned_channel_update = UnsignedChannelUpdate {
+                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+                       short_channel_id: 0,
+                       timestamp: 100,
+                       flags: 0,
+                       cltv_expiry_delta: 144,
+                       htlc_minimum_msat: 1_000_000,
+                       htlc_maximum_msat: OptionalField::Absent,
+                       fee_base_msat: 10_000,
+                       fee_proportional_millionths: 20,
+                       excess_data: Vec::new()
+               };
+               f(&mut unsigned_channel_update);
+               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
+               ChannelUpdate {
+                       signature: secp_ctx.sign_ecdsa(&msghash, node_key),
+                       contents: unsigned_channel_update
+               }
+       }
+
+       #[test]
+       fn handling_node_announcements() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+               let zero_hash = Sha256dHash::hash(&[0; 32]);
+
+               let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_node_announcement(&valid_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!("No existing channels for node_announcement", e.err)
+               };
+
+               {
+                       // Announce a channel to add a corresponding node.
+                       let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                               Ok(res) => assert!(res),
+                               _ => panic!()
+                       };
+               }
+
+               match gossip_sync.handle_node_announcement(&valid_announcement) {
+                       Ok(res) => assert!(res),
+                       Err(_) => panic!()
+               };
+
+               let fake_msghash = hash_to_message!(&zero_hash);
+               match gossip_sync.handle_node_announcement(
+                       &NodeAnnouncement {
+                               signature: secp_ctx.sign_ecdsa(&fake_msghash, node_1_privkey),
+                               contents: valid_announcement.contents.clone()
+               }) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Invalid signature on node_announcement message")
+               };
+
+               let announcement_with_data = get_signed_node_announcement(|unsigned_announcement| {
+                       unsigned_announcement.timestamp += 1000;
+                       unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
+               }, node_1_privkey, &secp_ctx);
+               // Return false because contains excess data.
+               match gossip_sync.handle_node_announcement(&announcement_with_data) {
+                       Ok(res) => assert!(!res),
+                       Err(_) => panic!()
+               };
+
+               // Even though previous announcement was not relayed further, we still accepted it,
+               // so we now won't accept announcements before the previous one.
+               let outdated_announcement = get_signed_node_announcement(|unsigned_announcement| {
+                       unsigned_announcement.timestamp += 1000 - 10;
+               }, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_node_announcement(&outdated_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Update older than last processed update")
+               };
+       }
+
+       #[test]
+       fn handling_channel_announcements() {
+               let secp_ctx = Secp256k1::new();
+               let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               let good_script = get_channel_script(&secp_ctx);
+               let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+
+               // Test if the UTXO lookups were not supported
+               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
+               let mut gossip_sync = P2PGossipSync::new(&network_graph, None, Arc::clone(&logger));
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(res) => assert!(res),
+                       _ => panic!()
+               };
+
+               {
+                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
+                               None => panic!(),
+                               Some(_) => ()
+                       };
+               }
+
+               // If we receive announcement for the same channel (with UTXO lookups disabled),
+               // drop new one on the floor, since we can't see any changes.
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Already have knowledge of channel")
+               };
+
+               // Test if an associated transaction were not on-chain (or not confirmed).
+               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
+               *chain_source.utxo_ret.lock().unwrap() = Err(chain::AccessError::UnknownTx);
+               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
+               gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), Arc::clone(&logger));
+
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.short_channel_id += 1;
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Channel announced without corresponding UTXO entry")
+               };
+
+               // Now test if the transaction is found in the UTXO set and the script is correct.
+               *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: 0, script_pubkey: good_script.clone() });
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.short_channel_id += 2;
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(res) => assert!(res),
+                       _ => panic!()
+               };
+
+               {
+                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
+                               None => panic!(),
+                               Some(_) => ()
+                       };
+               }
+
+               // If we receive announcement for the same channel (but TX is not confirmed),
+               // drop new one on the floor, since we can't see any changes.
+               *chain_source.utxo_ret.lock().unwrap() = Err(chain::AccessError::UnknownTx);
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Channel announced without corresponding UTXO entry")
+               };
+
+               // But if it is confirmed, replace the channel
+               *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: 0, script_pubkey: good_script });
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.features = ChannelFeatures::empty();
+                       unsigned_announcement.short_channel_id += 2;
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(res) => assert!(res),
+                       _ => panic!()
+               };
+               {
+                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
+                               Some(channel_entry) => {
+                                       assert_eq!(channel_entry.features, ChannelFeatures::empty());
+                               },
+                               _ => panic!()
+                       };
+               }
+
+               // Don't relay valid channels with excess data
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.short_channel_id += 3;
+                       unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(res) => assert!(!res),
+                       _ => panic!()
+               };
+
+               let mut invalid_sig_announcement = valid_announcement.clone();
+               invalid_sig_announcement.contents.excess_data = Vec::new();
+               match gossip_sync.handle_channel_announcement(&invalid_sig_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Invalid signature on channel_announcement message")
+               };
+
+               let channel_to_itself_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_announcement(&channel_to_itself_announcement) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Channel announcement node had a channel with itself")
+               };
+       }
+
+       #[test]
+       fn handling_channel_update() {
+               let secp_ctx = Secp256k1::new();
+               let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
+               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
+               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
+               let gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), Arc::clone(&logger));
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               let amount_sats = 1000_000;
+               let short_channel_id;
+
+               {
+                       // Announce a channel we will update
+                       let good_script = get_channel_script(&secp_ctx);
+                       *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: amount_sats, script_pubkey: good_script.clone() });
+
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
+                       match gossip_sync.handle_channel_announcement(&valid_channel_announcement) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+
+               }
+
+               let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
+                       Ok(res) => assert!(res),
+                       _ => panic!()
+               };
+
+               {
+                       match network_graph.read_only().channels().get(&short_channel_id) {
+                               None => panic!(),
+                               Some(channel_info) => {
+                                       assert_eq!(channel_info.one_to_two.as_ref().unwrap().cltv_expiry_delta, 144);
+                                       assert!(channel_info.two_to_one.is_none());
+                               }
+                       };
+               }
+
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 100;
+                       unsigned_channel_update.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
+               }, node_1_privkey, &secp_ctx);
+               // Return false because contains excess data
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
+                       Ok(res) => assert!(!res),
+                       _ => panic!()
+               };
+
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 110;
+                       unsigned_channel_update.short_channel_id += 1;
+               }, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Couldn't find channel for update")
+               };
+
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(MAX_VALUE_MSAT + 1);
+                       unsigned_channel_update.timestamp += 110;
+               }, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "htlc_maximum_msat is larger than maximum possible msats")
+               };
+
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(amount_sats * 1000 + 1);
+                       unsigned_channel_update.timestamp += 110;
+               }, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "htlc_maximum_msat is larger than channel capacity or capacity is bogus")
+               };
+
+               // Even though previous update was not relayed further, we still accepted it,
+               // so we now won't accept update before the previous one.
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 100;
+               }, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_update(&valid_channel_update) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Update had same timestamp as last processed update")
+               };
+
+               let mut invalid_sig_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 500;
+               }, node_1_privkey, &secp_ctx);
+               let zero_hash = Sha256dHash::hash(&[0; 32]);
+               let fake_msghash = hash_to_message!(&zero_hash);
+               invalid_sig_channel_update.signature = secp_ctx.sign_ecdsa(&fake_msghash, node_1_privkey);
+               match gossip_sync.handle_channel_update(&invalid_sig_channel_update) {
+                       Ok(_) => panic!(),
+                       Err(e) => assert_eq!(e.err, "Invalid signature on channel_update message")
+               };
+       }
+
+       #[test]
+       fn handling_network_update() {
+               let logger = test_utils::TestLogger::new();
+               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               let network_graph = NetworkGraph::new(genesis_hash);
+               let gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), &logger);
+               let secp_ctx = Secp256k1::new();
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               {
+                       // There is no nodes in the table at the beginning.
+                       assert_eq!(network_graph.read_only().nodes().len(), 0);
+               }
+
+               let short_channel_id;
+               {
+                       // Announce a channel we will update
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
+                       let chain_source: Option<&test_utils::TestChainSource> = None;
+                       assert!(network_graph.update_channel_from_announcement(&valid_channel_announcement, &chain_source, &secp_ctx).is_ok());
+                       assert!(network_graph.read_only().channels().get(&short_channel_id).is_some());
+
+                       let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
+                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_none());
+
+                       gossip_sync.handle_event(&Event::PaymentPathFailed {
+                               payment_id: None,
+                               payment_hash: PaymentHash([0; 32]),
+                               rejected_by_dest: false,
+                               all_paths_failed: true,
+                               path: vec![],
+                               network_update: Some(NetworkUpdate::ChannelUpdateMessage {
+                                       msg: valid_channel_update,
+                               }),
+                               short_channel_id: None,
+                               retry: None,
+                               error_code: None,
+                               error_data: None,
+                       });
+
+                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_some());
+               }
+
+               // Non-permanent closing just disables a channel
+               {
+                       match network_graph.read_only().channels().get(&short_channel_id) {
+                               None => panic!(),
+                               Some(channel_info) => {
+                                       assert!(channel_info.one_to_two.as_ref().unwrap().enabled);
+                               }
+                       };
+
+                       gossip_sync.handle_event(&Event::PaymentPathFailed {
+                               payment_id: None,
+                               payment_hash: PaymentHash([0; 32]),
+                               rejected_by_dest: false,
+                               all_paths_failed: true,
+                               path: vec![],
+                               network_update: Some(NetworkUpdate::ChannelFailure {
+                                       short_channel_id,
+                                       is_permanent: false,
+                               }),
+                               short_channel_id: None,
+                               retry: None,
+                               error_code: None,
+                               error_data: None,
+                       });
+
+                       match network_graph.read_only().channels().get(&short_channel_id) {
+                               None => panic!(),
+                               Some(channel_info) => {
+                                       assert!(!channel_info.one_to_two.as_ref().unwrap().enabled);
+                               }
+                       };
+               }
+
+               // Permanent closing deletes a channel
+               gossip_sync.handle_event(&Event::PaymentPathFailed {
+                       payment_id: None,
+                       payment_hash: PaymentHash([0; 32]),
+                       rejected_by_dest: false,
+                       all_paths_failed: true,
+                       path: vec![],
+                       network_update: Some(NetworkUpdate::ChannelFailure {
+                               short_channel_id,
+                               is_permanent: true,
+                       }),
+                       short_channel_id: None,
+                       retry: None,
+                       error_code: None,
+                       error_data: None,
+               });
+
+               assert_eq!(network_graph.read_only().channels().len(), 0);
+               // Nodes are also deleted because there are no associated channels anymore
+               assert_eq!(network_graph.read_only().nodes().len(), 0);
+               // TODO: Test NetworkUpdate::NodeFailure, which is not implemented yet.
+       }
+
+       #[test]
+       fn test_channel_timeouts() {
+               // Test the removal of channels with `remove_stale_channels`.
+               let logger = test_utils::TestLogger::new();
+               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               let network_graph = NetworkGraph::new(genesis_hash);
+               let gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), &logger);
+               let secp_ctx = Secp256k1::new();
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+               let short_channel_id = valid_channel_announcement.contents.short_channel_id;
+               let chain_source: Option<&test_utils::TestChainSource> = None;
+               assert!(network_graph.update_channel_from_announcement(&valid_channel_announcement, &chain_source, &secp_ctx).is_ok());
+               assert!(network_graph.read_only().channels().get(&short_channel_id).is_some());
+
+               let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
+               assert!(gossip_sync.handle_channel_update(&valid_channel_update).is_ok());
+               assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_some());
+
+               network_graph.remove_stale_channels_with_time(100 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
+               assert_eq!(network_graph.read_only().channels().len(), 1);
+               assert_eq!(network_graph.read_only().nodes().len(), 2);
+
+               network_graph.remove_stale_channels_with_time(101 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
+               #[cfg(feature = "std")]
+               {
+                       // In std mode, a further check is performed before fully removing the channel -
+                       // the channel_announcement must have been received at least two weeks ago. We
+                       // fudge that here by indicating the time has jumped two weeks. Note that the
+                       // directional channel information will have been removed already..
+                       assert_eq!(network_graph.read_only().channels().len(), 1);
+                       assert_eq!(network_graph.read_only().nodes().len(), 2);
+                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_none());
+
+                       use std::time::{SystemTime, UNIX_EPOCH};
+                       let announcement_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+                       network_graph.remove_stale_channels_with_time(announcement_time + 1 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
+               }
+
+               assert_eq!(network_graph.read_only().channels().len(), 0);
+               assert_eq!(network_graph.read_only().nodes().len(), 0);
+       }
+
+       #[test]
+       fn getting_next_channel_announcements() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               // Channels were not announced yet.
+               let channels_with_announcements = gossip_sync.get_next_channel_announcements(0, 1);
+               assert_eq!(channels_with_announcements.len(), 0);
+
+               let short_channel_id;
+               {
+                       // Announce a channel we will update
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
+                       match gossip_sync.handle_channel_announcement(&valid_channel_announcement) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+               }
+
+               // Contains initial channel announcement now.
+               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id, 1);
+               assert_eq!(channels_with_announcements.len(), 1);
+               if let Some(channel_announcements) = channels_with_announcements.first() {
+                       let &(_, ref update_1, ref update_2) = channel_announcements;
+                       assert_eq!(update_1, &None);
+                       assert_eq!(update_2, &None);
+               } else {
+                       panic!();
+               }
+
+
+               {
+                       // Valid channel update
+                       let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                               unsigned_channel_update.timestamp = 101;
+                       }, node_1_privkey, &secp_ctx);
+                       match gossip_sync.handle_channel_update(&valid_channel_update) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+               }
+
+               // Now contains an initial announcement and an update.
+               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id, 1);
+               assert_eq!(channels_with_announcements.len(), 1);
+               if let Some(channel_announcements) = channels_with_announcements.first() {
+                       let &(_, ref update_1, ref update_2) = channel_announcements;
+                       assert_ne!(update_1, &None);
+                       assert_eq!(update_2, &None);
+               } else {
+                       panic!();
+               }
+
+               {
+                       // Channel update with excess data.
+                       let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                               unsigned_channel_update.timestamp = 102;
+                               unsigned_channel_update.excess_data = [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec();
+                       }, node_1_privkey, &secp_ctx);
+                       match gossip_sync.handle_channel_update(&valid_channel_update) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+               }
+
+               // Test that announcements with excess data won't be returned
+               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id, 1);
+               assert_eq!(channels_with_announcements.len(), 1);
+               if let Some(channel_announcements) = channels_with_announcements.first() {
+                       let &(_, ref update_1, ref update_2) = channel_announcements;
+                       assert_eq!(update_1, &None);
+                       assert_eq!(update_2, &None);
+               } else {
+                       panic!();
+               }
+
+               // Further starting point have no channels after it
+               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id + 1000, 1);
+               assert_eq!(channels_with_announcements.len(), 0);
+       }
+
+       #[test]
+       fn getting_next_node_announcements() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
+
+               // No nodes yet.
+               let next_announcements = gossip_sync.get_next_node_announcements(None, 10);
+               assert_eq!(next_announcements.len(), 0);
+
+               {
+                       // Announce a channel to add 2 nodes
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       match gossip_sync.handle_channel_announcement(&valid_channel_announcement) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+               }
+
+
+               // Nodes were never announced
+               let next_announcements = gossip_sync.get_next_node_announcements(None, 3);
+               assert_eq!(next_announcements.len(), 0);
+
+               {
+                       let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
+                       match gossip_sync.handle_node_announcement(&valid_announcement) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+
+                       let valid_announcement = get_signed_node_announcement(|_| {}, node_2_privkey, &secp_ctx);
+                       match gossip_sync.handle_node_announcement(&valid_announcement) {
+                               Ok(_) => (),
+                               Err(_) => panic!()
+                       };
+               }
+
+               let next_announcements = gossip_sync.get_next_node_announcements(None, 3);
+               assert_eq!(next_announcements.len(), 2);
+
+               // Skip the first node.
+               let next_announcements = gossip_sync.get_next_node_announcements(Some(&node_id_1), 2);
+               assert_eq!(next_announcements.len(), 1);
+
+               {
+                       // Later announcement which should not be relayed (excess data) prevent us from sharing a node
+                       let valid_announcement = get_signed_node_announcement(|unsigned_announcement| {
+                               unsigned_announcement.timestamp += 10;
+                               unsigned_announcement.excess_data = [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec();
+                       }, node_2_privkey, &secp_ctx);
+                       match gossip_sync.handle_node_announcement(&valid_announcement) {
+                               Ok(res) => assert!(!res),
+                               Err(_) => panic!()
+                       };
+               }
+
+               let next_announcements = gossip_sync.get_next_node_announcements(Some(&node_id_1), 2);
+               assert_eq!(next_announcements.len(), 0);
+       }
+
+       #[test]
+       fn network_graph_serialization() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               // Announce a channel to add a corresponding node.
+               let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+               match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                       Ok(res) => assert!(res),
+                       _ => panic!()
+               };
+
+               let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
+               match gossip_sync.handle_node_announcement(&valid_announcement) {
+                       Ok(_) => (),
+                       Err(_) => panic!()
+               };
+
+               let mut w = test_utils::TestVecWriter(Vec::new());
+               assert!(!network_graph.read_only().nodes().is_empty());
+               assert!(!network_graph.read_only().channels().is_empty());
+               network_graph.write(&mut w).unwrap();
+               assert!(<NetworkGraph>::read(&mut io::Cursor::new(&w.0)).unwrap() == network_graph);
+       }
+
+       #[test]
+       fn network_graph_tlv_serialization() {
+               let network_graph = create_network_graph();
+               network_graph.set_last_rapid_gossip_sync_timestamp(42);
+
+               let mut w = test_utils::TestVecWriter(Vec::new());
+               network_graph.write(&mut w).unwrap();
+               let reassembled_network_graph: NetworkGraph = Readable::read(&mut io::Cursor::new(&w.0)).unwrap();
+               assert!(reassembled_network_graph == network_graph);
+               assert_eq!(reassembled_network_graph.get_last_rapid_gossip_sync_timestamp().unwrap(), 42);
+       }
+
+       #[test]
+       #[cfg(feature = "std")]
+       fn calling_sync_routing_table() {
+               use std::time::{SystemTime, UNIX_EPOCH};
+
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+               let node_privkey_1 = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_privkey_1);
+
+               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
+
+               // It should ignore if gossip_queries feature is not enabled
+               {
+                       let init_msg = Init { features: InitFeatures::known().clear_gossip_queries(), remote_network_address: None };
+                       gossip_sync.peer_connected(&node_id_1, &init_msg);
+                       let events = gossip_sync.get_and_clear_pending_msg_events();
+                       assert_eq!(events.len(), 0);
+               }
+
+               // It should send a gossip_timestamp_filter with the correct information
+               {
+                       let init_msg = Init { features: InitFeatures::known(), remote_network_address: None };
+                       gossip_sync.peer_connected(&node_id_1, &init_msg);
+                       let events = gossip_sync.get_and_clear_pending_msg_events();
+                       assert_eq!(events.len(), 1);
+                       match &events[0] {
+                               MessageSendEvent::SendGossipTimestampFilter{ node_id, msg } => {
+                                       assert_eq!(node_id, &node_id_1);
+                                       assert_eq!(msg.chain_hash, chain_hash);
+                                       let expected_timestamp = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+                                       assert!((msg.first_timestamp as u64) >= expected_timestamp - 60*60*24*7*2);
+                                       assert!((msg.first_timestamp as u64) < expected_timestamp - 60*60*24*7*2 + 10);
+                                       assert_eq!(msg.timestamp_range, u32::max_value());
+                               },
+                               _ => panic!("Expected MessageSendEvent::SendChannelRangeQuery")
+                       };
+               }
+       }
+
+       #[test]
+       fn handling_query_channel_range() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+
+               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
+
+               let mut scids: Vec<u64> = vec![
+                       scid_from_parts(0xfffffe, 0xffffff, 0xffff).unwrap(), // max
+                       scid_from_parts(0xffffff, 0xffffff, 0xffff).unwrap(), // never
+               ];
+
+               // used for testing multipart reply across blocks
+               for block in 100000..=108001 {
+                       scids.push(scid_from_parts(block, 0, 0).unwrap());
+               }
+
+               // used for testing resumption on same block
+               scids.push(scid_from_parts(108001, 1, 0).unwrap());
+
+               for scid in scids {
+                       let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                               unsigned_announcement.short_channel_id = scid;
+                       }, node_1_privkey, node_2_privkey, &secp_ctx);
+                       match gossip_sync.handle_channel_announcement(&valid_announcement) {
+                               Ok(_) => (),
+                               _ => panic!()
+                       };
+               }
+
+               // Error when number_of_blocks=0
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 0,
+                               number_of_blocks: 0,
+                       },
+                       false,
+                       vec![ReplyChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 0,
+                               number_of_blocks: 0,
+                               sync_complete: true,
+                               short_channel_ids: vec![]
+                       }]
+               );
+
+               // Error when wrong chain
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: genesis_block(Network::Bitcoin).header.block_hash(),
+                               first_blocknum: 0,
+                               number_of_blocks: 0xffff_ffff,
+                       },
+                       false,
+                       vec![ReplyChannelRange {
+                               chain_hash: genesis_block(Network::Bitcoin).header.block_hash(),
+                               first_blocknum: 0,
+                               number_of_blocks: 0xffff_ffff,
+                               sync_complete: true,
+                               short_channel_ids: vec![],
+                       }]
+               );
+
+               // Error when first_blocknum > 0xffffff
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 0x01000000,
+                               number_of_blocks: 0xffff_ffff,
+                       },
+                       false,
+                       vec![ReplyChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 0x01000000,
+                               number_of_blocks: 0xffff_ffff,
+                               sync_complete: true,
+                               short_channel_ids: vec![]
+                       }]
+               );
+
+               // Empty reply when max valid SCID block num
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 0xffffff,
+                               number_of_blocks: 1,
+                       },
+                       true,
+                       vec![
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 0xffffff,
+                                       number_of_blocks: 1,
+                                       sync_complete: true,
+                                       short_channel_ids: vec![]
+                               },
+                       ]
+               );
+
+               // No results in valid query range
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 1000,
+                               number_of_blocks: 1000,
+                       },
+                       true,
+                       vec![
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 1000,
+                                       number_of_blocks: 1000,
+                                       sync_complete: true,
+                                       short_channel_ids: vec![],
+                               }
+                       ]
+               );
+
+               // Overflow first_blocknum + number_of_blocks
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 0xfe0000,
+                               number_of_blocks: 0xffffffff,
+                       },
+                       true,
+                       vec![
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 0xfe0000,
+                                       number_of_blocks: 0xffffffff - 0xfe0000,
+                                       sync_complete: true,
+                                       short_channel_ids: vec![
+                                               0xfffffe_ffffff_ffff, // max
+                                       ]
+                               }
+                       ]
+               );
+
+               // Single block exactly full
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 100000,
+                               number_of_blocks: 8000,
+                       },
+                       true,
+                       vec![
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 100000,
+                                       number_of_blocks: 8000,
+                                       sync_complete: true,
+                                       short_channel_ids: (100000..=107999)
+                                               .map(|block| scid_from_parts(block, 0, 0).unwrap())
+                                               .collect(),
+                               },
+                       ]
+               );
+
+               // Multiple split on new block
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 100000,
+                               number_of_blocks: 8001,
+                       },
+                       true,
+                       vec![
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 100000,
+                                       number_of_blocks: 7999,
+                                       sync_complete: false,
+                                       short_channel_ids: (100000..=107999)
+                                               .map(|block| scid_from_parts(block, 0, 0).unwrap())
+                                               .collect(),
+                               },
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 107999,
+                                       number_of_blocks: 2,
+                                       sync_complete: true,
+                                       short_channel_ids: vec![
+                                               scid_from_parts(108000, 0, 0).unwrap(),
+                                       ],
+                               }
+                       ]
+               );
+
+               // Multiple split on same block
+               do_handling_query_channel_range(
+                       &gossip_sync,
+                       &node_id_2,
+                       QueryChannelRange {
+                               chain_hash: chain_hash.clone(),
+                               first_blocknum: 100002,
+                               number_of_blocks: 8000,
+                       },
+                       true,
+                       vec![
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 100002,
+                                       number_of_blocks: 7999,
+                                       sync_complete: false,
+                                       short_channel_ids: (100002..=108001)
+                                               .map(|block| scid_from_parts(block, 0, 0).unwrap())
+                                               .collect(),
+                               },
+                               ReplyChannelRange {
+                                       chain_hash: chain_hash.clone(),
+                                       first_blocknum: 108001,
+                                       number_of_blocks: 1,
+                                       sync_complete: true,
+                                       short_channel_ids: vec![
+                                               scid_from_parts(108001, 1, 0).unwrap(),
+                                       ],
+                               }
+                       ]
+               );
+       }
+
+       fn do_handling_query_channel_range(
+               gossip_sync: &P2PGossipSync<&NetworkGraph, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
+               test_node_id: &PublicKey,
+               msg: QueryChannelRange,
+               expected_ok: bool,
+               expected_replies: Vec<ReplyChannelRange>
+       ) {
+               let mut max_firstblocknum = msg.first_blocknum.saturating_sub(1);
+               let mut c_lightning_0_9_prev_end_blocknum = max_firstblocknum;
+               let query_end_blocknum = msg.end_blocknum();
+               let result = gossip_sync.handle_query_channel_range(test_node_id, msg);
+
+               if expected_ok {
+                       assert!(result.is_ok());
+               } else {
+                       assert!(result.is_err());
+               }
+
+               let events = gossip_sync.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), expected_replies.len());
+
+               for i in 0..events.len() {
+                       let expected_reply = &expected_replies[i];
+                       match &events[i] {
+                               MessageSendEvent::SendReplyChannelRange { node_id, msg } => {
+                                       assert_eq!(node_id, test_node_id);
+                                       assert_eq!(msg.chain_hash, expected_reply.chain_hash);
+                                       assert_eq!(msg.first_blocknum, expected_reply.first_blocknum);
+                                       assert_eq!(msg.number_of_blocks, expected_reply.number_of_blocks);
+                                       assert_eq!(msg.sync_complete, expected_reply.sync_complete);
+                                       assert_eq!(msg.short_channel_ids, expected_reply.short_channel_ids);
+
+                                       // Enforce exactly the sequencing requirements present on c-lightning v0.9.3
+                                       assert!(msg.first_blocknum == c_lightning_0_9_prev_end_blocknum || msg.first_blocknum == c_lightning_0_9_prev_end_blocknum.saturating_add(1));
+                                       assert!(msg.first_blocknum >= max_firstblocknum);
+                                       max_firstblocknum = msg.first_blocknum;
+                                       c_lightning_0_9_prev_end_blocknum = msg.first_blocknum.saturating_add(msg.number_of_blocks);
+
+                                       // Check that the last block count is >= the query's end_blocknum
+                                       if i == events.len() - 1 {
+                                               assert!(msg.first_blocknum.saturating_add(msg.number_of_blocks) >= query_end_blocknum);
+                                       }
+                               },
+                               _ => panic!("expected MessageSendEvent::SendReplyChannelRange"),
+                       }
+               }
+       }
+
+       #[test]
+       fn handling_query_short_channel_ids() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
+               let node_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+               let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
+
+               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
+
+               let result = gossip_sync.handle_query_short_channel_ids(&node_id, QueryShortChannelIds {
+                       chain_hash,
+                       short_channel_ids: vec![0x0003e8_000000_0000],
+               });
+               assert!(result.is_err());
+       }
+}
+
+#[cfg(all(test, feature = "_bench_unstable"))]
+mod benches {
+       use super::*;
+
+       use test::Bencher;
+       use std::io::Read;
+
+       #[bench]
+       fn read_network_graph(bench: &mut Bencher) {
+               let mut d = ::routing::router::test_utils::get_route_file().unwrap();
+               let mut v = Vec::new();
+               d.read_to_end(&mut v).unwrap();
+               bench.iter(|| {
+                       let _ = NetworkGraph::read(&mut std::io::Cursor::new(&v)).unwrap();
+               });
+       }
+
+       #[bench]
+       fn write_network_graph(bench: &mut Bencher) {
+               let mut d = ::routing::router::test_utils::get_route_file().unwrap();
+               let net_graph = NetworkGraph::read(&mut d).unwrap();
+               bench.iter(|| {
+                       let _ = net_graph.encode();
+               });
+       }
+}
index a3ab6c0c1b30ff04e50ab5892b91ef358a1980f2..c7babbe3027babb77b878f82768963d7a6319d92 100644 (file)
@@ -9,6 +9,6 @@
 
 //! Structs and impls for receiving messages about the network and storing the topology live here.
 
-pub mod network_graph;
+pub mod gossip;
 pub mod router;
 pub mod scoring;
diff --git a/lightning/src/routing/network_graph.rs b/lightning/src/routing/network_graph.rs
deleted file mode 100644 (file)
index 0fccb32..0000000
+++ /dev/null
@@ -1,2771 +0,0 @@
-// This file is Copyright its original authors, visible in version control
-// history.
-//
-// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
-// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
-// You may not use this file except in accordance with one or both of these
-// licenses.
-
-//! The top-level network map tracking logic lives here.
-
-use bitcoin::secp256k1::constants::PUBLIC_KEY_SIZE;
-use bitcoin::secp256k1::PublicKey;
-use bitcoin::secp256k1::Secp256k1;
-use bitcoin::secp256k1;
-
-use bitcoin::hashes::sha256d::Hash as Sha256dHash;
-use bitcoin::hashes::Hash;
-use bitcoin::blockdata::script::Builder;
-use bitcoin::blockdata::transaction::TxOut;
-use bitcoin::blockdata::opcodes;
-use bitcoin::hash_types::BlockHash;
-
-use chain;
-use chain::Access;
-use ln::features::{ChannelFeatures, NodeFeatures};
-use ln::msgs::{DecodeError, ErrorAction, Init, LightningError, RoutingMessageHandler, NetAddress, MAX_VALUE_MSAT};
-use ln::msgs::{ChannelAnnouncement, ChannelUpdate, NodeAnnouncement, OptionalField, GossipTimestampFilter};
-use ln::msgs::{QueryChannelRange, ReplyChannelRange, QueryShortChannelIds, ReplyShortChannelIdsEnd};
-use ln::msgs;
-use util::ser::{Writeable, Readable, Writer};
-use util::logger::{Logger, Level};
-use util::events::{Event, EventHandler, MessageSendEvent, MessageSendEventsProvider};
-use util::scid_utils::{block_from_scid, scid_from_parts, MAX_SCID_BLOCK};
-
-use io;
-use prelude::*;
-use alloc::collections::{BTreeMap, btree_map::Entry as BtreeEntry};
-use core::{cmp, fmt};
-use sync::{RwLock, RwLockReadGuard};
-use core::sync::atomic::{AtomicUsize, Ordering};
-use sync::Mutex;
-use core::ops::Deref;
-use bitcoin::hashes::hex::ToHex;
-
-#[cfg(feature = "std")]
-use std::time::{SystemTime, UNIX_EPOCH};
-
-/// We remove stale channel directional info two weeks after the last update, per BOLT 7's
-/// suggestion.
-const STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS: u64 = 60 * 60 * 24 * 14;
-
-/// The maximum number of extra bytes which we do not understand in a gossip message before we will
-/// refuse to relay the message.
-const MAX_EXCESS_BYTES_FOR_RELAY: usize = 1024;
-
-/// Maximum number of short_channel_ids that will be encoded in one gossip reply message.
-/// This value ensures a reply fits within the 65k payload limit and is consistent with other implementations.
-const MAX_SCIDS_PER_REPLY: usize = 8000;
-
-/// Represents the compressed public key of a node
-#[derive(Clone, Copy)]
-pub struct NodeId([u8; PUBLIC_KEY_SIZE]);
-
-impl NodeId {
-       /// Create a new NodeId from a public key
-       pub fn from_pubkey(pubkey: &PublicKey) -> Self {
-               NodeId(pubkey.serialize())
-       }
-
-       /// Get the public key slice from this NodeId
-       pub fn as_slice(&self) -> &[u8] {
-               &self.0
-       }
-}
-
-impl fmt::Debug for NodeId {
-       fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-               write!(f, "NodeId({})", log_bytes!(self.0))
-       }
-}
-
-impl core::hash::Hash for NodeId {
-       fn hash<H: core::hash::Hasher>(&self, hasher: &mut H) {
-               self.0.hash(hasher);
-       }
-}
-
-impl Eq for NodeId {}
-
-impl PartialEq for NodeId {
-       fn eq(&self, other: &Self) -> bool {
-               self.0[..] == other.0[..]
-       }
-}
-
-impl cmp::PartialOrd for NodeId {
-       fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
-               Some(self.cmp(other))
-       }
-}
-
-impl Ord for NodeId {
-       fn cmp(&self, other: &Self) -> cmp::Ordering {
-               self.0[..].cmp(&other.0[..])
-       }
-}
-
-impl Writeable for NodeId {
-       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
-               writer.write_all(&self.0)?;
-               Ok(())
-       }
-}
-
-impl Readable for NodeId {
-       fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
-               let mut buf = [0; PUBLIC_KEY_SIZE];
-               reader.read_exact(&mut buf)?;
-               Ok(Self(buf))
-       }
-}
-
-/// Represents the network as nodes and channels between them
-pub struct NetworkGraph {
-       last_rapid_gossip_sync_timestamp: Mutex<Option<u32>>,
-       genesis_hash: BlockHash,
-       // Lock order: channels -> nodes
-       channels: RwLock<BTreeMap<u64, ChannelInfo>>,
-       nodes: RwLock<BTreeMap<NodeId, NodeInfo>>,
-}
-
-impl Clone for NetworkGraph {
-       fn clone(&self) -> Self {
-               let channels = self.channels.read().unwrap();
-               let nodes = self.nodes.read().unwrap();
-               let last_rapid_gossip_sync_timestamp = self.get_last_rapid_gossip_sync_timestamp();
-               Self {
-                       genesis_hash: self.genesis_hash.clone(),
-                       channels: RwLock::new(channels.clone()),
-                       nodes: RwLock::new(nodes.clone()),
-                       last_rapid_gossip_sync_timestamp: Mutex::new(last_rapid_gossip_sync_timestamp)
-               }
-       }
-}
-
-/// A read-only view of [`NetworkGraph`].
-pub struct ReadOnlyNetworkGraph<'a> {
-       channels: RwLockReadGuard<'a, BTreeMap<u64, ChannelInfo>>,
-       nodes: RwLockReadGuard<'a, BTreeMap<NodeId, NodeInfo>>,
-}
-
-/// Update to the [`NetworkGraph`] based on payment failure information conveyed via the Onion
-/// return packet by a node along the route. See [BOLT #4] for details.
-///
-/// [BOLT #4]: https://github.com/lightning/bolts/blob/master/04-onion-routing.md
-#[derive(Clone, Debug, PartialEq)]
-pub enum NetworkUpdate {
-       /// An error indicating a `channel_update` messages should be applied via
-       /// [`NetworkGraph::update_channel`].
-       ChannelUpdateMessage {
-               /// The update to apply via [`NetworkGraph::update_channel`].
-               msg: ChannelUpdate,
-       },
-       /// An error indicating that a channel failed to route a payment, which should be applied via
-       /// [`NetworkGraph::channel_failed`].
-       ChannelFailure {
-               /// The short channel id of the closed channel.
-               short_channel_id: u64,
-               /// Whether the channel should be permanently removed or temporarily disabled until a new
-               /// `channel_update` message is received.
-               is_permanent: bool,
-       },
-       /// An error indicating that a node failed to route a payment, which should be applied via
-       /// [`NetworkGraph::node_failed`].
-       NodeFailure {
-               /// The node id of the failed node.
-               node_id: PublicKey,
-               /// Whether the node should be permanently removed from consideration or can be restored
-               /// when a new `channel_update` message is received.
-               is_permanent: bool,
-       }
-}
-
-impl_writeable_tlv_based_enum_upgradable!(NetworkUpdate,
-       (0, ChannelUpdateMessage) => {
-               (0, msg, required),
-       },
-       (2, ChannelFailure) => {
-               (0, short_channel_id, required),
-               (2, is_permanent, required),
-       },
-       (4, NodeFailure) => {
-               (0, node_id, required),
-               (2, is_permanent, required),
-       },
-);
-
-impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> EventHandler for P2PGossipSync<G, C, L>
-where C::Target: chain::Access, L::Target: Logger {
-       fn handle_event(&self, event: &Event) {
-               if let Event::PaymentPathFailed { payment_hash: _, rejected_by_dest: _, network_update, .. } = event {
-                       if let Some(network_update) = network_update {
-                               self.handle_network_update(network_update);
-                       }
-               }
-       }
-}
-
-/// Receives and validates network updates from peers,
-/// stores authentic and relevant data as a network graph.
-/// This network graph is then used for routing payments.
-/// Provides interface to help with initial routing sync by
-/// serving historical announcements.
-///
-/// Serves as an [`EventHandler`] for applying updates from [`Event::PaymentPathFailed`] to the
-/// [`NetworkGraph`].
-pub struct P2PGossipSync<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref>
-where C::Target: chain::Access, L::Target: Logger
-{
-       secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
-       network_graph: G,
-       chain_access: Option<C>,
-       full_syncs_requested: AtomicUsize,
-       pending_events: Mutex<Vec<MessageSendEvent>>,
-       logger: L,
-}
-
-impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> P2PGossipSync<G, C, L>
-where C::Target: chain::Access, L::Target: Logger
-{
-       /// Creates a new tracker of the actual state of the network of channels and nodes,
-       /// assuming an existing Network Graph.
-       /// Chain monitor is used to make sure announced channels exist on-chain,
-       /// channel data is correct, and that the announcement is signed with
-       /// channel owners' keys.
-       pub fn new(network_graph: G, chain_access: Option<C>, logger: L) -> Self {
-               P2PGossipSync {
-                       secp_ctx: Secp256k1::verification_only(),
-                       network_graph,
-                       full_syncs_requested: AtomicUsize::new(0),
-                       chain_access,
-                       pending_events: Mutex::new(vec![]),
-                       logger,
-               }
-       }
-
-       /// Adds a provider used to check new announcements. Does not affect
-       /// existing announcements unless they are updated.
-       /// Add, update or remove the provider would replace the current one.
-       pub fn add_chain_access(&mut self, chain_access: Option<C>) {
-               self.chain_access = chain_access;
-       }
-
-       /// Gets a reference to the underlying [`NetworkGraph`] which was provided in
-       /// [`P2PGossipSync::new`].
-       ///
-       /// (C-not exported) as bindings don't support a reference-to-a-reference yet
-       pub fn network_graph(&self) -> &G {
-               &self.network_graph
-       }
-
-       /// Returns true when a full routing table sync should be performed with a peer.
-       fn should_request_full_sync(&self, _node_id: &PublicKey) -> bool {
-               //TODO: Determine whether to request a full sync based on the network map.
-               const FULL_SYNCS_TO_REQUEST: usize = 5;
-               if self.full_syncs_requested.load(Ordering::Acquire) < FULL_SYNCS_TO_REQUEST {
-                       self.full_syncs_requested.fetch_add(1, Ordering::AcqRel);
-                       true
-               } else {
-                       false
-               }
-       }
-
-       /// Applies changes to the [`NetworkGraph`] from the given update.
-       fn handle_network_update(&self, update: &NetworkUpdate) {
-               match *update {
-                       NetworkUpdate::ChannelUpdateMessage { ref msg } => {
-                               let short_channel_id = msg.contents.short_channel_id;
-                               let is_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
-                               let status = if is_enabled { "enabled" } else { "disabled" };
-                               log_debug!(self.logger, "Updating channel with channel_update from a payment failure. Channel {} is {}.", short_channel_id, status);
-                               let _ = self.network_graph.update_channel(msg, &self.secp_ctx);
-                       },
-                       NetworkUpdate::ChannelFailure { short_channel_id, is_permanent } => {
-                               let action = if is_permanent { "Removing" } else { "Disabling" };
-                               log_debug!(self.logger, "{} channel graph entry for {} due to a payment failure.", action, short_channel_id);
-                               self.network_graph.channel_failed(short_channel_id, is_permanent);
-                       },
-                       NetworkUpdate::NodeFailure { ref node_id, is_permanent } => {
-                               let action = if is_permanent { "Removing" } else { "Disabling" };
-                               log_debug!(self.logger, "{} node graph entry for {} due to a payment failure.", action, node_id);
-                               self.network_graph.node_failed(node_id, is_permanent);
-                       },
-               }
-       }
-}
-
-macro_rules! secp_verify_sig {
-       ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr, $msg_type: expr ) => {
-               match $secp_ctx.verify_ecdsa($msg, $sig, $pubkey) {
-                       Ok(_) => {},
-                       Err(_) => {
-                               return Err(LightningError {
-                                       err: format!("Invalid signature on {} message", $msg_type),
-                                       action: ErrorAction::SendWarningMessage {
-                                               msg: msgs::WarningMessage {
-                                                       channel_id: [0; 32],
-                                                       data: format!("Invalid signature on {} message", $msg_type),
-                                               },
-                                               log_level: Level::Trace,
-                                       },
-                               });
-                       },
-               }
-       };
-}
-
-impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> RoutingMessageHandler for P2PGossipSync<G, C, L>
-where C::Target: chain::Access, L::Target: Logger
-{
-       fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> {
-               self.network_graph.update_node_from_announcement(msg, &self.secp_ctx)?;
-               Ok(msg.contents.excess_data.len() <=  MAX_EXCESS_BYTES_FOR_RELAY &&
-                  msg.contents.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY &&
-                  msg.contents.excess_data.len() + msg.contents.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY)
-       }
-
-       fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> {
-               self.network_graph.update_channel_from_announcement(msg, &self.chain_access, &self.secp_ctx)?;
-               log_gossip!(self.logger, "Added channel_announcement for {}{}", msg.contents.short_channel_id, if !msg.contents.excess_data.is_empty() { " with excess uninterpreted data!" } else { "" });
-               Ok(msg.contents.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY)
-       }
-
-       fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> {
-               self.network_graph.update_channel(msg, &self.secp_ctx)?;
-               Ok(msg.contents.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY)
-       }
-
-       fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(ChannelAnnouncement, Option<ChannelUpdate>, Option<ChannelUpdate>)> {
-               let mut result = Vec::with_capacity(batch_amount as usize);
-               let channels = self.network_graph.channels.read().unwrap();
-               let mut iter = channels.range(starting_point..);
-               while result.len() < batch_amount as usize {
-                       if let Some((_, ref chan)) = iter.next() {
-                               if chan.announcement_message.is_some() {
-                                       let chan_announcement = chan.announcement_message.clone().unwrap();
-                                       let mut one_to_two_announcement: Option<msgs::ChannelUpdate> = None;
-                                       let mut two_to_one_announcement: Option<msgs::ChannelUpdate> = None;
-                                       if let Some(one_to_two) = chan.one_to_two.as_ref() {
-                                               one_to_two_announcement = one_to_two.last_update_message.clone();
-                                       }
-                                       if let Some(two_to_one) = chan.two_to_one.as_ref() {
-                                               two_to_one_announcement = two_to_one.last_update_message.clone();
-                                       }
-                                       result.push((chan_announcement, one_to_two_announcement, two_to_one_announcement));
-                               } else {
-                                       // TODO: We may end up sending un-announced channel_updates if we are sending
-                                       // initial sync data while receiving announce/updates for this channel.
-                               }
-                       } else {
-                               return result;
-                       }
-               }
-               result
-       }
-
-       fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<NodeAnnouncement> {
-               let mut result = Vec::with_capacity(batch_amount as usize);
-               let nodes = self.network_graph.nodes.read().unwrap();
-               let mut iter = if let Some(pubkey) = starting_point {
-                               let mut iter = nodes.range(NodeId::from_pubkey(pubkey)..);
-                               iter.next();
-                               iter
-                       } else {
-                               nodes.range::<NodeId, _>(..)
-                       };
-               while result.len() < batch_amount as usize {
-                       if let Some((_, ref node)) = iter.next() {
-                               if let Some(node_info) = node.announcement_info.as_ref() {
-                                       if node_info.announcement_message.is_some() {
-                                               result.push(node_info.announcement_message.clone().unwrap());
-                                       }
-                               }
-                       } else {
-                               return result;
-                       }
-               }
-               result
-       }
-
-       /// Initiates a stateless sync of routing gossip information with a peer
-       /// using gossip_queries. The default strategy used by this implementation
-       /// is to sync the full block range with several peers.
-       ///
-       /// We should expect one or more reply_channel_range messages in response
-       /// to our query_channel_range. Each reply will enqueue a query_scid message
-       /// to request gossip messages for each channel. The sync is considered complete
-       /// when the final reply_scids_end message is received, though we are not
-       /// tracking this directly.
-       fn peer_connected(&self, their_node_id: &PublicKey, init_msg: &Init) {
-               // We will only perform a sync with peers that support gossip_queries.
-               if !init_msg.features.supports_gossip_queries() {
-                       return ();
-               }
-
-               // The lightning network's gossip sync system is completely broken in numerous ways.
-               //
-               // Given no broadly-available set-reconciliation protocol, the only reasonable approach is
-               // to do a full sync from the first few peers we connect to, and then receive gossip
-               // updates from all our peers normally.
-               //
-               // Originally, we could simply tell a peer to dump us the entire gossip table on startup,
-               // wasting lots of bandwidth but ensuring we have the full network graph. After the initial
-               // dump peers would always send gossip and we'd stay up-to-date with whatever our peer has
-               // seen.
-               //
-               // In order to reduce the bandwidth waste, "gossip queries" were introduced, allowing you
-               // to ask for the SCIDs of all channels in your peer's routing graph, and then only request
-               // channel data which you are missing. Except there was no way at all to identify which
-               // `channel_update`s you were missing, so you still had to request everything, just in a
-               // very complicated way with some queries instead of just getting the dump.
-               //
-               // Later, an option was added to fetch the latest timestamps of the `channel_update`s to
-               // make efficient sync possible, however it has yet to be implemented in lnd, which makes
-               // relying on it useless.
-               //
-               // After gossip queries were introduced, support for receiving a full gossip table dump on
-               // connection was removed from several nodes, making it impossible to get a full sync
-               // without using the "gossip queries" messages.
-               //
-               // Once you opt into "gossip queries" the only way to receive any gossip updates that a
-               // peer receives after you connect, you must send a `gossip_timestamp_filter` message. This
-               // message, as the name implies, tells the peer to not forward any gossip messages with a
-               // timestamp older than a given value (not the time the peer received the filter, but the
-               // timestamp in the update message, which is often hours behind when the peer received the
-               // message).
-               //
-               // Obnoxiously, `gossip_timestamp_filter` isn't *just* a filter, but its also a request for
-               // your peer to send you the full routing graph (subject to the filter). Thus, in order to
-               // tell a peer to send you any updates as it sees them, you have to also ask for the full
-               // routing graph to be synced. If you set a timestamp filter near the current time, peers
-               // will simply not forward any new updates they see to you which were generated some time
-               // ago (which is not uncommon). If you instead set a timestamp filter near 0 (or two weeks
-               // ago), you will always get the full routing graph from all your peers.
-               //
-               // Most lightning nodes today opt to simply turn off receiving gossip data which only
-               // propagated some time after it was generated, and, worse, often disable gossiping with
-               // several peers after their first connection. The second behavior can cause gossip to not
-               // propagate fully if there are cuts in the gossiping subgraph.
-               //
-               // In an attempt to cut a middle ground between always fetching the full graph from all of
-               // our peers and never receiving gossip from peers at all, we send all of our peers a
-               // `gossip_timestamp_filter`, with the filter time set either two weeks ago or an hour ago.
-               //
-               // For no-std builds, we bury our head in the sand and do a full sync on each connection.
-               let should_request_full_sync = self.should_request_full_sync(&their_node_id);
-               #[allow(unused_mut, unused_assignments)]
-               let mut gossip_start_time = 0;
-               #[cfg(feature = "std")]
-               {
-                       gossip_start_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
-                       if should_request_full_sync {
-                               gossip_start_time -= 60 * 60 * 24 * 7 * 2; // 2 weeks ago
-                       } else {
-                               gossip_start_time -= 60 * 60; // an hour ago
-                       }
-               }
-
-               let mut pending_events = self.pending_events.lock().unwrap();
-               pending_events.push(MessageSendEvent::SendGossipTimestampFilter {
-                       node_id: their_node_id.clone(),
-                       msg: GossipTimestampFilter {
-                               chain_hash: self.network_graph.genesis_hash,
-                               first_timestamp: gossip_start_time as u32, // 2106 issue!
-                               timestamp_range: u32::max_value(),
-                       },
-               });
-       }
-
-       fn handle_reply_channel_range(&self, _their_node_id: &PublicKey, _msg: ReplyChannelRange) -> Result<(), LightningError> {
-               // We don't make queries, so should never receive replies. If, in the future, the set
-               // reconciliation extensions to gossip queries become broadly supported, we should revert
-               // this code to its state pre-0.0.106.
-               Ok(())
-       }
-
-       fn handle_reply_short_channel_ids_end(&self, _their_node_id: &PublicKey, _msg: ReplyShortChannelIdsEnd) -> Result<(), LightningError> {
-               // We don't make queries, so should never receive replies. If, in the future, the set
-               // reconciliation extensions to gossip queries become broadly supported, we should revert
-               // this code to its state pre-0.0.106.
-               Ok(())
-       }
-
-       /// Processes a query from a peer by finding announced/public channels whose funding UTXOs
-       /// are in the specified block range. Due to message size limits, large range
-       /// queries may result in several reply messages. This implementation enqueues
-       /// all reply messages into pending events. Each message will allocate just under 65KiB. A full
-       /// sync of the public routing table with 128k channels will generated 16 messages and allocate ~1MB.
-       /// Logic can be changed to reduce allocation if/when a full sync of the routing table impacts
-       /// memory constrained systems.
-       fn handle_query_channel_range(&self, their_node_id: &PublicKey, msg: QueryChannelRange) -> Result<(), LightningError> {
-               log_debug!(self.logger, "Handling query_channel_range peer={}, first_blocknum={}, number_of_blocks={}", log_pubkey!(their_node_id), msg.first_blocknum, msg.number_of_blocks);
-
-               let inclusive_start_scid = scid_from_parts(msg.first_blocknum as u64, 0, 0);
-
-               // We might receive valid queries with end_blocknum that would overflow SCID conversion.
-               // If so, we manually cap the ending block to avoid this overflow.
-               let exclusive_end_scid = scid_from_parts(cmp::min(msg.end_blocknum() as u64, MAX_SCID_BLOCK), 0, 0);
-
-               // Per spec, we must reply to a query. Send an empty message when things are invalid.
-               if msg.chain_hash != self.network_graph.genesis_hash || inclusive_start_scid.is_err() || exclusive_end_scid.is_err() || msg.number_of_blocks == 0 {
-                       let mut pending_events = self.pending_events.lock().unwrap();
-                       pending_events.push(MessageSendEvent::SendReplyChannelRange {
-                               node_id: their_node_id.clone(),
-                               msg: ReplyChannelRange {
-                                       chain_hash: msg.chain_hash.clone(),
-                                       first_blocknum: msg.first_blocknum,
-                                       number_of_blocks: msg.number_of_blocks,
-                                       sync_complete: true,
-                                       short_channel_ids: vec![],
-                               }
-                       });
-                       return Err(LightningError {
-                               err: String::from("query_channel_range could not be processed"),
-                               action: ErrorAction::IgnoreError,
-                       });
-               }
-
-               // Creates channel batches. We are not checking if the channel is routable
-               // (has at least one update). A peer may still want to know the channel
-               // exists even if its not yet routable.
-               let mut batches: Vec<Vec<u64>> = vec![Vec::with_capacity(MAX_SCIDS_PER_REPLY)];
-               let channels = self.network_graph.channels.read().unwrap();
-               for (_, ref chan) in channels.range(inclusive_start_scid.unwrap()..exclusive_end_scid.unwrap()) {
-                       if let Some(chan_announcement) = &chan.announcement_message {
-                               // Construct a new batch if last one is full
-                               if batches.last().unwrap().len() == batches.last().unwrap().capacity() {
-                                       batches.push(Vec::with_capacity(MAX_SCIDS_PER_REPLY));
-                               }
-
-                               let batch = batches.last_mut().unwrap();
-                               batch.push(chan_announcement.contents.short_channel_id);
-                       }
-               }
-               drop(channels);
-
-               let mut pending_events = self.pending_events.lock().unwrap();
-               let batch_count = batches.len();
-               let mut prev_batch_endblock = msg.first_blocknum;
-               for (batch_index, batch) in batches.into_iter().enumerate() {
-                       // Per spec, the initial `first_blocknum` needs to be <= the query's `first_blocknum`
-                       // and subsequent `first_blocknum`s must be >= the prior reply's `first_blocknum`.
-                       //
-                       // Additionally, c-lightning versions < 0.10 require that the `first_blocknum` of each
-                       // reply is >= the previous reply's `first_blocknum` and either exactly the previous
-                       // reply's `first_blocknum + number_of_blocks` or exactly one greater. This is a
-                       // significant diversion from the requirements set by the spec, and, in case of blocks
-                       // with no channel opens (e.g. empty blocks), requires that we use the previous value
-                       // and *not* derive the first_blocknum from the actual first block of the reply.
-                       let first_blocknum = prev_batch_endblock;
-
-                       // Each message carries the number of blocks (from the `first_blocknum`) its contents
-                       // fit in. Though there is no requirement that we use exactly the number of blocks its
-                       // contents are from, except for the bogus requirements c-lightning enforces, above.
-                       //
-                       // Per spec, the last end block (ie `first_blocknum + number_of_blocks`) needs to be
-                       // >= the query's end block. Thus, for the last reply, we calculate the difference
-                       // between the query's end block and the start of the reply.
-                       //
-                       // Overflow safe since end_blocknum=msg.first_block_num+msg.number_of_blocks and
-                       // first_blocknum will be either msg.first_blocknum or a higher block height.
-                       let (sync_complete, number_of_blocks) = if batch_index == batch_count-1 {
-                               (true, msg.end_blocknum() - first_blocknum)
-                       }
-                       // Prior replies should use the number of blocks that fit into the reply. Overflow
-                       // safe since first_blocknum is always <= last SCID's block.
-                       else {
-                               (false, block_from_scid(batch.last().unwrap()) - first_blocknum)
-                       };
-
-                       prev_batch_endblock = first_blocknum + number_of_blocks;
-
-                       pending_events.push(MessageSendEvent::SendReplyChannelRange {
-                               node_id: their_node_id.clone(),
-                               msg: ReplyChannelRange {
-                                       chain_hash: msg.chain_hash.clone(),
-                                       first_blocknum,
-                                       number_of_blocks,
-                                       sync_complete,
-                                       short_channel_ids: batch,
-                               }
-                       });
-               }
-
-               Ok(())
-       }
-
-       fn handle_query_short_channel_ids(&self, _their_node_id: &PublicKey, _msg: QueryShortChannelIds) -> Result<(), LightningError> {
-               // TODO
-               Err(LightningError {
-                       err: String::from("Not implemented"),
-                       action: ErrorAction::IgnoreError,
-               })
-       }
-}
-
-impl<G: Deref<Target=NetworkGraph>, C: Deref, L: Deref> MessageSendEventsProvider for P2PGossipSync<G, C, L>
-where
-       C::Target: chain::Access,
-       L::Target: Logger,
-{
-       fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
-               let mut ret = Vec::new();
-               let mut pending_events = self.pending_events.lock().unwrap();
-               core::mem::swap(&mut ret, &mut pending_events);
-               ret
-       }
-}
-
-#[derive(Clone, Debug, PartialEq)]
-/// Details about one direction of a channel as received within a [`ChannelUpdate`].
-pub struct ChannelUpdateInfo {
-       /// When the last update to the channel direction was issued.
-       /// Value is opaque, as set in the announcement.
-       pub last_update: u32,
-       /// Whether the channel can be currently used for payments (in this one direction).
-       pub enabled: bool,
-       /// The difference in CLTV values that you must have when routing through this channel.
-       pub cltv_expiry_delta: u16,
-       /// The minimum value, which must be relayed to the next hop via the channel
-       pub htlc_minimum_msat: u64,
-       /// The maximum value which may be relayed to the next hop via the channel.
-       pub htlc_maximum_msat: Option<u64>,
-       /// Fees charged when the channel is used for routing
-       pub fees: RoutingFees,
-       /// Most recent update for the channel received from the network
-       /// Mostly redundant with the data we store in fields explicitly.
-       /// Everything else is useful only for sending out for initial routing sync.
-       /// Not stored if contains excess data to prevent DoS.
-       pub last_update_message: Option<ChannelUpdate>,
-}
-
-impl fmt::Display for ChannelUpdateInfo {
-       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-               write!(f, "last_update {}, enabled {}, cltv_expiry_delta {}, htlc_minimum_msat {}, fees {:?}", self.last_update, self.enabled, self.cltv_expiry_delta, self.htlc_minimum_msat, self.fees)?;
-               Ok(())
-       }
-}
-
-impl_writeable_tlv_based!(ChannelUpdateInfo, {
-       (0, last_update, required),
-       (2, enabled, required),
-       (4, cltv_expiry_delta, required),
-       (6, htlc_minimum_msat, required),
-       (8, htlc_maximum_msat, required),
-       (10, fees, required),
-       (12, last_update_message, required),
-});
-
-#[derive(Clone, Debug, PartialEq)]
-/// Details about a channel (both directions).
-/// Received within a channel announcement.
-pub struct ChannelInfo {
-       /// Protocol features of a channel communicated during its announcement
-       pub features: ChannelFeatures,
-       /// Source node of the first direction of a channel
-       pub node_one: NodeId,
-       /// Details about the first direction of a channel
-       pub one_to_two: Option<ChannelUpdateInfo>,
-       /// Source node of the second direction of a channel
-       pub node_two: NodeId,
-       /// Details about the second direction of a channel
-       pub two_to_one: Option<ChannelUpdateInfo>,
-       /// The channel capacity as seen on-chain, if chain lookup is available.
-       pub capacity_sats: Option<u64>,
-       /// An initial announcement of the channel
-       /// Mostly redundant with the data we store in fields explicitly.
-       /// Everything else is useful only for sending out for initial routing sync.
-       /// Not stored if contains excess data to prevent DoS.
-       pub announcement_message: Option<ChannelAnnouncement>,
-       /// The timestamp when we received the announcement, if we are running with feature = "std"
-       /// (which we can probably assume we are - no-std environments probably won't have a full
-       /// network graph in memory!).
-       announcement_received_time: u64,
-}
-
-impl ChannelInfo {
-       /// Returns a [`DirectedChannelInfo`] for the channel directed to the given `target` from a
-       /// returned `source`, or `None` if `target` is not one of the channel's counterparties.
-       pub fn as_directed_to(&self, target: &NodeId) -> Option<(DirectedChannelInfo, &NodeId)> {
-               let (direction, source) = {
-                       if target == &self.node_one {
-                               (self.two_to_one.as_ref(), &self.node_two)
-                       } else if target == &self.node_two {
-                               (self.one_to_two.as_ref(), &self.node_one)
-                       } else {
-                               return None;
-                       }
-               };
-               Some((DirectedChannelInfo::new(self, direction), source))
-       }
-
-       /// Returns a [`DirectedChannelInfo`] for the channel directed from the given `source` to a
-       /// returned `target`, or `None` if `source` is not one of the channel's counterparties.
-       pub fn as_directed_from(&self, source: &NodeId) -> Option<(DirectedChannelInfo, &NodeId)> {
-               let (direction, target) = {
-                       if source == &self.node_one {
-                               (self.one_to_two.as_ref(), &self.node_two)
-                       } else if source == &self.node_two {
-                               (self.two_to_one.as_ref(), &self.node_one)
-                       } else {
-                               return None;
-                       }
-               };
-               Some((DirectedChannelInfo::new(self, direction), target))
-       }
-
-       /// Returns a [`ChannelUpdateInfo`] based on the direction implied by the channel_flag.
-       pub fn get_directional_info(&self, channel_flags: u8) -> Option<&ChannelUpdateInfo> {
-               let direction = channel_flags & 1u8;
-               if direction == 0 {
-                       self.one_to_two.as_ref()
-               } else {
-                       self.two_to_one.as_ref()
-               }
-       }
-}
-
-impl fmt::Display for ChannelInfo {
-       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-               write!(f, "features: {}, node_one: {}, one_to_two: {:?}, node_two: {}, two_to_one: {:?}",
-                  log_bytes!(self.features.encode()), log_bytes!(self.node_one.as_slice()), self.one_to_two, log_bytes!(self.node_two.as_slice()), self.two_to_one)?;
-               Ok(())
-       }
-}
-
-impl_writeable_tlv_based!(ChannelInfo, {
-       (0, features, required),
-       (1, announcement_received_time, (default_value, 0)),
-       (2, node_one, required),
-       (4, one_to_two, required),
-       (6, node_two, required),
-       (8, two_to_one, required),
-       (10, capacity_sats, required),
-       (12, announcement_message, required),
-});
-
-/// A wrapper around [`ChannelInfo`] representing information about the channel as directed from a
-/// source node to a target node.
-#[derive(Clone)]
-pub struct DirectedChannelInfo<'a> {
-       channel: &'a ChannelInfo,
-       direction: Option<&'a ChannelUpdateInfo>,
-       htlc_maximum_msat: u64,
-       effective_capacity: EffectiveCapacity,
-}
-
-impl<'a> DirectedChannelInfo<'a> {
-       #[inline]
-       fn new(channel: &'a ChannelInfo, direction: Option<&'a ChannelUpdateInfo>) -> Self {
-               let htlc_maximum_msat = direction.and_then(|direction| direction.htlc_maximum_msat);
-               let capacity_msat = channel.capacity_sats.map(|capacity_sats| capacity_sats * 1000);
-
-               let (htlc_maximum_msat, effective_capacity) = match (htlc_maximum_msat, capacity_msat) {
-                       (Some(amount_msat), Some(capacity_msat)) => {
-                               let htlc_maximum_msat = cmp::min(amount_msat, capacity_msat);
-                               (htlc_maximum_msat, EffectiveCapacity::Total { capacity_msat })
-                       },
-                       (Some(amount_msat), None) => {
-                               (amount_msat, EffectiveCapacity::MaximumHTLC { amount_msat })
-                       },
-                       (None, Some(capacity_msat)) => {
-                               (capacity_msat, EffectiveCapacity::Total { capacity_msat })
-                       },
-                       (None, None) => (EffectiveCapacity::Unknown.as_msat(), EffectiveCapacity::Unknown),
-               };
-
-               Self {
-                       channel, direction, htlc_maximum_msat, effective_capacity
-               }
-       }
-
-       /// Returns information for the channel.
-       pub fn channel(&self) -> &'a ChannelInfo { self.channel }
-
-       /// Returns information for the direction.
-       pub fn direction(&self) -> Option<&'a ChannelUpdateInfo> { self.direction }
-
-       /// Returns the maximum HTLC amount allowed over the channel in the direction.
-       pub fn htlc_maximum_msat(&self) -> u64 {
-               self.htlc_maximum_msat
-       }
-
-       /// Returns the [`EffectiveCapacity`] of the channel in the direction.
-       ///
-       /// This is either the total capacity from the funding transaction, if known, or the
-       /// `htlc_maximum_msat` for the direction as advertised by the gossip network, if known,
-       /// otherwise.
-       pub fn effective_capacity(&self) -> EffectiveCapacity {
-               self.effective_capacity
-       }
-
-       /// Returns `Some` if [`ChannelUpdateInfo`] is available in the direction.
-       pub(super) fn with_update(self) -> Option<DirectedChannelInfoWithUpdate<'a>> {
-               match self.direction {
-                       Some(_) => Some(DirectedChannelInfoWithUpdate { inner: self }),
-                       None => None,
-               }
-       }
-}
-
-impl<'a> fmt::Debug for DirectedChannelInfo<'a> {
-       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-               f.debug_struct("DirectedChannelInfo")
-                       .field("channel", &self.channel)
-                       .finish()
-       }
-}
-
-/// A [`DirectedChannelInfo`] with [`ChannelUpdateInfo`] available in its direction.
-#[derive(Clone)]
-pub(super) struct DirectedChannelInfoWithUpdate<'a> {
-       inner: DirectedChannelInfo<'a>,
-}
-
-impl<'a> DirectedChannelInfoWithUpdate<'a> {
-       /// Returns information for the channel.
-       #[inline]
-       pub(super) fn channel(&self) -> &'a ChannelInfo { &self.inner.channel }
-
-       /// Returns information for the direction.
-       #[inline]
-       pub(super) fn direction(&self) -> &'a ChannelUpdateInfo { self.inner.direction.unwrap() }
-
-       /// Returns the [`EffectiveCapacity`] of the channel in the direction.
-       #[inline]
-       pub(super) fn effective_capacity(&self) -> EffectiveCapacity { self.inner.effective_capacity() }
-
-       /// Returns the maximum HTLC amount allowed over the channel in the direction.
-       #[inline]
-       pub(super) fn htlc_maximum_msat(&self) -> u64 { self.inner.htlc_maximum_msat() }
-}
-
-impl<'a> fmt::Debug for DirectedChannelInfoWithUpdate<'a> {
-       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-               self.inner.fmt(f)
-       }
-}
-
-/// The effective capacity of a channel for routing purposes.
-///
-/// While this may be smaller than the actual channel capacity, amounts greater than
-/// [`Self::as_msat`] should not be routed through the channel.
-#[derive(Clone, Copy)]
-pub enum EffectiveCapacity {
-       /// The available liquidity in the channel known from being a channel counterparty, and thus a
-       /// direct hop.
-       ExactLiquidity {
-               /// Either the inbound or outbound liquidity depending on the direction, denominated in
-               /// millisatoshi.
-               liquidity_msat: u64,
-       },
-       /// The maximum HTLC amount in one direction as advertised on the gossip network.
-       MaximumHTLC {
-               /// The maximum HTLC amount denominated in millisatoshi.
-               amount_msat: u64,
-       },
-       /// The total capacity of the channel as determined by the funding transaction.
-       Total {
-               /// The funding amount denominated in millisatoshi.
-               capacity_msat: u64,
-       },
-       /// A capacity sufficient to route any payment, typically used for private channels provided by
-       /// an invoice.
-       Infinite,
-       /// A capacity that is unknown possibly because either the chain state is unavailable to know
-       /// the total capacity or the `htlc_maximum_msat` was not advertised on the gossip network.
-       Unknown,
-}
-
-/// The presumed channel capacity denominated in millisatoshi for [`EffectiveCapacity::Unknown`] to
-/// use when making routing decisions.
-pub const UNKNOWN_CHANNEL_CAPACITY_MSAT: u64 = 250_000 * 1000;
-
-impl EffectiveCapacity {
-       /// Returns the effective capacity denominated in millisatoshi.
-       pub fn as_msat(&self) -> u64 {
-               match self {
-                       EffectiveCapacity::ExactLiquidity { liquidity_msat } => *liquidity_msat,
-                       EffectiveCapacity::MaximumHTLC { amount_msat } => *amount_msat,
-                       EffectiveCapacity::Total { capacity_msat } => *capacity_msat,
-                       EffectiveCapacity::Infinite => u64::max_value(),
-                       EffectiveCapacity::Unknown => UNKNOWN_CHANNEL_CAPACITY_MSAT,
-               }
-       }
-}
-
-/// Fees for routing via a given channel or a node
-#[derive(Eq, PartialEq, Copy, Clone, Debug, Hash)]
-pub struct RoutingFees {
-       /// Flat routing fee in satoshis
-       pub base_msat: u32,
-       /// Liquidity-based routing fee in millionths of a routed amount.
-       /// In other words, 10000 is 1%.
-       pub proportional_millionths: u32,
-}
-
-impl_writeable_tlv_based!(RoutingFees, {
-       (0, base_msat, required),
-       (2, proportional_millionths, required)
-});
-
-#[derive(Clone, Debug, PartialEq)]
-/// Information received in the latest node_announcement from this node.
-pub struct NodeAnnouncementInfo {
-       /// Protocol features the node announced support for
-       pub features: NodeFeatures,
-       /// When the last known update to the node state was issued.
-       /// Value is opaque, as set in the announcement.
-       pub last_update: u32,
-       /// Color assigned to the node
-       pub rgb: [u8; 3],
-       /// Moniker assigned to the node.
-       /// May be invalid or malicious (eg control chars),
-       /// should not be exposed to the user.
-       pub alias: [u8; 32],
-       /// Internet-level addresses via which one can connect to the node
-       pub addresses: Vec<NetAddress>,
-       /// An initial announcement of the node
-       /// Mostly redundant with the data we store in fields explicitly.
-       /// Everything else is useful only for sending out for initial routing sync.
-       /// Not stored if contains excess data to prevent DoS.
-       pub announcement_message: Option<NodeAnnouncement>
-}
-
-impl_writeable_tlv_based!(NodeAnnouncementInfo, {
-       (0, features, required),
-       (2, last_update, required),
-       (4, rgb, required),
-       (6, alias, required),
-       (8, announcement_message, option),
-       (10, addresses, vec_type),
-});
-
-#[derive(Clone, Debug, PartialEq)]
-/// Details about a node in the network, known from the network announcement.
-pub struct NodeInfo {
-       /// All valid channels a node has announced
-       pub channels: Vec<u64>,
-       /// Lowest fees enabling routing via any of the enabled, known channels to a node.
-       /// The two fields (flat and proportional fee) are independent,
-       /// meaning they don't have to refer to the same channel.
-       pub lowest_inbound_channel_fees: Option<RoutingFees>,
-       /// More information about a node from node_announcement.
-       /// Optional because we store a Node entry after learning about it from
-       /// a channel announcement, but before receiving a node announcement.
-       pub announcement_info: Option<NodeAnnouncementInfo>
-}
-
-impl fmt::Display for NodeInfo {
-       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-               write!(f, "lowest_inbound_channel_fees: {:?}, channels: {:?}, announcement_info: {:?}",
-                  self.lowest_inbound_channel_fees, &self.channels[..], self.announcement_info)?;
-               Ok(())
-       }
-}
-
-impl_writeable_tlv_based!(NodeInfo, {
-       (0, lowest_inbound_channel_fees, option),
-       (2, announcement_info, option),
-       (4, channels, vec_type),
-});
-
-const SERIALIZATION_VERSION: u8 = 1;
-const MIN_SERIALIZATION_VERSION: u8 = 1;
-
-impl Writeable for NetworkGraph {
-       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
-               write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
-
-               self.genesis_hash.write(writer)?;
-               let channels = self.channels.read().unwrap();
-               (channels.len() as u64).write(writer)?;
-               for (ref chan_id, ref chan_info) in channels.iter() {
-                       (*chan_id).write(writer)?;
-                       chan_info.write(writer)?;
-               }
-               let nodes = self.nodes.read().unwrap();
-               (nodes.len() as u64).write(writer)?;
-               for (ref node_id, ref node_info) in nodes.iter() {
-                       node_id.write(writer)?;
-                       node_info.write(writer)?;
-               }
-
-               let last_rapid_gossip_sync_timestamp = self.get_last_rapid_gossip_sync_timestamp();
-               write_tlv_fields!(writer, {
-                       (1, last_rapid_gossip_sync_timestamp, option),
-               });
-               Ok(())
-       }
-}
-
-impl Readable for NetworkGraph {
-       fn read<R: io::Read>(reader: &mut R) -> Result<NetworkGraph, DecodeError> {
-               let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
-
-               let genesis_hash: BlockHash = Readable::read(reader)?;
-               let channels_count: u64 = Readable::read(reader)?;
-               let mut channels = BTreeMap::new();
-               for _ in 0..channels_count {
-                       let chan_id: u64 = Readable::read(reader)?;
-                       let chan_info = Readable::read(reader)?;
-                       channels.insert(chan_id, chan_info);
-               }
-               let nodes_count: u64 = Readable::read(reader)?;
-               let mut nodes = BTreeMap::new();
-               for _ in 0..nodes_count {
-                       let node_id = Readable::read(reader)?;
-                       let node_info = Readable::read(reader)?;
-                       nodes.insert(node_id, node_info);
-               }
-
-               let mut last_rapid_gossip_sync_timestamp: Option<u32> = None;
-               read_tlv_fields!(reader, {
-                       (1, last_rapid_gossip_sync_timestamp, option),
-               });
-
-               Ok(NetworkGraph {
-                       genesis_hash,
-                       channels: RwLock::new(channels),
-                       nodes: RwLock::new(nodes),
-                       last_rapid_gossip_sync_timestamp: Mutex::new(last_rapid_gossip_sync_timestamp),
-               })
-       }
-}
-
-impl fmt::Display for NetworkGraph {
-       fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-               writeln!(f, "Network map\n[Channels]")?;
-               for (key, val) in self.channels.read().unwrap().iter() {
-                       writeln!(f, " {}: {}", key, val)?;
-               }
-               writeln!(f, "[Nodes]")?;
-               for (&node_id, val) in self.nodes.read().unwrap().iter() {
-                       writeln!(f, " {}: {}", log_bytes!(node_id.as_slice()), val)?;
-               }
-               Ok(())
-       }
-}
-
-impl PartialEq for NetworkGraph {
-       fn eq(&self, other: &Self) -> bool {
-               self.genesis_hash == other.genesis_hash &&
-                       *self.channels.read().unwrap() == *other.channels.read().unwrap() &&
-                       *self.nodes.read().unwrap() == *other.nodes.read().unwrap()
-       }
-}
-
-impl NetworkGraph {
-       /// Creates a new, empty, network graph.
-       pub fn new(genesis_hash: BlockHash) -> NetworkGraph {
-               Self {
-                       genesis_hash,
-                       channels: RwLock::new(BTreeMap::new()),
-                       nodes: RwLock::new(BTreeMap::new()),
-                       last_rapid_gossip_sync_timestamp: Mutex::new(None),
-               }
-       }
-
-       /// Returns a read-only view of the network graph.
-       pub fn read_only(&'_ self) -> ReadOnlyNetworkGraph<'_> {
-               let channels = self.channels.read().unwrap();
-               let nodes = self.nodes.read().unwrap();
-               ReadOnlyNetworkGraph {
-                       channels,
-                       nodes,
-               }
-       }
-
-       /// The unix timestamp provided by the most recent rapid gossip sync.
-       /// It will be set by the rapid sync process after every sync completion.
-       pub fn get_last_rapid_gossip_sync_timestamp(&self) -> Option<u32> {
-               self.last_rapid_gossip_sync_timestamp.lock().unwrap().clone()
-       }
-
-       /// Update the unix timestamp provided by the most recent rapid gossip sync.
-       /// This should be done automatically by the rapid sync process after every sync completion.
-       pub fn set_last_rapid_gossip_sync_timestamp(&self, last_rapid_gossip_sync_timestamp: u32) {
-               self.last_rapid_gossip_sync_timestamp.lock().unwrap().replace(last_rapid_gossip_sync_timestamp);
-       }
-
-       /// Clears the `NodeAnnouncementInfo` field for all nodes in the `NetworkGraph` for testing
-       /// purposes.
-       #[cfg(test)]
-       pub fn clear_nodes_announcement_info(&self) {
-               for node in self.nodes.write().unwrap().iter_mut() {
-                       node.1.announcement_info = None;
-               }
-       }
-
-       /// For an already known node (from channel announcements), update its stored properties from a
-       /// given node announcement.
-       ///
-       /// You probably don't want to call this directly, instead relying on a P2PGossipSync's
-       /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
-       /// routing messages from a source using a protocol other than the lightning P2P protocol.
-       pub fn update_node_from_announcement<T: secp256k1::Verification>(&self, msg: &msgs::NodeAnnouncement, secp_ctx: &Secp256k1<T>) -> Result<(), LightningError> {
-               let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
-               secp_verify_sig!(secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id, "node_announcement");
-               self.update_node_from_announcement_intern(&msg.contents, Some(&msg))
-       }
-
-       /// For an already known node (from channel announcements), update its stored properties from a
-       /// given node announcement without verifying the associated signatures. Because we aren't
-       /// given the associated signatures here we cannot relay the node announcement to any of our
-       /// peers.
-       pub fn update_node_from_unsigned_announcement(&self, msg: &msgs::UnsignedNodeAnnouncement) -> Result<(), LightningError> {
-               self.update_node_from_announcement_intern(msg, None)
-       }
-
-       fn update_node_from_announcement_intern(&self, msg: &msgs::UnsignedNodeAnnouncement, full_msg: Option<&msgs::NodeAnnouncement>) -> Result<(), LightningError> {
-               match self.nodes.write().unwrap().get_mut(&NodeId::from_pubkey(&msg.node_id)) {
-                       None => Err(LightningError{err: "No existing channels for node_announcement".to_owned(), action: ErrorAction::IgnoreError}),
-                       Some(node) => {
-                               if let Some(node_info) = node.announcement_info.as_ref() {
-                                       // The timestamp field is somewhat of a misnomer - the BOLTs use it to order
-                                       // updates to ensure you always have the latest one, only vaguely suggesting
-                                       // that it be at least the current time.
-                                       if node_info.last_update  > msg.timestamp {
-                                               return Err(LightningError{err: "Update older than last processed update".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
-                                       } else if node_info.last_update  == msg.timestamp {
-                                               return Err(LightningError{err: "Update had the same timestamp as last processed update".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
-                                       }
-                               }
-
-                               let should_relay =
-                                       msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY &&
-                                       msg.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY &&
-                                       msg.excess_data.len() + msg.excess_address_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY;
-                               node.announcement_info = Some(NodeAnnouncementInfo {
-                                       features: msg.features.clone(),
-                                       last_update: msg.timestamp,
-                                       rgb: msg.rgb,
-                                       alias: msg.alias,
-                                       addresses: msg.addresses.clone(),
-                                       announcement_message: if should_relay { full_msg.cloned() } else { None },
-                               });
-
-                               Ok(())
-                       }
-               }
-       }
-
-       /// Store or update channel info from a channel announcement.
-       ///
-       /// You probably don't want to call this directly, instead relying on a P2PGossipSync's
-       /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
-       /// routing messages from a source using a protocol other than the lightning P2P protocol.
-       ///
-       /// If a `chain::Access` object is provided via `chain_access`, it will be called to verify
-       /// the corresponding UTXO exists on chain and is correctly-formatted.
-       pub fn update_channel_from_announcement<T: secp256k1::Verification, C: Deref>(
-               &self, msg: &msgs::ChannelAnnouncement, chain_access: &Option<C>, secp_ctx: &Secp256k1<T>
-       ) -> Result<(), LightningError>
-       where
-               C::Target: chain::Access,
-       {
-               let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
-               secp_verify_sig!(secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1, "channel_announcement");
-               secp_verify_sig!(secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2, "channel_announcement");
-               secp_verify_sig!(secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1, "channel_announcement");
-               secp_verify_sig!(secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2, "channel_announcement");
-               self.update_channel_from_unsigned_announcement_intern(&msg.contents, Some(msg), chain_access)
-       }
-
-       /// Store or update channel info from a channel announcement without verifying the associated
-       /// signatures. Because we aren't given the associated signatures here we cannot relay the
-       /// channel announcement to any of our peers.
-       ///
-       /// If a `chain::Access` object is provided via `chain_access`, it will be called to verify
-       /// the corresponding UTXO exists on chain and is correctly-formatted.
-       pub fn update_channel_from_unsigned_announcement<C: Deref>(
-               &self, msg: &msgs::UnsignedChannelAnnouncement, chain_access: &Option<C>
-       ) -> Result<(), LightningError>
-       where
-               C::Target: chain::Access,
-       {
-               self.update_channel_from_unsigned_announcement_intern(msg, None, chain_access)
-       }
-
-       /// Update channel from partial announcement data received via rapid gossip sync
-       ///
-       /// `timestamp: u64`: Timestamp emulating the backdated original announcement receipt (by the
-       /// rapid gossip sync server)
-       ///
-       /// All other parameters as used in [`msgs::UnsignedChannelAnnouncement`] fields.
-       pub fn add_channel_from_partial_announcement(&self, short_channel_id: u64, timestamp: u64, features: ChannelFeatures, node_id_1: PublicKey, node_id_2: PublicKey) -> Result<(), LightningError> {
-               if node_id_1 == node_id_2 {
-                       return Err(LightningError{err: "Channel announcement node had a channel with itself".to_owned(), action: ErrorAction::IgnoreError});
-               };
-
-               let node_1 = NodeId::from_pubkey(&node_id_1);
-               let node_2 = NodeId::from_pubkey(&node_id_2);
-               let channel_info = ChannelInfo {
-                       features,
-                       node_one: node_1.clone(),
-                       one_to_two: None,
-                       node_two: node_2.clone(),
-                       two_to_one: None,
-                       capacity_sats: None,
-                       announcement_message: None,
-                       announcement_received_time: timestamp,
-               };
-
-               self.add_channel_between_nodes(short_channel_id, channel_info, None)
-       }
-
-       fn add_channel_between_nodes(&self, short_channel_id: u64, channel_info: ChannelInfo, utxo_value: Option<u64>) -> Result<(), LightningError> {
-               let mut channels = self.channels.write().unwrap();
-               let mut nodes = self.nodes.write().unwrap();
-
-               let node_id_a = channel_info.node_one.clone();
-               let node_id_b = channel_info.node_two.clone();
-
-               match channels.entry(short_channel_id) {
-                       BtreeEntry::Occupied(mut entry) => {
-                               //TODO: because asking the blockchain if short_channel_id is valid is only optional
-                               //in the blockchain API, we need to handle it smartly here, though it's unclear
-                               //exactly how...
-                               if utxo_value.is_some() {
-                                       // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
-                                       // only sometimes returns results. In any case remove the previous entry. Note
-                                       // that the spec expects us to "blacklist" the node_ids involved, but we can't
-                                       // do that because
-                                       // a) we don't *require* a UTXO provider that always returns results.
-                                       // b) we don't track UTXOs of channels we know about and remove them if they
-                                       //    get reorg'd out.
-                                       // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
-                                       Self::remove_channel_in_nodes(&mut nodes, &entry.get(), short_channel_id);
-                                       *entry.get_mut() = channel_info;
-                               } else {
-                                       return Err(LightningError{err: "Already have knowledge of channel".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
-                               }
-                       },
-                       BtreeEntry::Vacant(entry) => {
-                               entry.insert(channel_info);
-                       }
-               };
-
-               for current_node_id in [node_id_a, node_id_b].iter() {
-                       match nodes.entry(current_node_id.clone()) {
-                               BtreeEntry::Occupied(node_entry) => {
-                                       node_entry.into_mut().channels.push(short_channel_id);
-                               },
-                               BtreeEntry::Vacant(node_entry) => {
-                                       node_entry.insert(NodeInfo {
-                                               channels: vec!(short_channel_id),
-                                               lowest_inbound_channel_fees: None,
-                                               announcement_info: None,
-                                       });
-                               }
-                       };
-               };
-
-               Ok(())
-       }
-
-       fn update_channel_from_unsigned_announcement_intern<C: Deref>(
-               &self, msg: &msgs::UnsignedChannelAnnouncement, full_msg: Option<&msgs::ChannelAnnouncement>, chain_access: &Option<C>
-       ) -> Result<(), LightningError>
-       where
-               C::Target: chain::Access,
-       {
-               if msg.node_id_1 == msg.node_id_2 || msg.bitcoin_key_1 == msg.bitcoin_key_2 {
-                       return Err(LightningError{err: "Channel announcement node had a channel with itself".to_owned(), action: ErrorAction::IgnoreError});
-               }
-
-               let utxo_value = match &chain_access {
-                       &None => {
-                               // Tentatively accept, potentially exposing us to DoS attacks
-                               None
-                       },
-                       &Some(ref chain_access) => {
-                               match chain_access.get_utxo(&msg.chain_hash, msg.short_channel_id) {
-                                       Ok(TxOut { value, script_pubkey }) => {
-                                               let expected_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
-                                                                                   .push_slice(&msg.bitcoin_key_1.serialize())
-                                                                                   .push_slice(&msg.bitcoin_key_2.serialize())
-                                                                                   .push_opcode(opcodes::all::OP_PUSHNUM_2)
-                                                                                   .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
-                                               if script_pubkey != expected_script {
-                                                       return Err(LightningError{err: format!("Channel announcement key ({}) didn't match on-chain script ({})", script_pubkey.to_hex(), expected_script.to_hex()), action: ErrorAction::IgnoreError});
-                                               }
-                                               //TODO: Check if value is worth storing, use it to inform routing, and compare it
-                                               //to the new HTLC max field in channel_update
-                                               Some(value)
-                                       },
-                                       Err(chain::AccessError::UnknownChain) => {
-                                               return Err(LightningError{err: format!("Channel announced on an unknown chain ({})", msg.chain_hash.encode().to_hex()), action: ErrorAction::IgnoreError});
-                                       },
-                                       Err(chain::AccessError::UnknownTx) => {
-                                               return Err(LightningError{err: "Channel announced without corresponding UTXO entry".to_owned(), action: ErrorAction::IgnoreError});
-                                       },
-                               }
-                       },
-               };
-
-               #[allow(unused_mut, unused_assignments)]
-               let mut announcement_received_time = 0;
-               #[cfg(feature = "std")]
-               {
-                       announcement_received_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
-               }
-
-               let chan_info = ChannelInfo {
-                       features: msg.features.clone(),
-                       node_one: NodeId::from_pubkey(&msg.node_id_1),
-                       one_to_two: None,
-                       node_two: NodeId::from_pubkey(&msg.node_id_2),
-                       two_to_one: None,
-                       capacity_sats: utxo_value,
-                       announcement_message: if msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY
-                               { full_msg.cloned() } else { None },
-                       announcement_received_time,
-               };
-
-               self.add_channel_between_nodes(msg.short_channel_id, chan_info, utxo_value)
-       }
-
-       /// Marks a channel in the graph as failed if a corresponding HTLC fail was sent.
-       /// If permanent, removes a channel from the local storage.
-       /// May cause the removal of nodes too, if this was their last channel.
-       /// If not permanent, makes channels unavailable for routing.
-       pub fn channel_failed(&self, short_channel_id: u64, is_permanent: bool) {
-               let mut channels = self.channels.write().unwrap();
-               if is_permanent {
-                       if let Some(chan) = channels.remove(&short_channel_id) {
-                               let mut nodes = self.nodes.write().unwrap();
-                               Self::remove_channel_in_nodes(&mut nodes, &chan, short_channel_id);
-                       }
-               } else {
-                       if let Some(chan) = channels.get_mut(&short_channel_id) {
-                               if let Some(one_to_two) = chan.one_to_two.as_mut() {
-                                       one_to_two.enabled = false;
-                               }
-                               if let Some(two_to_one) = chan.two_to_one.as_mut() {
-                                       two_to_one.enabled = false;
-                               }
-                       }
-               }
-       }
-
-       /// Marks a node in the graph as failed.
-       pub fn node_failed(&self, _node_id: &PublicKey, is_permanent: bool) {
-               if is_permanent {
-                       // TODO: Wholly remove the node
-               } else {
-                       // TODO: downgrade the node
-               }
-       }
-
-       #[cfg(feature = "std")]
-       /// Removes information about channels that we haven't heard any updates about in some time.
-       /// This can be used regularly to prune the network graph of channels that likely no longer
-       /// exist.
-       ///
-       /// While there is no formal requirement that nodes regularly re-broadcast their channel
-       /// updates every two weeks, the non-normative section of BOLT 7 currently suggests that
-       /// pruning occur for updates which are at least two weeks old, which we implement here.
-       ///
-       /// Note that for users of the `lightning-background-processor` crate this method may be
-       /// automatically called regularly for you.
-       ///
-       /// This method is only available with the `std` feature. See
-       /// [`NetworkGraph::remove_stale_channels_with_time`] for `no-std` use.
-       pub fn remove_stale_channels(&self) {
-               let time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
-               self.remove_stale_channels_with_time(time);
-       }
-
-       /// Removes information about channels that we haven't heard any updates about in some time.
-       /// This can be used regularly to prune the network graph of channels that likely no longer
-       /// exist.
-       ///
-       /// While there is no formal requirement that nodes regularly re-broadcast their channel
-       /// updates every two weeks, the non-normative section of BOLT 7 currently suggests that
-       /// pruning occur for updates which are at least two weeks old, which we implement here.
-       ///
-       /// This function takes the current unix time as an argument. For users with the `std` feature
-       /// enabled, [`NetworkGraph::remove_stale_channels`] may be preferable.
-       pub fn remove_stale_channels_with_time(&self, current_time_unix: u64) {
-               let mut channels = self.channels.write().unwrap();
-               // Time out if we haven't received an update in at least 14 days.
-               if current_time_unix > u32::max_value() as u64 { return; } // Remove by 2106
-               if current_time_unix < STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS { return; }
-               let min_time_unix: u32 = (current_time_unix - STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS) as u32;
-               // Sadly BTreeMap::retain was only stabilized in 1.53 so we can't switch to it for some
-               // time.
-               let mut scids_to_remove = Vec::new();
-               for (scid, info) in channels.iter_mut() {
-                       if info.one_to_two.is_some() && info.one_to_two.as_ref().unwrap().last_update < min_time_unix {
-                               info.one_to_two = None;
-                       }
-                       if info.two_to_one.is_some() && info.two_to_one.as_ref().unwrap().last_update < min_time_unix {
-                               info.two_to_one = None;
-                       }
-                       if info.one_to_two.is_none() && info.two_to_one.is_none() {
-                               // We check the announcement_received_time here to ensure we don't drop
-                               // announcements that we just received and are just waiting for our peer to send a
-                               // channel_update for.
-                               if info.announcement_received_time < min_time_unix as u64 {
-                                       scids_to_remove.push(*scid);
-                               }
-                       }
-               }
-               if !scids_to_remove.is_empty() {
-                       let mut nodes = self.nodes.write().unwrap();
-                       for scid in scids_to_remove {
-                               let info = channels.remove(&scid).expect("We just accessed this scid, it should be present");
-                               Self::remove_channel_in_nodes(&mut nodes, &info, scid);
-                       }
-               }
-       }
-
-       /// For an already known (from announcement) channel, update info about one of the directions
-       /// of the channel.
-       ///
-       /// You probably don't want to call this directly, instead relying on a P2PGossipSync's
-       /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
-       /// routing messages from a source using a protocol other than the lightning P2P protocol.
-       ///
-       /// If built with `no-std`, any updates with a timestamp more than two weeks in the past or
-       /// materially in the future will be rejected.
-       pub fn update_channel<T: secp256k1::Verification>(&self, msg: &msgs::ChannelUpdate, secp_ctx: &Secp256k1<T>) -> Result<(), LightningError> {
-               self.update_channel_intern(&msg.contents, Some(&msg), Some((&msg.signature, secp_ctx)))
-       }
-
-       /// For an already known (from announcement) channel, update info about one of the directions
-       /// of the channel without verifying the associated signatures. Because we aren't given the
-       /// associated signatures here we cannot relay the channel update to any of our peers.
-       ///
-       /// If built with `no-std`, any updates with a timestamp more than two weeks in the past or
-       /// materially in the future will be rejected.
-       pub fn update_channel_unsigned(&self, msg: &msgs::UnsignedChannelUpdate) -> Result<(), LightningError> {
-               self.update_channel_intern(msg, None, None::<(&secp256k1::ecdsa::Signature, &Secp256k1<secp256k1::VerifyOnly>)>)
-       }
-
-       fn update_channel_intern<T: secp256k1::Verification>(&self, msg: &msgs::UnsignedChannelUpdate, full_msg: Option<&msgs::ChannelUpdate>, sig_info: Option<(&secp256k1::ecdsa::Signature, &Secp256k1<T>)>) -> Result<(), LightningError> {
-               let dest_node_id;
-               let chan_enabled = msg.flags & (1 << 1) != (1 << 1);
-               let chan_was_enabled;
-
-               #[cfg(all(feature = "std", not(test), not(feature = "_test_utils")))]
-               {
-                       // Note that many tests rely on being able to set arbitrarily old timestamps, thus we
-                       // disable this check during tests!
-                       let time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
-                       if (msg.timestamp as u64) < time - STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS {
-                               return Err(LightningError{err: "channel_update is older than two weeks old".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
-                       }
-                       if msg.timestamp as u64 > time + 60 * 60 * 24 {
-                               return Err(LightningError{err: "channel_update has a timestamp more than a day in the future".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
-                       }
-               }
-
-               let mut channels = self.channels.write().unwrap();
-               match channels.get_mut(&msg.short_channel_id) {
-                       None => return Err(LightningError{err: "Couldn't find channel for update".to_owned(), action: ErrorAction::IgnoreError}),
-                       Some(channel) => {
-                               if let OptionalField::Present(htlc_maximum_msat) = msg.htlc_maximum_msat {
-                                       if htlc_maximum_msat > MAX_VALUE_MSAT {
-                                               return Err(LightningError{err: "htlc_maximum_msat is larger than maximum possible msats".to_owned(), action: ErrorAction::IgnoreError});
-                                       }
-
-                                       if let Some(capacity_sats) = channel.capacity_sats {
-                                               // It's possible channel capacity is available now, although it wasn't available at announcement (so the field is None).
-                                               // Don't query UTXO set here to reduce DoS risks.
-                                               if capacity_sats > MAX_VALUE_MSAT / 1000 || htlc_maximum_msat > capacity_sats * 1000 {
-                                                       return Err(LightningError{err: "htlc_maximum_msat is larger than channel capacity or capacity is bogus".to_owned(), action: ErrorAction::IgnoreError});
-                                               }
-                                       }
-                               }
-                               macro_rules! check_update_latest {
-                                       ($target: expr) => {
-                                               if let Some(existing_chan_info) = $target.as_ref() {
-                                                       // The timestamp field is somewhat of a misnomer - the BOLTs use it to
-                                                       // order updates to ensure you always have the latest one, only
-                                                       // suggesting  that it be at least the current time. For
-                                                       // channel_updates specifically, the BOLTs discuss the possibility of
-                                                       // pruning based on the timestamp field being more than two weeks old,
-                                                       // but only in the non-normative section.
-                                                       if existing_chan_info.last_update > msg.timestamp {
-                                                               return Err(LightningError{err: "Update older than last processed update".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
-                                                       } else if existing_chan_info.last_update == msg.timestamp {
-                                                               return Err(LightningError{err: "Update had same timestamp as last processed update".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
-                                                       }
-                                                       chan_was_enabled = existing_chan_info.enabled;
-                                               } else {
-                                                       chan_was_enabled = false;
-                                               }
-                                       }
-                               }
-
-                               macro_rules! get_new_channel_info {
-                                       () => { {
-                                               let last_update_message = if msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY
-                                                       { full_msg.cloned() } else { None };
-
-                                               let updated_channel_update_info = ChannelUpdateInfo {
-                                                       enabled: chan_enabled,
-                                                       last_update: msg.timestamp,
-                                                       cltv_expiry_delta: msg.cltv_expiry_delta,
-                                                       htlc_minimum_msat: msg.htlc_minimum_msat,
-                                                       htlc_maximum_msat: if let OptionalField::Present(max_value) = msg.htlc_maximum_msat { Some(max_value) } else { None },
-                                                       fees: RoutingFees {
-                                                               base_msat: msg.fee_base_msat,
-                                                               proportional_millionths: msg.fee_proportional_millionths,
-                                                       },
-                                                       last_update_message
-                                               };
-                                               Some(updated_channel_update_info)
-                                       } }
-                               }
-
-                               let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
-                               if msg.flags & 1 == 1 {
-                                       dest_node_id = channel.node_one.clone();
-                                       check_update_latest!(channel.two_to_one);
-                                       if let Some((sig, ctx)) = sig_info {
-                                               secp_verify_sig!(ctx, &msg_hash, &sig, &PublicKey::from_slice(channel.node_two.as_slice()).map_err(|_| LightningError{
-                                                       err: "Couldn't parse source node pubkey".to_owned(),
-                                                       action: ErrorAction::IgnoreAndLog(Level::Debug)
-                                               })?, "channel_update");
-                                       }
-                                       channel.two_to_one = get_new_channel_info!();
-                               } else {
-                                       dest_node_id = channel.node_two.clone();
-                                       check_update_latest!(channel.one_to_two);
-                                       if let Some((sig, ctx)) = sig_info {
-                                               secp_verify_sig!(ctx, &msg_hash, &sig, &PublicKey::from_slice(channel.node_one.as_slice()).map_err(|_| LightningError{
-                                                       err: "Couldn't parse destination node pubkey".to_owned(),
-                                                       action: ErrorAction::IgnoreAndLog(Level::Debug)
-                                               })?, "channel_update");
-                                       }
-                                       channel.one_to_two = get_new_channel_info!();
-                               }
-                       }
-               }
-
-               let mut nodes = self.nodes.write().unwrap();
-               if chan_enabled {
-                       let node = nodes.get_mut(&dest_node_id).unwrap();
-                       let mut base_msat = msg.fee_base_msat;
-                       let mut proportional_millionths = msg.fee_proportional_millionths;
-                       if let Some(fees) = node.lowest_inbound_channel_fees {
-                               base_msat = cmp::min(base_msat, fees.base_msat);
-                               proportional_millionths = cmp::min(proportional_millionths, fees.proportional_millionths);
-                       }
-                       node.lowest_inbound_channel_fees = Some(RoutingFees {
-                               base_msat,
-                               proportional_millionths
-                       });
-               } else if chan_was_enabled {
-                       let node = nodes.get_mut(&dest_node_id).unwrap();
-                       let mut lowest_inbound_channel_fees = None;
-
-                       for chan_id in node.channels.iter() {
-                               let chan = channels.get(chan_id).unwrap();
-                               let chan_info_opt;
-                               if chan.node_one == dest_node_id {
-                                       chan_info_opt = chan.two_to_one.as_ref();
-                               } else {
-                                       chan_info_opt = chan.one_to_two.as_ref();
-                               }
-                               if let Some(chan_info) = chan_info_opt {
-                                       if chan_info.enabled {
-                                               let fees = lowest_inbound_channel_fees.get_or_insert(RoutingFees {
-                                                       base_msat: u32::max_value(), proportional_millionths: u32::max_value() });
-                                               fees.base_msat = cmp::min(fees.base_msat, chan_info.fees.base_msat);
-                                               fees.proportional_millionths = cmp::min(fees.proportional_millionths, chan_info.fees.proportional_millionths);
-                                       }
-                               }
-                       }
-
-                       node.lowest_inbound_channel_fees = lowest_inbound_channel_fees;
-               }
-
-               Ok(())
-       }
-
-       fn remove_channel_in_nodes(nodes: &mut BTreeMap<NodeId, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
-               macro_rules! remove_from_node {
-                       ($node_id: expr) => {
-                               if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
-                                       entry.get_mut().channels.retain(|chan_id| {
-                                               short_channel_id != *chan_id
-                                       });
-                                       if entry.get().channels.is_empty() {
-                                               entry.remove_entry();
-                                       }
-                               } else {
-                                       panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
-                               }
-                       }
-               }
-
-               remove_from_node!(chan.node_one);
-               remove_from_node!(chan.node_two);
-       }
-}
-
-impl ReadOnlyNetworkGraph<'_> {
-       /// Returns all known valid channels' short ids along with announced channel info.
-       ///
-       /// (C-not exported) because we have no mapping for `BTreeMap`s
-       pub fn channels(&self) -> &BTreeMap<u64, ChannelInfo> {
-               &*self.channels
-       }
-
-       /// Returns all known nodes' public keys along with announced node info.
-       ///
-       /// (C-not exported) because we have no mapping for `BTreeMap`s
-       pub fn nodes(&self) -> &BTreeMap<NodeId, NodeInfo> {
-               &*self.nodes
-       }
-
-       /// Get network addresses by node id.
-       /// Returns None if the requested node is completely unknown,
-       /// or if node announcement for the node was never received.
-       pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
-               if let Some(node) = self.nodes.get(&NodeId::from_pubkey(&pubkey)) {
-                       if let Some(node_info) = node.announcement_info.as_ref() {
-                               return Some(node_info.addresses.clone())
-                       }
-               }
-               None
-       }
-}
-
-#[cfg(test)]
-mod tests {
-       use chain;
-       use ln::PaymentHash;
-       use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
-       use routing::network_graph::{P2PGossipSync, NetworkGraph, NetworkUpdate, MAX_EXCESS_BYTES_FOR_RELAY};
-       use ln::msgs::{Init, OptionalField, RoutingMessageHandler, UnsignedNodeAnnouncement, NodeAnnouncement,
-               UnsignedChannelAnnouncement, ChannelAnnouncement, UnsignedChannelUpdate, ChannelUpdate,
-               ReplyChannelRange, QueryChannelRange, QueryShortChannelIds, MAX_VALUE_MSAT};
-       use util::test_utils;
-       use util::logger::Logger;
-       use util::ser::{Readable, Writeable};
-       use util::events::{Event, EventHandler, MessageSendEvent, MessageSendEventsProvider};
-       use util::scid_utils::scid_from_parts;
-
-       use super::STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS;
-
-       use bitcoin::hashes::sha256d::Hash as Sha256dHash;
-       use bitcoin::hashes::Hash;
-       use bitcoin::network::constants::Network;
-       use bitcoin::blockdata::constants::genesis_block;
-       use bitcoin::blockdata::script::{Builder, Script};
-       use bitcoin::blockdata::transaction::TxOut;
-       use bitcoin::blockdata::opcodes;
-
-       use hex;
-
-       use bitcoin::secp256k1::{PublicKey, SecretKey};
-       use bitcoin::secp256k1::{All, Secp256k1};
-
-       use io;
-       use bitcoin::secp256k1;
-       use prelude::*;
-       use sync::Arc;
-
-       fn create_network_graph() -> NetworkGraph {
-               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
-               NetworkGraph::new(genesis_hash)
-       }
-
-       fn create_gossip_sync(network_graph: &NetworkGraph) -> (
-               Secp256k1<All>, P2PGossipSync<&NetworkGraph, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>
-       ) {
-               let secp_ctx = Secp256k1::new();
-               let logger = Arc::new(test_utils::TestLogger::new());
-               let gossip_sync = P2PGossipSync::new(network_graph, None, Arc::clone(&logger));
-               (secp_ctx, gossip_sync)
-       }
-
-       #[test]
-       fn request_full_sync_finite_times() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-               let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
-
-               assert!(gossip_sync.should_request_full_sync(&node_id));
-               assert!(gossip_sync.should_request_full_sync(&node_id));
-               assert!(gossip_sync.should_request_full_sync(&node_id));
-               assert!(gossip_sync.should_request_full_sync(&node_id));
-               assert!(gossip_sync.should_request_full_sync(&node_id));
-               assert!(!gossip_sync.should_request_full_sync(&node_id));
-       }
-
-       fn get_signed_node_announcement<F: Fn(&mut UnsignedNodeAnnouncement)>(f: F, node_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> NodeAnnouncement {
-               let node_id = PublicKey::from_secret_key(&secp_ctx, node_key);
-               let mut unsigned_announcement = UnsignedNodeAnnouncement {
-                       features: NodeFeatures::known(),
-                       timestamp: 100,
-                       node_id: node_id,
-                       rgb: [0; 3],
-                       alias: [0; 32],
-                       addresses: Vec::new(),
-                       excess_address_data: Vec::new(),
-                       excess_data: Vec::new(),
-               };
-               f(&mut unsigned_announcement);
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               NodeAnnouncement {
-                       signature: secp_ctx.sign_ecdsa(&msghash, node_key),
-                       contents: unsigned_announcement
-               }
-       }
-
-       fn get_signed_channel_announcement<F: Fn(&mut UnsignedChannelAnnouncement)>(f: F, node_1_key: &SecretKey, node_2_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> ChannelAnnouncement {
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_key);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_key);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-
-               let mut unsigned_announcement = UnsignedChannelAnnouncement {
-                       features: ChannelFeatures::known(),
-                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
-                       short_channel_id: 0,
-                       node_id_1,
-                       node_id_2,
-                       bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                       bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                       excess_data: Vec::new(),
-               };
-               f(&mut unsigned_announcement);
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_key),
-                       node_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_key),
-                       bitcoin_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_btckey),
-                       contents: unsigned_announcement,
-               }
-       }
-
-       fn get_channel_script(secp_ctx: &Secp256k1<secp256k1::All>) -> Script {
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-               Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
-                             .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_1_btckey).serialize())
-                             .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_2_btckey).serialize())
-                             .push_opcode(opcodes::all::OP_PUSHNUM_2)
-                             .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
-                             .to_v0_p2wsh()
-       }
-
-       fn get_signed_channel_update<F: Fn(&mut UnsignedChannelUpdate)>(f: F, node_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> ChannelUpdate {
-               let mut unsigned_channel_update = UnsignedChannelUpdate {
-                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
-                       short_channel_id: 0,
-                       timestamp: 100,
-                       flags: 0,
-                       cltv_expiry_delta: 144,
-                       htlc_minimum_msat: 1_000_000,
-                       htlc_maximum_msat: OptionalField::Absent,
-                       fee_base_msat: 10_000,
-                       fee_proportional_millionths: 20,
-                       excess_data: Vec::new()
-               };
-               f(&mut unsigned_channel_update);
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               ChannelUpdate {
-                       signature: secp_ctx.sign_ecdsa(&msghash, node_key),
-                       contents: unsigned_channel_update
-               }
-       }
-
-       #[test]
-       fn handling_node_announcements() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let zero_hash = Sha256dHash::hash(&[0; 32]);
-
-               let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_node_announcement(&valid_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!("No existing channels for node_announcement", e.err)
-               };
-
-               {
-                       // Announce a channel to add a corresponding node.
-                       let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-                       match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                               Ok(res) => assert!(res),
-                               _ => panic!()
-                       };
-               }
-
-               match gossip_sync.handle_node_announcement(&valid_announcement) {
-                       Ok(res) => assert!(res),
-                       Err(_) => panic!()
-               };
-
-               let fake_msghash = hash_to_message!(&zero_hash);
-               match gossip_sync.handle_node_announcement(
-                       &NodeAnnouncement {
-                               signature: secp_ctx.sign_ecdsa(&fake_msghash, node_1_privkey),
-                               contents: valid_announcement.contents.clone()
-               }) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Invalid signature on node_announcement message")
-               };
-
-               let announcement_with_data = get_signed_node_announcement(|unsigned_announcement| {
-                       unsigned_announcement.timestamp += 1000;
-                       unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
-               }, node_1_privkey, &secp_ctx);
-               // Return false because contains excess data.
-               match gossip_sync.handle_node_announcement(&announcement_with_data) {
-                       Ok(res) => assert!(!res),
-                       Err(_) => panic!()
-               };
-
-               // Even though previous announcement was not relayed further, we still accepted it,
-               // so we now won't accept announcements before the previous one.
-               let outdated_announcement = get_signed_node_announcement(|unsigned_announcement| {
-                       unsigned_announcement.timestamp += 1000 - 10;
-               }, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_node_announcement(&outdated_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Update older than last processed update")
-               };
-       }
-
-       #[test]
-       fn handling_channel_announcements() {
-               let secp_ctx = Secp256k1::new();
-               let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-
-               let good_script = get_channel_script(&secp_ctx);
-               let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-
-               // Test if the UTXO lookups were not supported
-               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
-               let mut gossip_sync = P2PGossipSync::new(&network_graph, None, Arc::clone(&logger));
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(res) => assert!(res),
-                       _ => panic!()
-               };
-
-               {
-                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
-                               None => panic!(),
-                               Some(_) => ()
-                       };
-               }
-
-               // If we receive announcement for the same channel (with UTXO lookups disabled),
-               // drop new one on the floor, since we can't see any changes.
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Already have knowledge of channel")
-               };
-
-               // Test if an associated transaction were not on-chain (or not confirmed).
-               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
-               *chain_source.utxo_ret.lock().unwrap() = Err(chain::AccessError::UnknownTx);
-               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
-               gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), Arc::clone(&logger));
-
-               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
-                       unsigned_announcement.short_channel_id += 1;
-               }, node_1_privkey, node_2_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Channel announced without corresponding UTXO entry")
-               };
-
-               // Now test if the transaction is found in the UTXO set and the script is correct.
-               *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: 0, script_pubkey: good_script.clone() });
-               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
-                       unsigned_announcement.short_channel_id += 2;
-               }, node_1_privkey, node_2_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(res) => assert!(res),
-                       _ => panic!()
-               };
-
-               {
-                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
-                               None => panic!(),
-                               Some(_) => ()
-                       };
-               }
-
-               // If we receive announcement for the same channel (but TX is not confirmed),
-               // drop new one on the floor, since we can't see any changes.
-               *chain_source.utxo_ret.lock().unwrap() = Err(chain::AccessError::UnknownTx);
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Channel announced without corresponding UTXO entry")
-               };
-
-               // But if it is confirmed, replace the channel
-               *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: 0, script_pubkey: good_script });
-               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
-                       unsigned_announcement.features = ChannelFeatures::empty();
-                       unsigned_announcement.short_channel_id += 2;
-               }, node_1_privkey, node_2_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(res) => assert!(res),
-                       _ => panic!()
-               };
-               {
-                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
-                               Some(channel_entry) => {
-                                       assert_eq!(channel_entry.features, ChannelFeatures::empty());
-                               },
-                               _ => panic!()
-                       };
-               }
-
-               // Don't relay valid channels with excess data
-               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
-                       unsigned_announcement.short_channel_id += 3;
-                       unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
-               }, node_1_privkey, node_2_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(res) => assert!(!res),
-                       _ => panic!()
-               };
-
-               let mut invalid_sig_announcement = valid_announcement.clone();
-               invalid_sig_announcement.contents.excess_data = Vec::new();
-               match gossip_sync.handle_channel_announcement(&invalid_sig_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Invalid signature on channel_announcement message")
-               };
-
-               let channel_to_itself_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_announcement(&channel_to_itself_announcement) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Channel announcement node had a channel with itself")
-               };
-       }
-
-       #[test]
-       fn handling_channel_update() {
-               let secp_ctx = Secp256k1::new();
-               let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
-               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
-               let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
-               let gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), Arc::clone(&logger));
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-
-               let amount_sats = 1000_000;
-               let short_channel_id;
-
-               {
-                       // Announce a channel we will update
-                       let good_script = get_channel_script(&secp_ctx);
-                       *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: amount_sats, script_pubkey: good_script.clone() });
-
-                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
-                       match gossip_sync.handle_channel_announcement(&valid_channel_announcement) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-
-               }
-
-               let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_update(&valid_channel_update) {
-                       Ok(res) => assert!(res),
-                       _ => panic!()
-               };
-
-               {
-                       match network_graph.read_only().channels().get(&short_channel_id) {
-                               None => panic!(),
-                               Some(channel_info) => {
-                                       assert_eq!(channel_info.one_to_two.as_ref().unwrap().cltv_expiry_delta, 144);
-                                       assert!(channel_info.two_to_one.is_none());
-                               }
-                       };
-               }
-
-               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                       unsigned_channel_update.timestamp += 100;
-                       unsigned_channel_update.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
-               }, node_1_privkey, &secp_ctx);
-               // Return false because contains excess data
-               match gossip_sync.handle_channel_update(&valid_channel_update) {
-                       Ok(res) => assert!(!res),
-                       _ => panic!()
-               };
-
-               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                       unsigned_channel_update.timestamp += 110;
-                       unsigned_channel_update.short_channel_id += 1;
-               }, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_update(&valid_channel_update) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Couldn't find channel for update")
-               };
-
-               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                       unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(MAX_VALUE_MSAT + 1);
-                       unsigned_channel_update.timestamp += 110;
-               }, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_update(&valid_channel_update) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "htlc_maximum_msat is larger than maximum possible msats")
-               };
-
-               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                       unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(amount_sats * 1000 + 1);
-                       unsigned_channel_update.timestamp += 110;
-               }, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_update(&valid_channel_update) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "htlc_maximum_msat is larger than channel capacity or capacity is bogus")
-               };
-
-               // Even though previous update was not relayed further, we still accepted it,
-               // so we now won't accept update before the previous one.
-               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                       unsigned_channel_update.timestamp += 100;
-               }, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_update(&valid_channel_update) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Update had same timestamp as last processed update")
-               };
-
-               let mut invalid_sig_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                       unsigned_channel_update.timestamp += 500;
-               }, node_1_privkey, &secp_ctx);
-               let zero_hash = Sha256dHash::hash(&[0; 32]);
-               let fake_msghash = hash_to_message!(&zero_hash);
-               invalid_sig_channel_update.signature = secp_ctx.sign_ecdsa(&fake_msghash, node_1_privkey);
-               match gossip_sync.handle_channel_update(&invalid_sig_channel_update) {
-                       Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Invalid signature on channel_update message")
-               };
-       }
-
-       #[test]
-       fn handling_network_update() {
-               let logger = test_utils::TestLogger::new();
-               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
-               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
-               let network_graph = NetworkGraph::new(genesis_hash);
-               let gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), &logger);
-               let secp_ctx = Secp256k1::new();
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-
-               {
-                       // There is no nodes in the table at the beginning.
-                       assert_eq!(network_graph.read_only().nodes().len(), 0);
-               }
-
-               let short_channel_id;
-               {
-                       // Announce a channel we will update
-                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
-                       let chain_source: Option<&test_utils::TestChainSource> = None;
-                       assert!(network_graph.update_channel_from_announcement(&valid_channel_announcement, &chain_source, &secp_ctx).is_ok());
-                       assert!(network_graph.read_only().channels().get(&short_channel_id).is_some());
-
-                       let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
-                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_none());
-
-                       gossip_sync.handle_event(&Event::PaymentPathFailed {
-                               payment_id: None,
-                               payment_hash: PaymentHash([0; 32]),
-                               rejected_by_dest: false,
-                               all_paths_failed: true,
-                               path: vec![],
-                               network_update: Some(NetworkUpdate::ChannelUpdateMessage {
-                                       msg: valid_channel_update,
-                               }),
-                               short_channel_id: None,
-                               retry: None,
-                               error_code: None,
-                               error_data: None,
-                       });
-
-                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_some());
-               }
-
-               // Non-permanent closing just disables a channel
-               {
-                       match network_graph.read_only().channels().get(&short_channel_id) {
-                               None => panic!(),
-                               Some(channel_info) => {
-                                       assert!(channel_info.one_to_two.as_ref().unwrap().enabled);
-                               }
-                       };
-
-                       gossip_sync.handle_event(&Event::PaymentPathFailed {
-                               payment_id: None,
-                               payment_hash: PaymentHash([0; 32]),
-                               rejected_by_dest: false,
-                               all_paths_failed: true,
-                               path: vec![],
-                               network_update: Some(NetworkUpdate::ChannelFailure {
-                                       short_channel_id,
-                                       is_permanent: false,
-                               }),
-                               short_channel_id: None,
-                               retry: None,
-                               error_code: None,
-                               error_data: None,
-                       });
-
-                       match network_graph.read_only().channels().get(&short_channel_id) {
-                               None => panic!(),
-                               Some(channel_info) => {
-                                       assert!(!channel_info.one_to_two.as_ref().unwrap().enabled);
-                               }
-                       };
-               }
-
-               // Permanent closing deletes a channel
-               gossip_sync.handle_event(&Event::PaymentPathFailed {
-                       payment_id: None,
-                       payment_hash: PaymentHash([0; 32]),
-                       rejected_by_dest: false,
-                       all_paths_failed: true,
-                       path: vec![],
-                       network_update: Some(NetworkUpdate::ChannelFailure {
-                               short_channel_id,
-                               is_permanent: true,
-                       }),
-                       short_channel_id: None,
-                       retry: None,
-                       error_code: None,
-                       error_data: None,
-               });
-
-               assert_eq!(network_graph.read_only().channels().len(), 0);
-               // Nodes are also deleted because there are no associated channels anymore
-               assert_eq!(network_graph.read_only().nodes().len(), 0);
-               // TODO: Test NetworkUpdate::NodeFailure, which is not implemented yet.
-       }
-
-       #[test]
-       fn test_channel_timeouts() {
-               // Test the removal of channels with `remove_stale_channels`.
-               let logger = test_utils::TestLogger::new();
-               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
-               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
-               let network_graph = NetworkGraph::new(genesis_hash);
-               let gossip_sync = P2PGossipSync::new(&network_graph, Some(chain_source.clone()), &logger);
-               let secp_ctx = Secp256k1::new();
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-
-               let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-               let short_channel_id = valid_channel_announcement.contents.short_channel_id;
-               let chain_source: Option<&test_utils::TestChainSource> = None;
-               assert!(network_graph.update_channel_from_announcement(&valid_channel_announcement, &chain_source, &secp_ctx).is_ok());
-               assert!(network_graph.read_only().channels().get(&short_channel_id).is_some());
-
-               let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
-               assert!(gossip_sync.handle_channel_update(&valid_channel_update).is_ok());
-               assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_some());
-
-               network_graph.remove_stale_channels_with_time(100 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
-               assert_eq!(network_graph.read_only().channels().len(), 1);
-               assert_eq!(network_graph.read_only().nodes().len(), 2);
-
-               network_graph.remove_stale_channels_with_time(101 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
-               #[cfg(feature = "std")]
-               {
-                       // In std mode, a further check is performed before fully removing the channel -
-                       // the channel_announcement must have been received at least two weeks ago. We
-                       // fudge that here by indicating the time has jumped two weeks. Note that the
-                       // directional channel information will have been removed already..
-                       assert_eq!(network_graph.read_only().channels().len(), 1);
-                       assert_eq!(network_graph.read_only().nodes().len(), 2);
-                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_none());
-
-                       use std::time::{SystemTime, UNIX_EPOCH};
-                       let announcement_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
-                       network_graph.remove_stale_channels_with_time(announcement_time + 1 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
-               }
-
-               assert_eq!(network_graph.read_only().channels().len(), 0);
-               assert_eq!(network_graph.read_only().nodes().len(), 0);
-       }
-
-       #[test]
-       fn getting_next_channel_announcements() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-
-               // Channels were not announced yet.
-               let channels_with_announcements = gossip_sync.get_next_channel_announcements(0, 1);
-               assert_eq!(channels_with_announcements.len(), 0);
-
-               let short_channel_id;
-               {
-                       // Announce a channel we will update
-                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
-                       match gossip_sync.handle_channel_announcement(&valid_channel_announcement) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-               }
-
-               // Contains initial channel announcement now.
-               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id, 1);
-               assert_eq!(channels_with_announcements.len(), 1);
-               if let Some(channel_announcements) = channels_with_announcements.first() {
-                       let &(_, ref update_1, ref update_2) = channel_announcements;
-                       assert_eq!(update_1, &None);
-                       assert_eq!(update_2, &None);
-               } else {
-                       panic!();
-               }
-
-
-               {
-                       // Valid channel update
-                       let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                               unsigned_channel_update.timestamp = 101;
-                       }, node_1_privkey, &secp_ctx);
-                       match gossip_sync.handle_channel_update(&valid_channel_update) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-               }
-
-               // Now contains an initial announcement and an update.
-               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id, 1);
-               assert_eq!(channels_with_announcements.len(), 1);
-               if let Some(channel_announcements) = channels_with_announcements.first() {
-                       let &(_, ref update_1, ref update_2) = channel_announcements;
-                       assert_ne!(update_1, &None);
-                       assert_eq!(update_2, &None);
-               } else {
-                       panic!();
-               }
-
-               {
-                       // Channel update with excess data.
-                       let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
-                               unsigned_channel_update.timestamp = 102;
-                               unsigned_channel_update.excess_data = [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec();
-                       }, node_1_privkey, &secp_ctx);
-                       match gossip_sync.handle_channel_update(&valid_channel_update) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-               }
-
-               // Test that announcements with excess data won't be returned
-               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id, 1);
-               assert_eq!(channels_with_announcements.len(), 1);
-               if let Some(channel_announcements) = channels_with_announcements.first() {
-                       let &(_, ref update_1, ref update_2) = channel_announcements;
-                       assert_eq!(update_1, &None);
-                       assert_eq!(update_2, &None);
-               } else {
-                       panic!();
-               }
-
-               // Further starting point have no channels after it
-               let channels_with_announcements = gossip_sync.get_next_channel_announcements(short_channel_id + 1000, 1);
-               assert_eq!(channels_with_announcements.len(), 0);
-       }
-
-       #[test]
-       fn getting_next_node_announcements() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-
-               // No nodes yet.
-               let next_announcements = gossip_sync.get_next_node_announcements(None, 10);
-               assert_eq!(next_announcements.len(), 0);
-
-               {
-                       // Announce a channel to add 2 nodes
-                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-                       match gossip_sync.handle_channel_announcement(&valid_channel_announcement) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-               }
-
-
-               // Nodes were never announced
-               let next_announcements = gossip_sync.get_next_node_announcements(None, 3);
-               assert_eq!(next_announcements.len(), 0);
-
-               {
-                       let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
-                       match gossip_sync.handle_node_announcement(&valid_announcement) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-
-                       let valid_announcement = get_signed_node_announcement(|_| {}, node_2_privkey, &secp_ctx);
-                       match gossip_sync.handle_node_announcement(&valid_announcement) {
-                               Ok(_) => (),
-                               Err(_) => panic!()
-                       };
-               }
-
-               let next_announcements = gossip_sync.get_next_node_announcements(None, 3);
-               assert_eq!(next_announcements.len(), 2);
-
-               // Skip the first node.
-               let next_announcements = gossip_sync.get_next_node_announcements(Some(&node_id_1), 2);
-               assert_eq!(next_announcements.len(), 1);
-
-               {
-                       // Later announcement which should not be relayed (excess data) prevent us from sharing a node
-                       let valid_announcement = get_signed_node_announcement(|unsigned_announcement| {
-                               unsigned_announcement.timestamp += 10;
-                               unsigned_announcement.excess_data = [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec();
-                       }, node_2_privkey, &secp_ctx);
-                       match gossip_sync.handle_node_announcement(&valid_announcement) {
-                               Ok(res) => assert!(!res),
-                               Err(_) => panic!()
-                       };
-               }
-
-               let next_announcements = gossip_sync.get_next_node_announcements(Some(&node_id_1), 2);
-               assert_eq!(next_announcements.len(), 0);
-       }
-
-       #[test]
-       fn network_graph_serialization() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-
-               // Announce a channel to add a corresponding node.
-               let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
-               match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                       Ok(res) => assert!(res),
-                       _ => panic!()
-               };
-
-               let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
-               match gossip_sync.handle_node_announcement(&valid_announcement) {
-                       Ok(_) => (),
-                       Err(_) => panic!()
-               };
-
-               let mut w = test_utils::TestVecWriter(Vec::new());
-               assert!(!network_graph.read_only().nodes().is_empty());
-               assert!(!network_graph.read_only().channels().is_empty());
-               network_graph.write(&mut w).unwrap();
-               assert!(<NetworkGraph>::read(&mut io::Cursor::new(&w.0)).unwrap() == network_graph);
-       }
-
-       #[test]
-       fn network_graph_tlv_serialization() {
-               let network_graph = create_network_graph();
-               network_graph.set_last_rapid_gossip_sync_timestamp(42);
-
-               let mut w = test_utils::TestVecWriter(Vec::new());
-               network_graph.write(&mut w).unwrap();
-               let reassembled_network_graph: NetworkGraph = Readable::read(&mut io::Cursor::new(&w.0)).unwrap();
-               assert!(reassembled_network_graph == network_graph);
-               assert_eq!(reassembled_network_graph.get_last_rapid_gossip_sync_timestamp().unwrap(), 42);
-       }
-
-       #[test]
-       #[cfg(feature = "std")]
-       fn calling_sync_routing_table() {
-               use std::time::{SystemTime, UNIX_EPOCH};
-
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-               let node_privkey_1 = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_privkey_1);
-
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
-
-               // It should ignore if gossip_queries feature is not enabled
-               {
-                       let init_msg = Init { features: InitFeatures::known().clear_gossip_queries(), remote_network_address: None };
-                       gossip_sync.peer_connected(&node_id_1, &init_msg);
-                       let events = gossip_sync.get_and_clear_pending_msg_events();
-                       assert_eq!(events.len(), 0);
-               }
-
-               // It should send a gossip_timestamp_filter with the correct information
-               {
-                       let init_msg = Init { features: InitFeatures::known(), remote_network_address: None };
-                       gossip_sync.peer_connected(&node_id_1, &init_msg);
-                       let events = gossip_sync.get_and_clear_pending_msg_events();
-                       assert_eq!(events.len(), 1);
-                       match &events[0] {
-                               MessageSendEvent::SendGossipTimestampFilter{ node_id, msg } => {
-                                       assert_eq!(node_id, &node_id_1);
-                                       assert_eq!(msg.chain_hash, chain_hash);
-                                       let expected_timestamp = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
-                                       assert!((msg.first_timestamp as u64) >= expected_timestamp - 60*60*24*7*2);
-                                       assert!((msg.first_timestamp as u64) < expected_timestamp - 60*60*24*7*2 + 10);
-                                       assert_eq!(msg.timestamp_range, u32::max_value());
-                               },
-                               _ => panic!("Expected MessageSendEvent::SendChannelRangeQuery")
-                       };
-               }
-       }
-
-       #[test]
-       fn handling_query_channel_range() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-
-               let mut scids: Vec<u64> = vec![
-                       scid_from_parts(0xfffffe, 0xffffff, 0xffff).unwrap(), // max
-                       scid_from_parts(0xffffff, 0xffffff, 0xffff).unwrap(), // never
-               ];
-
-               // used for testing multipart reply across blocks
-               for block in 100000..=108001 {
-                       scids.push(scid_from_parts(block, 0, 0).unwrap());
-               }
-
-               // used for testing resumption on same block
-               scids.push(scid_from_parts(108001, 1, 0).unwrap());
-
-               for scid in scids {
-                       let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
-                               unsigned_announcement.short_channel_id = scid;
-                       }, node_1_privkey, node_2_privkey, &secp_ctx);
-                       match gossip_sync.handle_channel_announcement(&valid_announcement) {
-                               Ok(_) => (),
-                               _ => panic!()
-                       };
-               }
-
-               // Error when number_of_blocks=0
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 0,
-                               number_of_blocks: 0,
-                       },
-                       false,
-                       vec![ReplyChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 0,
-                               number_of_blocks: 0,
-                               sync_complete: true,
-                               short_channel_ids: vec![]
-                       }]
-               );
-
-               // Error when wrong chain
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: genesis_block(Network::Bitcoin).header.block_hash(),
-                               first_blocknum: 0,
-                               number_of_blocks: 0xffff_ffff,
-                       },
-                       false,
-                       vec![ReplyChannelRange {
-                               chain_hash: genesis_block(Network::Bitcoin).header.block_hash(),
-                               first_blocknum: 0,
-                               number_of_blocks: 0xffff_ffff,
-                               sync_complete: true,
-                               short_channel_ids: vec![],
-                       }]
-               );
-
-               // Error when first_blocknum > 0xffffff
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 0x01000000,
-                               number_of_blocks: 0xffff_ffff,
-                       },
-                       false,
-                       vec![ReplyChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 0x01000000,
-                               number_of_blocks: 0xffff_ffff,
-                               sync_complete: true,
-                               short_channel_ids: vec![]
-                       }]
-               );
-
-               // Empty reply when max valid SCID block num
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 0xffffff,
-                               number_of_blocks: 1,
-                       },
-                       true,
-                       vec![
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 0xffffff,
-                                       number_of_blocks: 1,
-                                       sync_complete: true,
-                                       short_channel_ids: vec![]
-                               },
-                       ]
-               );
-
-               // No results in valid query range
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 1000,
-                               number_of_blocks: 1000,
-                       },
-                       true,
-                       vec![
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 1000,
-                                       number_of_blocks: 1000,
-                                       sync_complete: true,
-                                       short_channel_ids: vec![],
-                               }
-                       ]
-               );
-
-               // Overflow first_blocknum + number_of_blocks
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 0xfe0000,
-                               number_of_blocks: 0xffffffff,
-                       },
-                       true,
-                       vec![
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 0xfe0000,
-                                       number_of_blocks: 0xffffffff - 0xfe0000,
-                                       sync_complete: true,
-                                       short_channel_ids: vec![
-                                               0xfffffe_ffffff_ffff, // max
-                                       ]
-                               }
-                       ]
-               );
-
-               // Single block exactly full
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 100000,
-                               number_of_blocks: 8000,
-                       },
-                       true,
-                       vec![
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 100000,
-                                       number_of_blocks: 8000,
-                                       sync_complete: true,
-                                       short_channel_ids: (100000..=107999)
-                                               .map(|block| scid_from_parts(block, 0, 0).unwrap())
-                                               .collect(),
-                               },
-                       ]
-               );
-
-               // Multiple split on new block
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 100000,
-                               number_of_blocks: 8001,
-                       },
-                       true,
-                       vec![
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 100000,
-                                       number_of_blocks: 7999,
-                                       sync_complete: false,
-                                       short_channel_ids: (100000..=107999)
-                                               .map(|block| scid_from_parts(block, 0, 0).unwrap())
-                                               .collect(),
-                               },
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 107999,
-                                       number_of_blocks: 2,
-                                       sync_complete: true,
-                                       short_channel_ids: vec![
-                                               scid_from_parts(108000, 0, 0).unwrap(),
-                                       ],
-                               }
-                       ]
-               );
-
-               // Multiple split on same block
-               do_handling_query_channel_range(
-                       &gossip_sync,
-                       &node_id_2,
-                       QueryChannelRange {
-                               chain_hash: chain_hash.clone(),
-                               first_blocknum: 100002,
-                               number_of_blocks: 8000,
-                       },
-                       true,
-                       vec![
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 100002,
-                                       number_of_blocks: 7999,
-                                       sync_complete: false,
-                                       short_channel_ids: (100002..=108001)
-                                               .map(|block| scid_from_parts(block, 0, 0).unwrap())
-                                               .collect(),
-                               },
-                               ReplyChannelRange {
-                                       chain_hash: chain_hash.clone(),
-                                       first_blocknum: 108001,
-                                       number_of_blocks: 1,
-                                       sync_complete: true,
-                                       short_channel_ids: vec![
-                                               scid_from_parts(108001, 1, 0).unwrap(),
-                                       ],
-                               }
-                       ]
-               );
-       }
-
-       fn do_handling_query_channel_range(
-               gossip_sync: &P2PGossipSync<&NetworkGraph, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
-               test_node_id: &PublicKey,
-               msg: QueryChannelRange,
-               expected_ok: bool,
-               expected_replies: Vec<ReplyChannelRange>
-       ) {
-               let mut max_firstblocknum = msg.first_blocknum.saturating_sub(1);
-               let mut c_lightning_0_9_prev_end_blocknum = max_firstblocknum;
-               let query_end_blocknum = msg.end_blocknum();
-               let result = gossip_sync.handle_query_channel_range(test_node_id, msg);
-
-               if expected_ok {
-                       assert!(result.is_ok());
-               } else {
-                       assert!(result.is_err());
-               }
-
-               let events = gossip_sync.get_and_clear_pending_msg_events();
-               assert_eq!(events.len(), expected_replies.len());
-
-               for i in 0..events.len() {
-                       let expected_reply = &expected_replies[i];
-                       match &events[i] {
-                               MessageSendEvent::SendReplyChannelRange { node_id, msg } => {
-                                       assert_eq!(node_id, test_node_id);
-                                       assert_eq!(msg.chain_hash, expected_reply.chain_hash);
-                                       assert_eq!(msg.first_blocknum, expected_reply.first_blocknum);
-                                       assert_eq!(msg.number_of_blocks, expected_reply.number_of_blocks);
-                                       assert_eq!(msg.sync_complete, expected_reply.sync_complete);
-                                       assert_eq!(msg.short_channel_ids, expected_reply.short_channel_ids);
-
-                                       // Enforce exactly the sequencing requirements present on c-lightning v0.9.3
-                                       assert!(msg.first_blocknum == c_lightning_0_9_prev_end_blocknum || msg.first_blocknum == c_lightning_0_9_prev_end_blocknum.saturating_add(1));
-                                       assert!(msg.first_blocknum >= max_firstblocknum);
-                                       max_firstblocknum = msg.first_blocknum;
-                                       c_lightning_0_9_prev_end_blocknum = msg.first_blocknum.saturating_add(msg.number_of_blocks);
-
-                                       // Check that the last block count is >= the query's end_blocknum
-                                       if i == events.len() - 1 {
-                                               assert!(msg.first_blocknum.saturating_add(msg.number_of_blocks) >= query_end_blocknum);
-                                       }
-                               },
-                               _ => panic!("expected MessageSendEvent::SendReplyChannelRange"),
-                       }
-               }
-       }
-
-       #[test]
-       fn handling_query_short_channel_ids() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, gossip_sync) = create_gossip_sync(&network_graph);
-               let node_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
-
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
-
-               let result = gossip_sync.handle_query_short_channel_ids(&node_id, QueryShortChannelIds {
-                       chain_hash,
-                       short_channel_ids: vec![0x0003e8_000000_0000],
-               });
-               assert!(result.is_err());
-       }
-}
-
-#[cfg(all(test, feature = "_bench_unstable"))]
-mod benches {
-       use super::*;
-
-       use test::Bencher;
-       use std::io::Read;
-
-       #[bench]
-       fn read_network_graph(bench: &mut Bencher) {
-               let mut d = ::routing::router::test_utils::get_route_file().unwrap();
-               let mut v = Vec::new();
-               d.read_to_end(&mut v).unwrap();
-               bench.iter(|| {
-                       let _ = NetworkGraph::read(&mut std::io::Cursor::new(&v)).unwrap();
-               });
-       }
-
-       #[bench]
-       fn write_network_graph(bench: &mut Bencher) {
-               let mut d = ::routing::router::test_utils::get_route_file().unwrap();
-               let net_graph = NetworkGraph::read(&mut d).unwrap();
-               bench.iter(|| {
-                       let _ = net_graph.encode();
-               });
-       }
-}
index 9bf48501c2dd018a9247cf21be10c4c4b5bdd11d..301ae76ddbb315e4aa02cec072e394f0bf87924f 100644 (file)
@@ -17,8 +17,8 @@ use bitcoin::secp256k1::PublicKey;
 use ln::channelmanager::ChannelDetails;
 use ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
 use ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
+use routing::gossip::{DirectedChannelInfoWithUpdate, EffectiveCapacity, NetworkGraph, ReadOnlyNetworkGraph, NodeId, RoutingFees};
 use routing::scoring::{ChannelUsage, Score};
-use routing::network_graph::{DirectedChannelInfoWithUpdate, EffectiveCapacity, NetworkGraph, ReadOnlyNetworkGraph, NodeId, RoutingFees};
 use util::ser::{Writeable, Readable, Writer};
 use util::logger::{Level, Logger};
 use util::chacha20::ChaCha20;
@@ -1858,7 +1858,7 @@ fn build_route_from_hops_internal<L: Deref>(
 
 #[cfg(test)]
 mod tests {
-       use routing::network_graph::{NetworkGraph, P2PGossipSync, NodeId};
+       use routing::gossip::{NetworkGraph, P2PGossipSync, NodeId};
        use routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
                PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
                DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
index 339979b1b020f708e3f1dc55597275f36254250d..54400624dce63a30ec0e506bfc1c87800a6bac4a 100644 (file)
@@ -17,7 +17,7 @@
 //! ```
 //! # extern crate bitcoin;
 //! #
-//! # use lightning::routing::network_graph::NetworkGraph;
+//! # use lightning::routing::gossip::NetworkGraph;
 //! # use lightning::routing::router::{RouteParameters, find_route};
 //! # use lightning::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
 //! # use lightning::chain::keysinterface::{KeysManager, KeysInterface};
@@ -55,7 +55,7 @@
 //! [`find_route`]: crate::routing::router::find_route
 
 use ln::msgs::DecodeError;
-use routing::network_graph::{EffectiveCapacity, NetworkGraph, NodeId};
+use routing::gossip::{EffectiveCapacity, NetworkGraph, NodeId};
 use routing::router::RouteHop;
 use util::ser::{Readable, ReadableArgs, Writeable, Writer};
 use util::logger::Logger;
@@ -1120,9 +1120,9 @@ mod tests {
 
        use ln::features::{ChannelFeatures, NodeFeatures};
        use ln::msgs::{ChannelAnnouncement, ChannelUpdate, OptionalField, UnsignedChannelAnnouncement, UnsignedChannelUpdate};
-       use routing::scoring::{ChannelUsage, Score};
-       use routing::network_graph::{EffectiveCapacity, NetworkGraph, NodeId};
+       use routing::gossip::{EffectiveCapacity, NetworkGraph, NodeId};
        use routing::router::RouteHop;
+       use routing::scoring::{ChannelUsage, Score};
        use util::ser::{ReadableArgs, Writeable};
        use util::test_utils::TestLogger;
 
index b00cf74e062f0d72cbbea7487e8d69591a378be0..db5b064f1f01f7932fa181bc865d8d264998922e 100644 (file)
@@ -21,7 +21,7 @@ use ln::features::ChannelTypeFeatures;
 use ln::msgs;
 use ln::msgs::DecodeError;
 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
-use routing::network_graph::NetworkUpdate;
+use routing::gossip::NetworkUpdate;
 use util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, VecReadWrapper, VecWriteWrapper};
 use routing::router::{RouteHop, RouteParameters};
 
@@ -339,8 +339,8 @@ pub enum Event {
                /// Should be applied to the [`NetworkGraph`] so that routing decisions can take into
                /// account the update. [`P2PGossipSync`] is capable of doing this.
                ///
-               /// [`NetworkGraph`]: crate::routing::network_graph::NetworkGraph
-               /// [`P2PGossipSync`]: crate::routing::network_graph::P2PGossipSync
+               /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
+               /// [`P2PGossipSync`]: crate::routing::gossip::P2PGossipSync
                network_update: Option<NetworkUpdate>,
                /// For both single-path and multi-path payments, this is set if all paths of the payment have
                /// failed. This will be set to false if (1) this is an MPP payment and (2) other parts of the
index 5c124c21afdb25984d9d43362726f858fb292c8b..117eff491b343d4ae6cdfd0d0af7cd7a1df5ae91 100644 (file)
@@ -13,7 +13,7 @@ use bitcoin::hashes::hex::ToHex;
 use io::{self};
 use routing::scoring::WriteableScore;
 
-use crate::{chain::{keysinterface::{Sign, KeysInterface}, self, transaction::{OutPoint}, chaininterface::{BroadcasterInterface, FeeEstimator}, chainmonitor::{Persist, MonitorUpdateId}, channelmonitor::{ChannelMonitor, ChannelMonitorUpdate}}, ln::channelmanager::ChannelManager, routing::network_graph::NetworkGraph};
+use crate::{chain::{keysinterface::{Sign, KeysInterface}, self, transaction::{OutPoint}, chaininterface::{BroadcasterInterface, FeeEstimator}, chainmonitor::{Persist, MonitorUpdateId}, channelmonitor::{ChannelMonitor, ChannelMonitorUpdate}}, ln::channelmanager::ChannelManager, routing::gossip::NetworkGraph};
 use super::{logger::Logger, ser::Writeable};
 
 /// Trait for a key-value store for persisting some writeable object at some key