#![deny(unused_mut)]
#![deny(unused_variables)]
#![deny(unused_imports)]
-//! This crate exposes functionality to rapidly sync gossip data, aimed primarily at mobile
+//! This crate exposes client functionality to rapidly sync gossip data, aimed primarily at mobile
//! devices.
//!
-//! The server sends a compressed response containing differential gossip data. The gossip data is
-//! formatted compactly, omitting signatures and opportunistically incremental where previous
-//! channel updates are known (a mechanism that is enabled when the timestamp of the last known
-//! channel update is communicated). A reference server implementation can be found
-//! [here](https://github.com/lightningdevkit/rapid-gossip-sync-server).
+//! The rapid gossip sync server will provide a compressed response containing differential gossip
+//! data. The gossip data is formatted compactly, omitting signatures and opportunistically
+//! incremental where previous channel updates are known. This mechanism is enabled when the
+//! timestamp of the last known channel update is communicated. A reference server implementation
+//! can be found [on Github](https://github.com/lightningdevkit/rapid-gossip-sync-server).
//!
-//! An example server request could look as simple as the following. Note that the first ever rapid
-//! sync should use `0` for `last_sync_timestamp`:
+//! The primary benefit of this syncing mechanism is that it allows a low-powered client to offload
+//! the validation of gossip signatures to a semi-trusted server. This enables the client to
+//! privately calculate routes for payments, and to do so much faster than requiring a full
+//! peer-to-peer gossip sync to complete.
+//!
+//! The server calculates its response on the basis of a client-provided `latest_seen` timestamp,
+//! i.e., the server will return all rapid gossip sync data it has seen after the given timestamp.
+//!
+//! # Getting Started
+//! Firstly, the data needs to be retrieved from the server. For example, you could use the server
+//! at <https://rapidsync.lightningdevkit.org> with the following request format:
//!
//! ```shell
//! curl -o rapid_sync.lngossip https://rapidsync.lightningdevkit.org/snapshot/<last_sync_timestamp>
//! ```
+//! Note that the first ever rapid sync should use `0` for `last_sync_timestamp`.
//!
-//! Then, call the network processing function. In this example, we process the update by reading
-//! its contents from disk, which we do by calling the `sync_network_graph_with_file_path` method:
+//! After the gossip data snapshot has been downloaded, one of the client's graph processing
+//! functions needs to be called. In this example, we process the update by reading its contents
+//! from disk, which we do by calling [sync_network_graph_with_file_path]:
//!
//! ```
//! use bitcoin::blockdata::constants::genesis_block;
//! let rapid_sync = RapidGossipSync::new(&network_graph);
//! let new_last_sync_timestamp_result = rapid_sync.sync_network_graph_with_file_path("./rapid_sync.lngossip");
//! ```
-//!
-//! The primary benefit this syncing mechanism provides is that given a trusted server, a
-//! low-powered client can offload the validation of gossip signatures. This enables a client to
-//! privately calculate routes for payments, and do so much faster and earlier than requiring a full
-//! peer-to-peer gossip sync to complete.
-//!
-//! The reason the rapid sync server requires trust is that it could provide bogus data, though at
-//! worst, all that would result in is a fake network topology, which wouldn't enable the server to
-//! steal or siphon off funds. It could, however, reduce the client's privacy by forcing all
-//! payments to be routed via channels the server controls.
-//!
-//! The way a server is meant to calculate this rapid gossip sync data is by using a `latest_seen`
-//! timestamp provided by the client. It's not included in either channel announcement or update,
-//! (not least due to announcements not including any timestamps at all, but only a block height)
-//! but rather, it's a timestamp of when the server saw a particular message.
+//! [sync_network_graph_with_file_path]: RapidGossipSync::sync_network_graph_with_file_path
// Allow and import test features for benching
#![cfg_attr(all(test, feature = "_bench_unstable"), feature(test))]
#[cfg(all(test, feature = "_bench_unstable"))]
extern crate test;
+#[cfg(feature = "std")]
use std::fs::File;
-use std::ops::Deref;
-use std::sync::atomic::{AtomicBool, Ordering};
+use core::ops::Deref;
+use core::sync::atomic::{AtomicBool, Ordering};
+use lightning::io;
use lightning::routing::gossip::NetworkGraph;
use lightning::util::logger::Logger;
-use crate::error::GraphSyncError;
+pub use crate::error::GraphSyncError;
/// Error types that these functions can return
-pub mod error;
+mod error;
/// Core functionality of this crate
-pub mod processing;
+mod processing;
-/// Rapid Gossip Sync struct
+/// The main Rapid Gossip Sync object.
+///
/// See [crate-level documentation] for usage.
///
/// [crate-level documentation]: crate
}
impl<NG: Deref<Target=NetworkGraph<L>>, L: Deref> RapidGossipSync<NG, L> where L::Target: Logger {
- /// Instantiate a new [`RapidGossipSync`] instance
+ /// Instantiate a new [`RapidGossipSync`] instance.
pub fn new(network_graph: NG) -> Self {
Self {
network_graph,
}
}
- /// Sync gossip data from a file
+ /// Sync gossip data from a file.
/// Returns the last sync timestamp to be used the next time rapid sync data is queried.
///
/// `network_graph`: The network graph to apply the updates to
///
/// `sync_path`: Path to the file where the gossip update data is located
///
+ #[cfg(feature = "std")]
pub fn sync_network_graph_with_file_path(
&self,
sync_path: &str,
self.update_network_graph_from_byte_stream(&mut file)
}
+ /// Update network graph from binary data.
+ /// Returns the last sync timestamp to be used the next time rapid sync data is queried.
+ ///
+ /// `network_graph`: network graph to be updated
+ ///
+ /// `update_data`: `&[u8]` binary stream that comprises the update data
+ pub fn update_network_graph(&self, update_data: &[u8]) -> Result<u32, GraphSyncError> {
+ let mut read_cursor = io::Cursor::new(update_data);
+ self.update_network_graph_from_byte_stream(&mut read_cursor)
+ }
+
/// Gets a reference to the underlying [`NetworkGraph`] which was provided in
/// [`RapidGossipSync::new`].
///
&self.network_graph
}
- /// Returns whether a rapid gossip sync has completed at least once
+ /// Returns whether a rapid gossip sync has completed at least once.
pub fn is_initial_sync_complete(&self) -> bool {
self.is_initial_sync_complete.load(Ordering::Acquire)
}
projects / rust-lightning / blobdiff