Drop `PeerManager` type bound on `UtxoLookup` entirely

In 67659677d4fdb6bf418d66dfa37c61706425232b we relaxed the bounds
set on `UtxoLookup` to enable those using `RoutingMessageHandler`
other than `P2PGossipSync` to use `UtxoLookup`. Sadly, because this
requires having a concrete `PeerManager` type which does *not* use
`UtxoLookup` in the `RoutingMessageHandler` type, this broke users
who were directly using `P2PGossipSync`.

We could split `UtxoLookup` into two, with different bounds, for
the two use-cases, but instead here we simply switch to storing a
reference to the `PeerManager` via a `dyn Fn` which allows us to
wake the `PeerManager` when we need to.

Fixes #2813

diff --git a/lightning-block-sync/src/gossip.rs b/lightning-block-sync/src/gossip.rs
index 591b0298793ffb3baadb1d0ee0009b1199a95941..9cd4049679c30fd5d7ddd2f86562d6df81758447 100644 (file)
--- a/lightning-block-sync/src/gossip.rs
+++ b/lightning-block-sync/src/gossip.rs
@@ -132,14 +132,12 @@ impl<
 pub struct GossipVerifier<S: FutureSpawner,
        Blocks: Deref + Send + Sync + 'static + Clone,
        L: Deref + Send + Sync + 'static,
-       APM: Deref + Send + Sync + 'static + Clone,
 > where
        Blocks::Target: UtxoSource,
        L::Target: Logger,
-       APM::Target: APeerManager,
 {
        source: Blocks,
-       peer_manager: APM,
+       peer_manager_wake: Arc<dyn Fn() + Send + Sync>,
        gossiper: Arc<P2PGossipSync<Arc<NetworkGraph<L>>, Self, L>>,
        spawn: S,
        block_cache: Arc<Mutex<VecDeque<(u32, Block)>>>,
@@ -150,19 +148,20 @@ const BLOCK_CACHE_SIZE: usize = 5;
 impl<S: FutureSpawner,
        Blocks: Deref + Send + Sync + Clone,
        L: Deref + Send + Sync,
-       APM: Deref + Send + Sync + Clone,
-> GossipVerifier<S, Blocks, L, APM> where
+> GossipVerifier<S, Blocks, L> where
        Blocks::Target: UtxoSource,
        L::Target: Logger,
-       APM::Target: APeerManager,
 {
        /// Constructs a new [`GossipVerifier`].
        ///
        /// This is expected to be given to a [`P2PGossipSync`] (initially constructed with `None` for
        /// the UTXO lookup) via [`P2PGossipSync::add_utxo_lookup`].
-       pub fn new(source: Blocks, spawn: S, gossiper: Arc<P2PGossipSync<Arc<NetworkGraph<L>>, Self, L>>, peer_manager: APM) -> Self {
+       pub fn new<APM: Deref + Send + Sync + Clone + 'static>(
+               source: Blocks, spawn: S, gossiper: Arc<P2PGossipSync<Arc<NetworkGraph<L>>, Self, L>>, peer_manager: APM
+       ) -> Self where APM::Target: APeerManager {
+               let peer_manager_wake = Arc::new(move || peer_manager.as_ref().process_events());
                Self {
-                       source, spawn, gossiper, peer_manager,
+                       source, spawn, gossiper, peer_manager_wake,
                        block_cache: Arc::new(Mutex::new(VecDeque::with_capacity(BLOCK_CACHE_SIZE))),
                }
        }
@@ -252,11 +251,9 @@ impl<S: FutureSpawner,
 impl<S: FutureSpawner,
        Blocks: Deref + Send + Sync + Clone,
        L: Deref + Send + Sync,
-       APM: Deref + Send + Sync + Clone,
-> Deref for GossipVerifier<S, Blocks, L, APM> where
+> Deref for GossipVerifier<S, Blocks, L> where
        Blocks::Target: UtxoSource,
        L::Target: Logger,
-       APM::Target: APeerManager,
 {
        type Target = Self;
        fn deref(&self) -> &Self { self }
@@ -266,11 +263,9 @@ impl<S: FutureSpawner,
 impl<S: FutureSpawner,
        Blocks: Deref + Send + Sync + Clone,
        L: Deref + Send + Sync,
-       APM: Deref + Send + Sync + Clone,
-> UtxoLookup for GossipVerifier<S, Blocks, L, APM> where
+> UtxoLookup for GossipVerifier<S, Blocks, L> where
        Blocks::Target: UtxoSource,
        L::Target: Logger,
-       APM::Target: APeerManager,
 {
        fn get_utxo(&self, _chain_hash: &ChainHash, short_channel_id: u64) -> UtxoResult {
                let res = UtxoFuture::new();
@@ -278,11 +273,11 @@ impl<S: FutureSpawner,
                let source = self.source.clone();
                let gossiper = Arc::clone(&self.gossiper);
                let block_cache = Arc::clone(&self.block_cache);
-               let pm = self.peer_manager.clone();
+               let pmw = Arc::clone(&self.peer_manager_wake);
                self.spawn.spawn(async move {
                        let res = Self::retrieve_utxo(source, block_cache, short_channel_id).await;
                        fut.resolve(gossiper.network_graph(), &*gossiper, res);
-                       pm.as_ref().process_events();
+                       (pmw)();
                });
                UtxoResult::Async(res)
        }