Add addresses field for closing listeners (#1485)

* Add addresses field for closing listeners

Add an addresses field to the ListenersEvent and the ListenerClosed to
hold the addresses of a listener that has just closed. When we return a
ListenerClosed network event loop over the addresses and call
inject_expired_listen_address on each one.

Fixes: #1482

* Use Vec instead of SmallVec

In order to not expose a third party dependency in our API use a `Vec`
type for the addresses list instead of a `SmallVec`.

* Do not clone for ListenersEvent::Closed

We would like to avoid clones where possible for efficiency reasons.
When returning a `ListenersEvent::Closed` we are already consuming the
listener (by way of a pin projection).  We can therefore use a consuming
iterator instead of cloning.

Use `drain(..).collect()` instead of clone to consume the addresses when
returning a `ListenersEvent::Closed`.

* Expire addresses before listener

The listener and its addresses technically expire at the same time, but
since here we have to pick an order, it makes more sense that the
addresses expire first.

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

core/src/connection/listeners.rs

@@ -148,6 +148,8 @@ where
     Closed {
         /// The ID of the listener that closed.
         listener_id: ListenerId,
+        /// The addresses that the listener was listening on.
+        addresses: Vec<Multiaddr>,
         /// Reason for the closure. Contains `Ok(())` if the stream produced `None`, or `Err`
         /// if the stream produced an error.
         reason: Result<(), TTrans::Error>,
@@ -283,12 +285,14 @@ where
                 Poll::Ready(None) => {
                     return Poll::Ready(ListenersEvent::Closed {
                         listener_id: *listener_project.id,
+                        addresses: listener_project.addresses.drain(..).collect(),
                         reason: Ok(()),
                     })
                 }
                 Poll::Ready(Some(Err(err))) => {
                     return Poll::Ready(ListenersEvent::Closed {
                         listener_id: *listener_project.id,
+                        addresses: listener_project.addresses.drain(..).collect(),
                         reason: Err(err),
                     })
                 }
@@ -351,9 +355,10 @@ where
                 .field("listener_id", listener_id)
                 .field("local_addr", local_addr)
                 .finish(),
-            ListenersEvent::Closed { listener_id, reason } => f
+            ListenersEvent::Closed { listener_id, addresses, reason } => f
                 .debug_struct("ListenersEvent::Closed")
                 .field("listener_id", listener_id)
+                .field("addresses", addresses)
                 .field("reason", reason)
                 .finish(),
             ListenersEvent::Error { listener_id, error } => f

core/src/network.rs

@@ -356,8 +356,8 @@ where
             Poll::Ready(ListenersEvent::AddressExpired { listener_id, listen_addr }) => {
                 return Poll::Ready(NetworkEvent::ExpiredListenerAddress { listener_id, listen_addr })
             }
-            Poll::Ready(ListenersEvent::Closed { listener_id, reason }) => {
-                return Poll::Ready(NetworkEvent::ListenerClosed { listener_id, reason })
+            Poll::Ready(ListenersEvent::Closed { listener_id, addresses, reason }) => {
+                return Poll::Ready(NetworkEvent::ListenerClosed { listener_id, addresses, reason })
             }
             Poll::Ready(ListenersEvent::Error { listener_id, error }) => {
                 return Poll::Ready(NetworkEvent::ListenerError { listener_id, error })

core/src/network/event.rs

@@ -54,6 +54,8 @@ where
     ListenerClosed {
         /// The listener ID that closed.
         listener_id: ListenerId,
+        /// The addresses that the listener was listening on.
+        addresses: Vec<Multiaddr>,
         /// Reason for the closure. Contains `Ok(())` if the stream produced `None`, or `Err`
         /// if the stream produced an error.
         reason: Result<(), TTrans::Error>,
@@ -182,9 +184,10 @@ where
                     .field("listen_addr", listen_addr)
                     .finish()
             }
-            NetworkEvent::ListenerClosed { listener_id, reason } => {
+            NetworkEvent::ListenerClosed { listener_id, addresses, reason } => {
                 f.debug_struct("ListenerClosed")
                     .field("listener_id", listener_id)
+                    .field("addresses", addresses)
                     .field("reason", reason)
                     .finish()
             }
@@ -342,4 +345,3 @@ where
         self.info().to_connected_point()
     }
 }
-

swarm/src/lib.rs

@@ -445,8 +445,11 @@ where TBehaviour: NetworkBehaviour<ProtocolsHandler = THandler>,
                     this.behaviour.inject_expired_listen_addr(&listen_addr);
                     return Poll::Ready(SwarmEvent::ExpiredListenAddr(listen_addr));
                 }
-                Poll::Ready(NetworkEvent::ListenerClosed { listener_id, reason }) => {
+                Poll::Ready(NetworkEvent::ListenerClosed { listener_id, addresses, reason }) => {
                     log::debug!("Listener {:?}; Closed by {:?}.", listener_id, reason);
+                    for addr in addresses.iter() {
+                        this.behaviour.inject_expired_listen_addr(addr);
+                    }
                     this.behaviour.inject_listener_closed(listener_id);
                 }
                 Poll::Ready(NetworkEvent::ListenerError { listener_id, error }) =>