fix(ping): honor ping interval in case of errors

This PR adds a delay to ping connection handler after exceeding the failure rate to prevent opening a outbound stream right after an error.

Resolves #4410.

Pull-Request: #4423.

Cargo.toml

@@ -84,7 +84,7 @@ libp2p-mplex = { version = "0.40.0", path = "muxers/mplex" }
 libp2p-muxer-test-harness = { path = "muxers/test-harness" }
 libp2p-noise = { version = "0.43.1", path = "transports/noise" }
 libp2p-perf = { version = "0.2.0", path = "protocols/perf" }
-libp2p-ping = { version = "0.43.0", path = "protocols/ping" }
+libp2p-ping = { version = "0.43.1", path = "protocols/ping" }
 libp2p-plaintext = { version = "0.40.0", path = "transports/plaintext" }
 libp2p-pnet = { version = "0.23.0", path = "transports/pnet" }
 libp2p-quic = { version = "0.9.2", path = "transports/quic" }

protocols/ping/CHANGELOG.md

@@ -1,3 +1,11 @@
+## 0.43.1 - unreleased
+
+- Honor ping interval in case of errors.
+  Previously, we would immediately open another ping stream if the current one failed.
+  See [PR 4423].
+
+[PR 4423]: https://github.com/libp2p/rust-libp2p/pull/4423
+
 ## 0.43.0 
 
 - Raise MSRV to 1.65.

protocols/ping/Cargo.toml

@@ -3,7 +3,7 @@ name = "libp2p-ping"
 edition = "2021"
 rust-version = { workspace = true }
 description = "Ping protocol for libp2p"
-version = "0.43.0"
+version = "0.43.1"
 authors = ["Parity Technologies <[email protected]>"]
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"

protocols/ping/src/handler.rs

@@ -303,6 +303,7 @@ impl ConnectionHandler for Handler {
                         return Poll::Ready(ConnectionHandlerEvent::NotifyBehaviour(Ok(rtt)));
                     }
                     Poll::Ready(Err(e)) => {
+                        self.interval.reset(self.config.interval);
                         self.pending_errors.push_front(e);
                     }
                 },
@@ -321,13 +322,16 @@ impl ConnectionHandler for Handler {
                     self.outbound = Some(OutboundState::OpenStream);
                     break;
                 }
-                None => {
-                    self.outbound = Some(OutboundState::OpenStream);
-                    let protocol = SubstreamProtocol::new(ReadyUpgrade::new(PROTOCOL_NAME), ());
-                    return Poll::Ready(ConnectionHandlerEvent::OutboundSubstreamRequest {
-                        protocol,
-                    });
-                }
+                None => match self.interval.poll_unpin(cx) {
+                    Poll::Pending => break,
+                    Poll::Ready(()) => {
+                        self.outbound = Some(OutboundState::OpenStream);
+                        let protocol = SubstreamProtocol::new(ReadyUpgrade::new(PROTOCOL_NAME), ());
+                        return Poll::Ready(ConnectionHandlerEvent::OutboundSubstreamRequest {
+                            protocol,
+                        });
+                    }
+                },
             }
         }
 

protocols/ping/src/protocol.rs

@@ -35,8 +35,7 @@ pub const PROTOCOL_NAME: StreamProtocol = StreamProtocol::new("/ipfs/ping/1.0.0"
 ///
 /// At most a single inbound and outbound substream is kept open at
 /// any time. In case of a ping timeout or another error on a substream, the
-/// substream is dropped. If a configurable number of consecutive
-/// outbound pings fail, the connection is closed.
+/// substream is dropped.
 ///
 /// Successful pings report the round-trip time.
 ///