feat: emit an event in EventBus upon dial error

waku/v2/peermanager/peer_connector.go

@@ -272,6 +272,11 @@ func (c *PeerConnectionStrategy) dialPeers() {
 	}
 }
 
+type DialError struct {
+	Err    error
+	PeerID peer.ID
+}
+
 func (c *PeerConnectionStrategy) dialPeer(pi peer.AddrInfo, sem chan struct{}) {
 	defer c.WaitGroup().Done()
 	ctx, cancel := context.WithTimeout(c.Context(), c.dialTimeout)
@@ -281,6 +286,15 @@ func (c *PeerConnectionStrategy) dialPeer(pi peer.AddrInfo, sem chan struct{}) {
 		c.addConnectionBackoff(pi.ID)
 		c.host.Peerstore().(wps.WakuPeerstore).AddConnFailure(pi.ID)
 		c.logger.Warn("connecting to peer", logging.HostID("peerID", pi.ID), zap.Error(err))
+		em, emitterErr := c.host.EventBus().Emitter(new(DialError))
+		if emitterErr != nil {
+			c.logger.Error("error creating DialError emitter", zap.Error(emitterErr))
+		}
+		emitterErr = em.Emit(DialError{Err: err, PeerID: pi.ID})
+		if emitterErr != nil {
+			c.logger.Error("error emitting DialError in event bus", zap.Error(emitterErr))
+		}
+		defer em.Close()
 	}
 	c.host.Peerstore().(wps.WakuPeerstore).ResetConnFailures(pi.ID)
 	<-sem