Identify: emit useful events after identification (#2759)

* Identify should emit useful events after identification

* Compare strings rather than objects

* Include other fields in emitted event

* Sort addrs when comparing in test

core/event/identify.go

@@ -1,11 +1,40 @@
 package event
 
-import "github.com/libp2p/go-libp2p/core/peer"
+import (
+	"github.com/libp2p/go-libp2p/core/network"
+	"github.com/libp2p/go-libp2p/core/peer"
+	"github.com/libp2p/go-libp2p/core/protocol"
+	"github.com/libp2p/go-libp2p/core/record"
+	"github.com/multiformats/go-multiaddr"
+)
 
 // EvtPeerIdentificationCompleted is emitted when the initial identification round for a peer is completed.
 type EvtPeerIdentificationCompleted struct {
 	// Peer is the ID of the peer whose identification succeeded.
 	Peer peer.ID
+
+	// Conn is the connection we identified.
+	Conn network.Conn
+
+	// ListenAddrs is the list of addresses the peer is listening on.
+	ListenAddrs []multiaddr.Multiaddr
+
+	// Protocols is the list of protocols the peer advertised on this connection.
+	Protocols []protocol.ID
+
+	// SignedPeerRecord is the provided signed peer record of the peer. May be nil.
+	SignedPeerRecord *record.Envelope
+
+	// AgentVersion is like a UserAgent string in browsers, or client version in
+	// bittorrent includes the client name and client.
+	AgentVersion string
+
+	// ProtocolVersion is the protocolVersion field in the identify message
+	ProtocolVersion string
+
+	// ObservedAddr is the our side's connection address as observed by the
+	// peer. This is not verified, the peer could return anything here.
+	ObservedAddr multiaddr.Multiaddr
 }
 
 // EvtPeerIdentificationFailed is emitted when the initial identification round for a peer failed.

p2p/protocol/identify/id.go

@@ -400,8 +400,6 @@ func (ids *idService) IdentifyWait(c network.Conn) <-chan struct{} {
 			ids.emitters.evtPeerIdentificationFailed.Emit(event.EvtPeerIdentificationFailed{Peer: c.RemotePeer(), Reason: err})
 			return
 		}
-
-		ids.emitters.evtPeerIdentificationCompleted.Emit(event.EvtPeerIdentificationCompleted{Peer: c.RemotePeer()})
 	}()
 
 	return e.IdentifyWaitChan
@@ -711,8 +709,16 @@ func (ids *idService) consumeMessage(mes *pb.Identify, c network.Conn, isPush bo
 		})
 	}
 
-	// mes.ObservedAddr
+	obsAddr, err := ma.NewMultiaddrBytes(mes.GetObservedAddr())
-	ids.consumeObservedAddress(mes.GetObservedAddr(), c)
+	if err != nil {
+		log.Debugf("error parsing received observed addr for %s: %s", c, err)
+		obsAddr = nil
+	}
+
+	if obsAddr != nil {
+		// TODO refactor this to use the emitted events instead of having this func call explicitly.
+		ids.observedAddrs.Record(c, obsAddr)
+	}
 
 	// mes.ListenAddrs
 	laddrs := mes.GetListenAddrs()
@@ -763,6 +769,7 @@ func (ids *idService) consumeMessage(mes *pb.Identify, c network.Conn, isPush bo
 		signedAddrs, err := ids.consumeSignedPeerRecord(c.RemotePeer(), signedPeerRecord)
 		if err != nil {
 			log.Debugf("failed to consume signed peer record: %s", err)
+			signedPeerRecord = nil
 		} else {
 			addrs = signedAddrs
 		}
@@ -786,6 +793,18 @@ func (ids *idService) consumeMessage(mes *pb.Identify, c network.Conn, isPush bo
 
 	// get the key from the other side. we may not have it (no-auth transport)
 	ids.consumeReceivedPubKey(c, mes.PublicKey)
+
+	ids.emitters.evtPeerIdentificationCompleted.Emit(event.EvtPeerIdentificationCompleted{
+		Peer:             c.RemotePeer(),
+		Conn:             c,
+		ListenAddrs:      lmaddrs,
+		Protocols:        mesProtocols,
+		SignedPeerRecord: signedPeerRecord,
+		ObservedAddr:     obsAddr,
+		ProtocolVersion:  pv,
+		AgentVersion:     av,
+	})
+
 }
 
 func (ids *idService) consumeSignedPeerRecord(p peer.ID, signedPeerRecord *record.Envelope) ([]ma.Multiaddr, error) {
@@ -919,20 +938,6 @@ func HasConsistentTransport(a ma.Multiaddr, green []ma.Multiaddr) bool {
 	return false
 }
 
-func (ids *idService) consumeObservedAddress(observed []byte, c network.Conn) {
-	if observed == nil {
-		return
-	}
-
-	maddr, err := ma.NewMultiaddrBytes(observed)
-	if err != nil {
-		log.Debugf("error parsing received observed addr for %s: %s", c, err)
-		return
-	}
-
-	ids.observedAddrs.Record(c, maddr)
-}
-
 // addConnWithLock assuems caller holds the connsMu lock
 func (ids *idService) addConnWithLock(c network.Conn) {
 	_, found := ids.conns[c]

p2p/protocol/identify/id_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"slices"
 	"sync"
 	"testing"
 	"time"
@@ -200,12 +201,47 @@ func TestIDService(t *testing.T) {
 
 	// test that we received the "identify completed" event.
 	select {
-	case <-sub.Out():
+	case evtAny := <-sub.Out():
+		assertCorrectEvtPeerIdentificationCompleted(t, evtAny, h2)
 	case <-time.After(3 * time.Second):
 		t.Fatalf("expected EvtPeerIdentificationCompleted event within 10 seconds; none received")
 	}
 }
 
+func assertCorrectEvtPeerIdentificationCompleted(t *testing.T, evtAny interface{}, other host.Host) {
+	t.Helper()
+	evt := evtAny.(event.EvtPeerIdentificationCompleted)
+	require.NotNil(t, evt.Conn)
+	require.Equal(t, other.ID(), evt.Peer)
+
+	require.Equal(t, len(other.Addrs()), len(evt.ListenAddrs))
+	if len(other.Addrs()) == len(evt.ListenAddrs) {
+		otherAddrsStrings := make([]string, len(other.Addrs()))
+		evtAddrStrings := make([]string, len(evt.ListenAddrs))
+		for i, a := range other.Addrs() {
+			otherAddrsStrings[i] = a.String()
+			evtAddrStrings[i] = evt.ListenAddrs[i].String()
+		}
+		slices.Sort(otherAddrsStrings)
+		slices.Sort(evtAddrStrings)
+		require.Equal(t, otherAddrsStrings, evtAddrStrings)
+	}
+
+	otherProtos := other.Mux().Protocols()
+	slices.Sort(otherProtos)
+	evtProtos := evt.Protocols
+	slices.Sort(evtProtos)
+	require.Equal(t, otherProtos, evtProtos)
+	idFromSignedRecord, err := peer.IDFromPublicKey(evt.SignedPeerRecord.PublicKey)
+	require.NoError(t, err)
+	require.Equal(t, other.ID(), idFromSignedRecord)
+	require.Equal(t, peer.PeerRecordEnvelopePayloadType, evt.SignedPeerRecord.PayloadType)
+	var peerRecord peer.PeerRecord
+	evt.SignedPeerRecord.TypedRecord(&peerRecord)
+	require.Equal(t, other.ID(), peerRecord.PeerID)
+	require.Equal(t, other.Addrs(), peerRecord.Addrs)
+}
+
 func TestProtoMatching(t *testing.T) {
 	tcp1, _ := ma.NewMultiaddr("/ip4/1.2.3.4/tcp/1234")
 	tcp2, _ := ma.NewMultiaddr("/ip4/1.2.3.4/tcp/2345")
@@ -665,7 +701,8 @@ func TestLargeIdentifyMessage(t *testing.T) {
 
 	// test that we received the "identify completed" event.
 	select {
-	case <-sub.Out():
+	case evtAny := <-sub.Out():
+		assertCorrectEvtPeerIdentificationCompleted(t, evtAny, h2)
 	case <-time.After(3 * time.Second):
 		t.Fatalf("expected EvtPeerIdentificationCompleted event within 3 seconds; none received")
 	}