do not mark the routing table as updated after a FindPeer query. bootstrap logic now uses GetClosestPeers instead of FindPeer. FindPeer can return addresses even if not Connected as long as it was either recently connected (CanConnect) or was discovered during the lookup.

dht_bootstrap.go

@@ -8,7 +8,6 @@ import (
 	multierror "github.com/hashicorp/go-multierror"
 	process "github.com/jbenet/goprocess"
 	processctx "github.com/jbenet/goprocess/context"
-	"github.com/libp2p/go-libp2p-core/routing"
 	kbucket "github.com/libp2p/go-libp2p-kbucket"
 	"github.com/multiformats/go-multiaddr"
 	_ "github.com/multiformats/go-multiaddr-dns"
@@ -58,8 +57,8 @@ func (dht *IpfsDHT) startSelfLookup() error {
 
 			// Do a self walk
 			queryCtx, cancel := context.WithTimeout(ctx, dht.rtRefreshQueryTimeout)
-			_, err := dht.FindPeer(queryCtx, dht.self)
-			if err == routing.ErrNotFound || err == kbucket.ErrLookupFailure {
+			_, err := dht.GetClosestPeers(queryCtx, string(dht.self))
+			if err == kbucket.ErrLookupFailure {
 				err = nil
 			} else if err != nil {
 				err = fmt.Errorf("failed to query self during routing table refresh: %s", err)
@@ -207,10 +206,7 @@ func (dht *IpfsDHT) refreshCpls(ctx context.Context) error {
 
 		// walk to the generated peer
 		walkFnc := func(c context.Context) error {
-			_, err := dht.FindPeer(c, randPeer)
-			if err == routing.ErrNotFound {
-				return nil
-			}
+			_, err := dht.GetClosestPeers(c, string(randPeer))
 			return err
 		}
 

routing.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"github.com/libp2p/go-libp2p-core/network"
+	"github.com/libp2p/go-libp2p-kad-dht/qpeerset"
 	"sync"
 	"time"
 
@@ -688,22 +689,21 @@ func (dht *IpfsDHT) FindPeer(ctx context.Context, id peer.ID) (_ peer.AddrInfo,
 		return peer.AddrInfo{}, err
 	}
 
-	// refresh the cpl for this key if we discovered the peer because of the query
-	if ctx.Err() == nil {
-		discoveredPeerDuringQuery := false
-		for _, p := range lookupRes.peers {
-			if p == id {
-				discoveredPeerDuringQuery = true
-				break
-			}
-		}
-		if discoveredPeerDuringQuery || lookupRes.completed {
-			dht.routingTable.ResetCplRefreshedAtForID(kb.ConvertPeerID(id), time.Now())
+	dialedPeerDuringQuery := false
+	for i, p := range lookupRes.peers {
+		if p == id {
+			// Note: we consider PeerUnreachable to be a valid state because the peer may not support the DHT protocol
+			// and therefore the peer would fail the query. The fact that a peer that is returned can be a non-DHT
+			// server peer and is not identified as such is a bug.
+			dialedPeerDuringQuery = lookupRes.state[i] != qpeerset.PeerHeard
+			break
 		}
 	}
 
-	// TODO: Consider unlucky disconnect timing and potentially utilizing network.CanConnect or something similar
-	if dht.host.Network().Connectedness(id) == network.Connected {
+	// Return peer information if we tried to dial the peer during the query or we are (or recently were) connected
+	// to the peer.
+	connectedness := dht.host.Network().Connectedness(id)
+	if dialedPeerDuringQuery || connectedness == network.Connected || connectedness == network.CanConnect {
 		return dht.peerstore.PeerInfo(id), nil
 	}