Merge pull request #208 from libp2p/fix/routed/peer-addrs

RoutedHost: NewStream ensures we have the means to connect to the peer

p2p/host/routed/routed.go

@@ -59,18 +59,12 @@ func (rh *RoutedHost) Connect(ctx context.Context, pi pstore.PeerInfo) error {
 	// Check if we have some addresses in our recent memory.
 	addrs := rh.Peerstore().Addrs(pi.ID)
 	if len(addrs) < 1 {
-
 		// no addrs? find some with the routing system.
-		pi2, err := rh.route.FindPeer(ctx, pi.ID)
+		var err error
+		addrs, err = rh.findPeerAddrs(ctx, pi.ID)
 		if err != nil {
-			return err // couldnt find any :(
-		}
-		if pi2.ID != pi.ID {
-			err = fmt.Errorf("routing failure: provided addrs for different peer")
-			logRoutingErrDifferentPeers(ctx, pi.ID, pi2.ID, err)
 			return err
 		}
-		addrs = pi2.Addrs
 	}
 
 	// if we're here, we got some addrs. let's use our wrapped host to connect.
@@ -78,6 +72,21 @@ func (rh *RoutedHost) Connect(ctx context.Context, pi pstore.PeerInfo) error {
 	return rh.host.Connect(ctx, pi)
 }
 
+func (rh *RoutedHost) findPeerAddrs(ctx context.Context, id peer.ID) ([]ma.Multiaddr, error) {
+	pi, err := rh.route.FindPeer(ctx, id)
+	if err != nil {
+		return nil, err // couldnt find any :(
+	}
+
+	if pi.ID != id {
+		err = fmt.Errorf("routing failure: provided addrs for different peer")
+		logRoutingErrDifferentPeers(ctx, id, pi.ID, err)
+		return nil, err
+	}
+
+	return pi.Addrs, nil
+}
+
 func logRoutingErrDifferentPeers(ctx context.Context, wanted, got peer.ID, err error) {
 	lm := make(lgbl.DeferredMap)
 	lm["error"] = err
@@ -119,6 +128,14 @@ func (rh *RoutedHost) RemoveStreamHandler(pid protocol.ID) {
 }
 
 func (rh *RoutedHost) NewStream(ctx context.Context, p peer.ID, pids ...protocol.ID) (inet.Stream, error) {
+	// Ensure we have a connection, with peer addresses resolved by the routing system (#207)
+	// It is not sufficient to let the underlying host connect, it will most likely not have
+	// any addresses for the peer without any prior connections.
+	err := rh.Connect(ctx, pstore.PeerInfo{ID: p})
+	if err != nil {
+		return nil, err
+	}
+
 	return rh.host.NewStream(ctx, p, pids...)
 }
 func (rh *RoutedHost) Close() error {