Merge pull request #116 from libp2p/feat/no-dial-option

Add context option to disable dialing when opening a new stream

go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/libp2p/go-libp2p-crypto v0.0.1
 	github.com/libp2p/go-libp2p-loggables v0.0.1
 	github.com/libp2p/go-libp2p-metrics v0.0.1
-	github.com/libp2p/go-libp2p-net v0.0.1
+	github.com/libp2p/go-libp2p-net v0.0.2
 	github.com/libp2p/go-libp2p-peer v0.0.1
 	github.com/libp2p/go-libp2p-peerstore v0.0.1
 	github.com/libp2p/go-libp2p-protocol v0.0.1

go.sum

@@ -80,6 +80,8 @@ github.com/libp2p/go-libp2p-metrics v0.0.1 h1:yumdPC/P2VzINdmcKZd0pciSUCpou+s0lw
 github.com/libp2p/go-libp2p-metrics v0.0.1/go.mod h1:jQJ95SXXA/K1VZi13h52WZMa9ja78zjyy5rspMsC/08=
 github.com/libp2p/go-libp2p-net v0.0.1 h1:xJ4Vh4yKF/XKb8fd1Ev0ebAGzVjMxXzrxG2kjtU+F5Q=
 github.com/libp2p/go-libp2p-net v0.0.1/go.mod h1:Yt3zgmlsHOgUWSXmt5V/Jpz9upuJBE8EgNU9DrCcR8c=
+github.com/libp2p/go-libp2p-net v0.0.2 h1:qP06u4TYXfl7uW/hzqPhlVVTSA2nw1B/bHBJaUnbh6M=
+github.com/libp2p/go-libp2p-net v0.0.2/go.mod h1:Yt3zgmlsHOgUWSXmt5V/Jpz9upuJBE8EgNU9DrCcR8c=
 github.com/libp2p/go-libp2p-peer v0.0.1 h1:0qwAOljzYewINrU+Kndoc+1jAL7vzY/oY2Go4DCGfyY=
 github.com/libp2p/go-libp2p-peer v0.0.1/go.mod h1:nXQvOBbwVqoP+T5Y5nCjeH4sP9IX/J0AMzcDUVruVoo=
 github.com/libp2p/go-libp2p-peerstore v0.0.1 h1:twKovq8YK5trLrd3nB7PD2Zu9JcyAIdm7Bz9yBWjhq8=

swarm.go

@@ -295,6 +295,10 @@ func (s *Swarm) NewStream(ctx context.Context, p peer.ID) (inet.Stream, error) {
 	for {
 		c := s.bestConnToPeer(p)
 		if c == nil {
+			if nodial, _ := inet.GetNoDial(ctx); nodial {
+				return nil, inet.ErrNoConn
+			}
+
 			if dials >= DialAttempts {
 				return nil, errors.New("max dial attempts exceeded")
 			}

swarm_test.go

@@ -335,3 +335,13 @@ func TestFilterBounds(t *testing.T) {
 		t.Log("got connect")
 	}
 }
+
+func TestNoDial(t *testing.T) {
+	ctx := context.Background()
+	swarms := makeSwarms(ctx, t, 2)
+
+	_, err := swarms[0].NewStream(inet.WithNoDial(ctx, "swarm test"), swarms[1].LocalPeer())
+	if err != inet.ErrNoConn {
+		t.Fatal("should have failed with ErrNoConn")
+	}
+}