Add client config param IgnoreTURNResolveErrors

Author: amanakin

client.go

@@ -47,6 +47,8 @@ type ClientConfig struct {
 	Conn           net.PacketConn // Listening socket (net.PacketConn)
 	Net            transport.Net
 	LoggerFactory  logging.LoggerFactory
+
+	IgnoreTURNResolveErrors bool // TURN server address is not required for some configurations (e.g. proxy)
 }
 
 // Client is a STUN server client.
@@ -114,10 +116,13 @@ func NewClient(config *ClientConfig) (*Client, error) {
 	if len(config.TURNServerAddr) > 0 {
 		turnServ, err = config.Net.ResolveUDPAddr("udp4", config.TURNServerAddr)
 		if err != nil {
-			return nil, err
+			if !config.IgnoreTURNResolveErrors {
+				return nil, err
+			}
+			log.Debugf("Failed to resolve TURN server %s: %s", config.TURNServerAddr, err)
+		} else {
+			log.Debugf("Resolved TURN server %s to %s", config.TURNServerAddr, turnServ)
 		}
-
-		log.Debugf("Resolved TURN server %s to %s", config.TURNServerAddr, turnServ)
 	}
 
 	client := &Client{

client_test.go

@@ -291,10 +291,13 @@ func TestTCPClientWithoutAddress(t *testing.T) {
 	assert.NoError(t, err)
 
 	client, err := NewClient(&ClientConfig{
-		Conn:     NewSTUNConn(conn),
-		Username: "foo",
-		Password: "pass",
-		RTO:      time.Nanosecond,
+		TURNServerAddr: "unresolvable.turn.server.address:13478",
+		Conn:           NewSTUNConn(conn),
+		Username:       "foo",
+		Password:       "pass",
+		RTO:            time.Nanosecond,
+
+		IgnoreTURNResolveErrors: true,
 	})
 	assert.NoError(t, err)
 	assert.NoError(t, client.Listen())