Flush after handshake

kylecarbs · kylecarbs · commit aa1e664e4ac6 · 2022-01-27T19:46:57.000Z
diff --git a/peer/conn.go b/peer/conn.go
@@ -283,22 +283,6 @@ func (c *Conn) negotiate() {
 		return
 	}
 
-	// The ICE transport resets when the remote description is updated.
-	// Adding ICE candidates before this point causes a failed connection,
-	// because the candidate would be lost.
-	c.pendingCandidatesMutex.Lock()
-	defer c.pendingCandidatesMutex.Unlock()
-	for _, pendingCandidate := range c.pendingRemoteCandidates {
-		c.opts.Logger.Debug(context.Background(), "flushing remote candidate")
-		err := c.rtc.AddICECandidate(pendingCandidate)
-		if err != nil {
-			_ = c.CloseWithError(xerrors.Errorf("flush pending candidates: %w", err))
-			return
-		}
-	}
-	c.pendingCandidatesFlushed = true
-	c.opts.Logger.Debug(context.Background(), "flushed remote candidates")
-
 	if !c.offerrer {
 		answer, err := c.rtc.CreateAnswer(&webrtc.AnswerOptions{})
 		if err != nil {
@@ -320,6 +304,22 @@ func (c *Conn) negotiate() {
 		case c.localSessionDescriptionChannel <- answer:
 		}
 	}
+
+	// The ICE transport resets when the remote description is updated.
+	// Adding ICE candidates before this point causes a failed connection,
+	// because the candidate would be lost.
+	c.pendingCandidatesMutex.Lock()
+	defer c.pendingCandidatesMutex.Unlock()
+	for _, pendingCandidate := range c.pendingRemoteCandidates {
+		c.opts.Logger.Debug(context.Background(), "flushing remote candidate")
+		err := c.rtc.AddICECandidate(pendingCandidate)
+		if err != nil {
+			_ = c.CloseWithError(xerrors.Errorf("flush pending candidates: %w", err))
+			return
+		}
+	}
+	c.pendingCandidatesFlushed = true
+	c.opts.Logger.Debug(context.Background(), "flushed remote candidates")
 }
 
 // LocalCandidate returns a channel that emits when a local candidate
