Ensure transport manager is reset before attempting legacy fallback path (#1893)

Co-authored-by: cnderrauber <zengjiestc@gmail.com>

.changeset/rotten-points-collect.md

@@ -0,0 +1,5 @@
+---
+"livekit-client": patch
+---
+
+Ensure transport manager is reset before attempting legacy fallback path

examples/demo/index.html

@@ -310,7 +310,7 @@
               class="btn btn-outline-secondary btn-sm"
               type="button"
               onclick="appActions.cancelChatReceive()"
-              style="display: none;"
+              style="display: none"
             >
               Cancel current receive
             </button>

src/room/RTCEngine.ts

@@ -220,6 +220,8 @@ export default class RTCEngine extends (EventEmitter as new () => TypedEventEmit
 
   private shouldFailNext: boolean = false;
 
+  private shouldFailOnV1Path: boolean = false;
+
   private regionUrlProvider?: RegionUrlProvider;
 
   private log = log;
@@ -321,9 +323,16 @@ export default class RTCEngine extends (EventEmitter as new () => TypedEventEmit
           offerProto = toProtoSessionDescription(offer.offer, offer.offerId);
         }
       }
+
       if (abortSignal?.aborted) {
         throw ConnectionError.cancelled('Connection aborted');
       }
+
+      if (!useV0Path && this.shouldFailOnV1Path) {
+        this.shouldFailOnV1Path = false;
+        throw ConnectionError.serviceNotFound('Simulated v1 path failure', 'v0-rtc');
+      }
+      log.warn('joining signal with ', url);
       const joinResponse = await this.client.join(
         url,
         token,
@@ -383,6 +392,10 @@ export default class RTCEngine extends (EventEmitter as new () => TypedEventEmit
           }
         } else if (e.reason === ConnectionErrorReason.ServiceNotFound) {
           this.log.warn(`Initial connection failed: ${e.message} – Retrying`);
+          if (this.pcManager) {
+            this.pcManager.onStateChange = undefined;
+            await this.cleanupPeerConnections();
+          }
           return this.join(url, token, opts, abortSignal, true);
         }
       }
@@ -1860,6 +1873,12 @@ export default class RTCEngine extends (EventEmitter as new () => TypedEventEmit
     this.shouldFailNext = true;
   }
 
+  /* @internal */
+  failNextV1Path() {
+    // debugging method to fail the next connection attempt for /rtc/v1 to trigger the fallback version
+    this.shouldFailOnV1Path = true;
+  }
+
   private dataChannelsInfo(): DataChannelInfo[] {
     const infos: DataChannelInfo[] = [];
     const getInfo = (dc: RTCDataChannel | undefined, target: SignalTarget) => {

src/room/Room.ts

@@ -1137,6 +1137,9 @@ class Room extends (EventEmitter as new () => TypedEmitter<RoomEventCallbacks>)
         // @ts-expect-error function is private
         await this.engine.client.handleOnClose('simulate disconnect');
         break;
+      case 'fail-on-v1-path':
+        this.engine.failNextV1Path();
+        break;
       case 'speaker':
         req = new SimulateScenario({
           scenario: {

src/room/types.ts

@@ -92,7 +92,8 @@ export type SimulationScenario =
   | 'disconnect-signal-on-resume'
   | 'disconnect-signal-on-resume-no-messages'
   // instructs the server to send a full reconnect reconnect action to the client
-  | 'leave-full-reconnect';
+  | 'leave-full-reconnect'
+  | 'fail-on-v1-path';
 
 export type LoggerOptions = {
   loggerName?: string;