fix(extension): coalesce daemon websocket connects (#1554)

Author: jackwener

extension/dist/background.js

@@ -626,6 +626,7 @@ let reconnectAttempts = 0;
 const CONTEXT_ID_KEY = "opencli_context_id_v1";
 let currentContextId = "default";
 let contextIdPromise = null;
+let connectInFlight = null;
 async function getCurrentContextId() {
   if (contextIdPromise) return contextIdPromise;
   contextIdPromise = (async () => {
@@ -698,17 +699,30 @@ console.error = (...args) => {
   _origError(...args);
   forwardLog("error", args);
 };
-async function connect() {
-  if (ws?.readyState === WebSocket.OPEN || ws?.readyState === WebSocket.CONNECTING) return;
+function isDaemonSocketActive(socket = ws) {
+  return socket?.readyState === WebSocket.OPEN || socket?.readyState === WebSocket.CONNECTING;
+}
+function connect() {
+  if (isDaemonSocketActive()) return Promise.resolve();
+  if (connectInFlight) return connectInFlight;
+  connectInFlight = connectAttempt().finally(() => {
+    connectInFlight = null;
+  });
+  return connectInFlight;
+}
+async function connectAttempt() {
+  if (isDaemonSocketActive()) return;
   try {
     const res = await fetch(DAEMON_PING_URL, { signal: AbortSignal.timeout(1e3) });
     if (!res.ok) return;
   } catch {
     return;
   }
+  if (isDaemonSocketActive()) return;
   let thisWs;
   try {
     const contextId = await getCurrentContextId();
+    if (isDaemonSocketActive()) return;
     thisWs = new WebSocket(DAEMON_WS_URL);
     ws = thisWs;
     currentContextId = contextId;

extension/src/background.test.ts

@@ -52,6 +52,16 @@ class MockWebSocket {
   }
 }
 
+function deferred<T>() {
+  let resolve!: (value: T | PromiseLike<T>) => void;
+  let reject!: (reason?: unknown) => void;
+  const promise = new Promise<T>((res, rej) => {
+    resolve = res;
+    reject = rej;
+  });
+  return { promise, resolve, reject };
+}
+
 function createChromeMock() {
   let nextTabId = 10;
   let nextGroupId = 100;
@@ -694,6 +704,31 @@ describe('background tab isolation', () => {
     });
   });
 
+  it('coalesces concurrent daemon connection attempts while the probe is in flight', async () => {
+    const { chrome } = createChromeMock();
+    vi.stubGlobal('chrome', chrome);
+    const ping = deferred<{ ok: boolean }>();
+    const fetchMock = vi.fn(() => ping.promise);
+    vi.stubGlobal('fetch', fetchMock);
+
+    await import('./background');
+    await vi.waitFor(() => {
+      expect(fetchMock).toHaveBeenCalledTimes(1);
+    });
+
+    const onAlarmListener = chrome.alarms.onAlarm.addListener.mock.calls[0][0];
+    await onAlarmListener({ name: 'keepalive' });
+    await onAlarmListener({ name: 'keepalive' });
+
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+    expect(MockWebSocket.instances).toHaveLength(0);
+
+    ping.resolve({ ok: true });
+    await vi.waitFor(() => {
+      expect(MockWebSocket.instances).toHaveLength(1);
+    });
+  });
+
   it('ignores daemon commands delivered to a superseded WebSocket', async () => {
     const { chrome } = createChromeMock();
     vi.stubGlobal('chrome', chrome);

extension/src/background.ts

@@ -18,6 +18,7 @@ let reconnectAttempts = 0;
 const CONTEXT_ID_KEY = 'opencli_context_id_v1';
 let currentContextId = 'default';
 let contextIdPromise: Promise<string> | null = null;
+let connectInFlight: Promise<void> | null = null;
 
 async function getCurrentContextId(): Promise<string> {
   if (contextIdPromise) return contextIdPromise;
@@ -92,26 +93,41 @@ console.error = (...args: unknown[]) => { _origError(...args); forwardLog('error
 
 // ─── WebSocket connection ────────────────────────────────────────────
 
+function isDaemonSocketActive(socket: WebSocket | null | undefined = ws): boolean {
+  return socket?.readyState === WebSocket.OPEN || socket?.readyState === WebSocket.CONNECTING;
+}
+
 /**
  * Probe the daemon via its /ping HTTP endpoint before attempting a WebSocket
  * connection.  fetch() failures are silently catchable; new WebSocket() is not
  * — Chrome logs ERR_CONNECTION_REFUSED to the extension error page before any
  * JS handler can intercept it.  By keeping the probe inside connect() every
  * call site remains unchanged and the guard can never be accidentally skipped.
  */
-async function connect(): Promise<void> {
-  if (ws?.readyState === WebSocket.OPEN || ws?.readyState === WebSocket.CONNECTING) return;
+function connect(): Promise<void> {
+  if (isDaemonSocketActive()) return Promise.resolve();
+  if (connectInFlight) return connectInFlight;
+  connectInFlight = connectAttempt().finally(() => {
+    connectInFlight = null;
+  });
+  return connectInFlight;
+}
+
+async function connectAttempt(): Promise<void> {
+  if (isDaemonSocketActive()) return;
 
   try {
     const res = await fetch(DAEMON_PING_URL, { signal: AbortSignal.timeout(1000) });
     if (!res.ok) return; // unexpected response — not our daemon
   } catch {
     return; // daemon not running — skip WebSocket to avoid console noise
   }
+  if (isDaemonSocketActive()) return;
 
   let thisWs: WebSocket;
   try {
     const contextId = await getCurrentContextId();
+    if (isDaemonSocketActive()) return;
     thisWs = new WebSocket(DAEMON_WS_URL);
     ws = thisWs;
     currentContextId = contextId;