fix(realtime): wrap malformed transcription frames

vincentkoc · vincentkoc · commit 278e3eabf29d · 2026-05-14T19:05:46.000+08:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -52,6 +52,7 @@ Docs: https://docs.openclaw.ai
 - CLI/export-trajectory: report malformed encoded request JSON with a stable CLI error instead of leaking raw parser output.
 - Twilio voice-call: report malformed successful API JSON responses with provider-owned errors instead of leaking raw parser failures.
 - Voice-call provider APIs: report malformed successful guarded JSON responses with provider-prefixed errors instead of leaking raw parser failures.
+- Realtime transcription: report malformed provider websocket JSON frames with owned parser errors instead of leaking raw `SyntaxError` objects.
 - Models config/auth: stop inferring provider env-var markers from broad `^[A-Z_][A-Z0-9_]*$` strings, and resolve config-backed provider `apiKey` values only through structured env SecretRefs (`secrets.providers[id]` / `secrets.defaults`), so unrelated env vars cannot accidentally become provider credentials. Thanks @sallyom.
 - Media fetch: skip allocating and buffering the response body for bodyless media responses (HEAD probes and 204-style empty bodies), avoiding wasted heap on streams that carry no payload. Thanks @shakkernerd.
 - CLI/onboarding: forward provider-specific auth flags (e.g. `--openai-api-key`) through the onboarding wizard so they reach provider auth methods via `ctx.opts`, letting `--openai-api-key "$OPENAI_API_KEY"` skip the redundant "use existing env var?" prompt in non-interactive harnesses. (#81669) Thanks @sjf.
diff --git a/src/realtime-transcription/websocket-session.test.ts b/src/realtime-transcription/websocket-session.test.ts
@@ -15,6 +15,7 @@ afterEach(async () => {
 async function createRealtimeServer(params?: {
   closeOnConnection?: boolean;
   initialEvent?: unknown;
+  initialText?: string;
   onUpgrade?: (headers: Record<string, string | string[] | undefined>) => void;
   onBinary?: (payload: Buffer) => void;
   onText?: (payload: unknown) => void;
@@ -35,6 +36,9 @@ async function createRealtimeServer(params?: {
       if (params?.initialEvent) {
         ws.send(JSON.stringify(params.initialEvent));
       }
+      if (params?.initialText) {
+        ws.send(params.initialText);
+      }
       ws.on("message", (data, isBinary) => {
         const buffer = Buffer.isBuffer(data)
           ? data
@@ -257,6 +261,32 @@ describe("createRealtimeTranscriptionWebSocketSession", () => {
     expect(setupError.message).toBe("nope");
   });
 
+  it("reports malformed websocket JSON with an owned parser error", async () => {
+    const server = await createRealtimeServer({ initialText: "{not json" });
+    const onError = vi.fn();
+    const session = createRealtimeTranscriptionWebSocketSession({
+      providerId: "test",
+      callbacks: { onError },
+      url: server.url,
+      readyOnOpen: true,
+      onMessage: () => {
+        throw new Error("malformed payload should not reach provider handler");
+      },
+      sendAudio: (audio, transport) => {
+        transport.sendBinary(audio);
+      },
+    });
+
+    await session.connect();
+    await vi.waitFor(() => {
+      expect(onError).toHaveBeenCalledTimes(1);
+    });
+    const parseError = requireFirstMockArg(onError, "malformed websocket json error");
+    expect(parseError).toBeInstanceOf(Error);
+    expect(parseError.message).toBe("Realtime transcription websocket received malformed JSON.");
+    session.close();
+  });
+
   it("reports pre-ready closes separately from connection timeouts", async () => {
     const server = await createRealtimeServer({ closeOnConnection: true });
     const onError = vi.fn();
diff --git a/src/realtime-transcription/websocket-session.ts b/src/realtime-transcription/websocket-session.ts
@@ -58,7 +58,11 @@ function rawWsDataToBuffer(data: RawData): Buffer {
 }
 
 function defaultParseMessage(payload: Buffer): unknown {
-  return JSON.parse(payload.toString());
+  try {
+    return JSON.parse(payload.toString()) as unknown;
+  } catch {
+    throw new Error("Realtime transcription websocket received malformed JSON.");
+  }
 }
 
 class WebSocketRealtimeTranscriptionSession<Event> implements RealtimeTranscriptionSession {

Original file line number	Diff line number	Diff line change
`@@ -58,7 +58,11 @@ function rawWsDataToBuffer(data: RawData): Buffer {`
`58`	`58`	`}`
`59`	`59`
`60`	`60`	`function defaultParseMessage(payload: Buffer): unknown {`
`61`		`- return JSON.parse(payload.toString());`
	`61`	`+ try {`
	`62`	`+ return JSON.parse(payload.toString()) as unknown;`
	`63`	`+ } catch {`
	`64`	`+ throw new Error("Realtime transcription websocket received malformed JSON.");`
	`65`	`+ }`
`62`	`66`	`}`
`63`	`67`
`64`	`68`	`class WebSocketRealtimeTranscriptionSession<Event> implements RealtimeTranscriptionSession {`