[EC-598] feat: add ability to throw errors across messenger

apps/browser/src/content/webauthn/messaging/message.ts

@@ -14,6 +14,7 @@ export enum MessageType {
   CredentialGetResponse,
   AbortRequest,
   AbortResponse,
+  ErrorResponse,
 }
 
 export type CredentialCreationRequest = {
@@ -43,6 +44,11 @@ export type AbortRequest = {
   abortedRequestId: string;
 };
 
+export type ErrorResponse = {
+  type: MessageType.ErrorResponse;
+  error: string;
+};
+
 export type AbortResponse = {
   type: MessageType.AbortResponse;
   abortedRequestId: string;
@@ -54,4 +60,5 @@ export type Message =
   | CredentialGetRequest
   | CredentialGetResponse
   | AbortRequest
-  | AbortResponse;
+  | AbortResponse
+  | ErrorResponse;

apps/browser/src/content/webauthn/messaging/messenger.spec.ts

@@ -44,6 +44,17 @@ describe("Messenger", () => {
     expect(returned).toMatchObject(response);
   });
 
+  it("should throw error from B when sending request from A that fails", async () => {
+    const request = createRequest();
+    const error = new Error("Test error");
+    const requestPromise = messengerA.request(request);
+    const received = handlerB.recieve();
+
+    received[0].reject(error);
+
+    await expect(requestPromise).rejects.toThrow();
+  });
+
   it("should deliver abort signal to B when requesting abort", () => {
     const abortController = new AbortController();
     messengerA.request(createRequest(), abortController);
@@ -53,15 +64,6 @@ describe("Messenger", () => {
 
     expect(received[0].abortController.signal.aborted).toBe(true);
   });
-
-  it.skip("should abort request and throw error when abort is requested from A", () => {
-    const abortController = new AbortController();
-    const requestPromise = messengerA.request(createRequest(), abortController);
-
-    abortController.abort();
-
-    expect(requestPromise).toThrow();
-  });
 });
 
 type TestMessage = Message & { testId: string };
@@ -105,6 +107,7 @@ class TestMessageHandler {
   private recievedMessages: {
     message: TestMessage;
     respond: (response: TestMessage) => void;
+    reject: (error: Error) => void;
     abortController?: AbortController;
   }[] = [];
 
@@ -115,6 +118,7 @@ class TestMessageHandler {
           message,
           abortController,
           respond: (response) => resolve(response),
+          reject: (error) => reject(error),
         });
       });
   }

apps/browser/src/content/webauthn/messaging/messenger.ts

@@ -49,15 +49,26 @@ export class Messenger {
 
           const abortController = new AbortController();
           this.abortControllers.set(message.metadata.requestId, abortController);
-          const handlerResponse = await this.handler(message, abortController);
-          this.abortControllers.delete(message.metadata.requestId);
 
-          if (handlerResponse === undefined) {
-            return;
+          try {
+            const handlerResponse = await this.handler(message, abortController);
+
+            if (handlerResponse === undefined) {
+              return;
+            }
+
+            const metadata: Metadata = { requestId: message.metadata.requestId };
+            this.channel.postMessage({ ...handlerResponse, metadata });
+          } catch (error) {
+            const metadata: Metadata = { requestId: message.metadata.requestId };
+            this.channel.postMessage({
+              type: MessageType.ErrorResponse,
+              metadata,
+              error: JSON.stringify(error, Object.getOwnPropertyNames(error)),
+            });
+          } finally {
+            this.abortControllers.delete(message.metadata.requestId);
           }
-
-          const metadata: Metadata = { requestId: message.metadata.requestId };
-          this.channel.postMessage({ ...handlerResponse, metadata });
         })
       )
       .subscribe();
@@ -71,7 +82,7 @@ export class Messenger {
     });
   }
 
-  request(request: Message, abortController?: AbortController): Promise<Message> {
+  async request(request: Message, abortController?: AbortController): Promise<Message> {
     const requestId = Date.now().toString();
     const metadata: Metadata = { requestId };
 
@@ -93,8 +104,15 @@ export class Messenger {
 
     this.channel.postMessage({ ...request, metadata });
 
-    return promise.finally(() =>
-      abortController?.signal.removeEventListener("abort", abortListener)
-    );
+    const response = await promise;
+    abortController?.signal.removeEventListener("abort", abortListener);
+
+    if (response.type === MessageType.ErrorResponse) {
+      const error = new Error();
+      Object.assign(error, JSON.parse(response.error));
+      throw error;
+    }
+
+    return response;
   }
 }