fix: account for EVENT_SUBSCRIBE_ERROR in AppSync (#14491)

* fix: account for EVENT_SUBSCRIBE_ERROR in AppSync

Author: adrianjoshua-strutt

packages/api-graphql/__tests__/AWSAppSyncEventProvider.test.ts

@@ -227,6 +227,45 @@ describe('AppSyncEventProvider', () => {
 					expect(socketCloseSpy).toHaveBeenCalledWith(3001);
 				});
 
+				test('subscription observer error is triggered when a subscribe_error message is received', async () => {
+					expect.assertions(2);
+
+					const observer = provider.subscribe({
+						appSyncGraphqlEndpoint: 'ws://localhost:8080',
+					});
+
+					observer.subscribe({
+						error: e => {
+							expect(e.errors[0].message).toEqual(
+								'Connection failed: AuthorizationError: Not authorized to access channel',
+							);
+						},
+					});
+
+					await fakeWebSocketInterface?.standardConnectionHandshake();
+					await fakeWebSocketInterface?.startAckMessage({
+						connectionTimeoutMs: 100,
+					});
+
+					// Send a subscribe_error message
+					await fakeWebSocketInterface?.sendDataMessage({
+						id: fakeWebSocketInterface?.webSocket.subscriptionId,
+						type: MESSAGE_TYPES.EVENT_SUBSCRIBE_ERROR,
+						errors: [
+							{
+								errorType: 'AuthorizationError',
+								message: 'Not authorized to access channel',
+							},
+						],
+					});
+
+					// Verify error was logged
+					expect(loggerSpy).toHaveBeenCalledWith(
+						'DEBUG',
+						expect.stringContaining('Connection failed:'),
+					);
+				});
+
 				test('subscription observer error is not triggered when a connection is formed and a retriable connection_error data message is received', async () => {
 					expect.assertions(2);
 

packages/api-graphql/src/Providers/AWSWebSocketProvider/index.ts

@@ -684,7 +684,10 @@ export abstract class AWSWebSocketProvider {
 			return;
 		}
 
-		if (type === MESSAGE_TYPES.GQL_ERROR) {
+		if (
+			type === MESSAGE_TYPES.GQL_ERROR ||
+			type === MESSAGE_TYPES.EVENT_SUBSCRIBE_ERROR
+		) {
 			const subscriptionState = SUBSCRIPTION_STATUS.FAILED;
 			if (observer) {
 				this.subscriptionObserverMap.set(id, {
@@ -697,15 +700,23 @@ export abstract class AWSWebSocketProvider {
 					subscriptionState,
 				});
 
-				this.logger.debug(
-					`${CONTROL_MSG.CONNECTION_FAILED}: ${JSON.stringify(payload ?? data)}`,
-				);
+				let errorMessage = JSON.stringify(payload ?? data);
+
+				if (type === MESSAGE_TYPES.EVENT_SUBSCRIBE_ERROR) {
+					const { errors } = JSON.parse(String(message.data));
+					if (Array.isArray(errors) && errors.length > 0) {
+						const error = errors[0];
+						errorMessage = `${error.errorType}: ${error.message}`;
+					}
+				}
+
+				this.logger.debug(`${CONTROL_MSG.CONNECTION_FAILED}: ${errorMessage}`);
 
 				observer.error({
 					errors: [
 						{
 							...new GraphQLError(
-								`${CONTROL_MSG.CONNECTION_FAILED}: ${JSON.stringify(payload ?? data)}`,
+								`${CONTROL_MSG.CONNECTION_FAILED}: ${errorMessage}`,
 							),
 						},
 					],

packages/api-graphql/src/Providers/constants.ts

@@ -93,6 +93,11 @@ export enum MESSAGE_TYPES {
 	 * This is the ack response from AWS AppSync Events to EVENT_STOP message
 	 */
 	EVENT_COMPLETE = 'unsubscribe_success',
+	/**
+	 * Server -> Client message.
+	 * This message type is for sending error messages from AWS AppSync Events to the client
+	 */
+	EVENT_SUBSCRIBE_ERROR = 'subscribe_error',
 }
 
 export enum SUBSCRIPTION_STATUS {