fix(@aws-amplify/datastore): Retry mutation if GraphQL timeout due to bad network condition.

packages/api-graphql/src/GraphQLAPI.ts

@@ -304,7 +304,7 @@ export class GraphQLAPIClass {
 			}
 			response = {
 				data: {},
-				errors: [new GraphQLError(err.message)],
+				errors: [new GraphQLError(err.message, null, null, null, null, err)],
 			};
 		}
 

packages/datastore/__tests__/mutation.test.ts

@@ -0,0 +1,237 @@
+import { MutationProcessor } from '../src/sync/processors/mutation';
+import { Model as ModelType, testSchema, internalTestSchema } from './helpers';
+import {
+	PersistentModelConstructor,
+	InternalSchema,
+	OpType,
+} from '../src/types';
+import { createMutationInstanceFromModelOperation } from '../src/sync/utils';
+import { MutationEvent } from '../src/sync/';
+
+let syncClasses: any;
+let modelInstanceCreator: any;
+
+describe('MutationProcessor', () => {
+	// Test for this PR: https://github.com/aws-amplify/amplify-js/pull/6542
+	describe('100% Packet Loss Axios Error', () => {
+		let mutationProcessor: MutationProcessor;
+
+		beforeAll(async () => {
+			mutationProcessor = await instantiateMutationProcessor();
+		});
+
+		it('Should result in Network Error and get handled without breaking the Mutation Processor', async () => {
+			const mutationProcessorSpy = jest.spyOn(mutationProcessor, 'resume');
+
+			await mutationProcessor.resume();
+
+			expect(mockJitteredExponentialRetry.mock.results).toHaveLength(1);
+
+			await expect(
+				mockJitteredExponentialRetry.mock.results[0].value
+			).rejects.toEqual(new Error('Network Error'));
+
+			expect(mutationProcessorSpy).toHaveBeenCalled();
+
+			// MutationProcessor.resume exited successfully, i.e., did not throw
+			await expect(mutationProcessorSpy.mock.results[0].value).resolves.toEqual(
+				undefined
+			);
+		});
+	});
+	afterAll(() => {
+		jest.restoreAllMocks();
+	});
+});
+
+// Mocking restClient.post to throw the error we expect
+// when experiencing poor network conditions
+jest.mock('@aws-amplify/api-rest', () => {
+	return {
+		...jest.requireActual('@aws-amplify/api-rest'),
+		RestClient() {
+			return {
+				post: jest.fn().mockImplementation(() => {
+					return Promise.reject(axiosError);
+				}),
+				getCancellableToken: () => {},
+				updateRequestToBeCancellable: () => {},
+				isCancel: () => false,
+			};
+		},
+	};
+});
+
+// Configuring the API category so that API.graphql can be used
+// by the MutationProcessor
+jest.mock('@aws-amplify/api', () => {
+	const awsconfig = {
+		aws_project_region: 'us-west-2',
+		aws_appsync_graphqlEndpoint:
+			'https://xxxxxxxxxxxxxxxxxxxxxx.appsync-api.us-west-2.amazonaws.com/graphql',
+		aws_appsync_region: 'us-west-2',
+		aws_appsync_authenticationType: 'API_KEY',
+		aws_appsync_apiKey: 'da2-xxxxxxxxxxxxxxxxxxxxxx',
+	};
+
+	const { GraphQLAPIClass } = jest.requireActual('@aws-amplify/api-graphql');
+	const graphqlInstance = new GraphQLAPIClass(null);
+	graphqlInstance.configure(awsconfig);
+
+	return {
+		graphql: graphqlInstance.graphql.bind(graphqlInstance),
+	};
+});
+
+// mocking jitteredExponentialRetry to prevent it from retrying
+// endlessly in the mutation processor and so that we can expect the thrown result in our test
+// should throw a Network Error
+let mockJitteredExponentialRetry;
+jest.mock('@aws-amplify/core', () => {
+	mockJitteredExponentialRetry = jest
+		.fn()
+		.mockImplementation(async (fn, args) => {
+			await fn(...args);
+		});
+	return {
+		...jest.requireActual('@aws-amplify/core'),
+		jitteredExponentialRetry: mockJitteredExponentialRetry,
+	};
+});
+
+// Mocking just enough dependencies for us to be able to
+// instantiate a working MutationProcessor
+// includes functional mocked outbox containing a single MutationEvent
+async function instantiateMutationProcessor() {
+	const schema: InternalSchema = internalTestSchema();
+
+	jest.doMock('../src/sync/', () => ({
+		SyncEngine: {
+			getNamespace: () => schema.namespaces['sync'],
+		},
+	}));
+
+	const { initSchema, DataStore } = require('../src/datastore/datastore');
+	const classes = initSchema(testSchema());
+	let Model: PersistentModelConstructor<ModelType>;
+
+	({ Model } = classes as {
+		Model: PersistentModelConstructor<ModelType>;
+	});
+
+	const userClasses = {};
+	userClasses['Model'] = Model;
+
+	await DataStore.start();
+	({ syncClasses } = require('../src/datastore/datastore'));
+	({ modelInstanceCreator } = (DataStore as any).storage.storage);
+
+	const newModel = new Model({
+		field1: 'Some value',
+		dateCreated: new Date().toISOString(),
+	});
+
+	const newMutationEvent = createMutationEvent(newModel, OpType.INSERT);
+	// mocking mutation queue with a single event
+	const mutationQueue = [newMutationEvent];
+
+	const outbox = {
+		peek: () => {
+			return mutationQueue[0];
+		},
+		dequeue: () => {
+			mutationQueue.pop();
+		},
+	};
+
+	const storage = {
+		runExclusive: fn => fn(),
+	};
+
+	const mutationProcessor = new MutationProcessor(
+		schema,
+		storage as any,
+		userClasses,
+		outbox as any,
+		modelInstanceCreator,
+		{} as any
+	);
+
+	(mutationProcessor as any).observer = true;
+
+	return mutationProcessor;
+}
+
+// Creates MutationEvent instance that can be added to the outbox
+async function createMutationEvent(model, opType): Promise<MutationEvent> {
+	const MutationEventConstructor = syncClasses[
+		'MutationEvent'
+	] as PersistentModelConstructor<MutationEvent>;
+
+	const modelConstructor = (Object.getPrototypeOf(model) as Object)
+		.constructor as PersistentModelConstructor<any>;
+
+	return createMutationInstanceFromModelOperation(
+		undefined,
+		undefined,
+		opType,
+		modelConstructor,
+		model,
+		{},
+		MutationEventConstructor,
+		modelInstanceCreator
+	);
+}
+
+// expected error when experiencing 100% packet loss
+const axiosError = {
+	message: 'timeout of 0ms exceeded',
+	name: 'Error',
+	stack:
+		'Error: timeout of 0ms exceeded\n    at createError (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:265622:17)\n    at EventTarget.handleTimeout (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:265537:16)\n    at EventTarget.dispatchEvent (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:32460:27)\n    at EventTarget.setReadyState (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:31623:20)\n    at EventTarget.__didCompleteResponse (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:31443:16)\n    at http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:31553:47\n    at RCTDeviceEventEmitter.emit (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:7202:37)\n    at MessageQueue.__callFunction (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:2813:31)\n    at http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:2545:17\n    at MessageQueue.__guard (http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false:2767:13)',
+	config: {
+		url:
+			'https://xxxxxxxxxxxxxxxxxxxxxx.appsync-api.us-west-2.amazonaws.com/graphql',
+		method: 'post',
+		data:
+			'{"query":"mutation operation($input: UpdatePostInput!, $condition: ModelPostConditionInput) {  updatePost(input: $input, condition: $condition) {    id    title    rating    status    _version    _lastChangedAt    _deleted    blog {      id      _deleted    }  }}","variables":{"input":{"id":"86e8f2c1-b002-4ff2-92a2-3dad37933477","status":"INACTIVE","_version":1},"condition":null}}',
+		headers: {
+			Accept: 'application/json, text/plain, */*',
+			'Content-Type': 'application/json; charset=UTF-8',
+			'User-Agent': 'aws-amplify/3.8.21 react-native',
+			'X-Api-Key': 'da2-xxxxxxxxxxxxxxxxxxxxxx',
+			'x-amz-user-agent': 'aws-amplify/3.8.21 react-native',
+		},
+		transformRequest: [null],
+		transformResponse: [null],
+		timeout: 0,
+		responseType: 'json',
+		xsrfCookieName: 'XSRF-TOKEN',
+		xsrfHeaderName: 'X-XSRF-TOKEN',
+		maxContentLength: -1,
+		maxBodyLength: -1,
+		cancelToken: {
+			promise: {
+				_U: 1,
+				_V: 0,
+				_W: null,
+				_X: {
+					onRejected: null,
+					promise: {
+						_U: 0,
+						_V: 0,
+						_W: null,
+						_X: null,
+					},
+				},
+			},
+		},
+		host: 'xxxxxxxxxxxxxxxxxxxxxx.appsync-api.us-west-2.amazonaws.com',
+		path: '/graphql',
+		signerServiceInfo: {
+			service: 'appsync',
+			region: 'us-west-2',
+		},
+	},
+	code: 'ECONNABORTED',
+};

packages/datastore/src/sync/processors/mutation.ts

@@ -228,7 +228,12 @@ class MutationProcessor {
 					} catch (err) {
 						if (err.errors && err.errors.length > 0) {
 							const [error] = err.errors;
-							if (error.message === 'Network Error') {
+							const { originalError: { code = null } = {} } = error;
+
+							if (
+								error.message === 'Network Error' ||
+								code === 'ECONNABORTED' // refers to axios timeout error caused by device's bad network condition
+							) {
 								if (!this.processing) {
 									throw new NonRetryableError('Offline');
 								}