fix(core): add cache-control header to cognito identity client

packages/amazon-cognito-identity-js/src/Client.js

@@ -49,15 +49,20 @@ export default class Client {
 	requestWithRetry(operation, params, callback) {
 		const MAX_DELAY_IN_MILLIS = 5 * 1000;
 
-		jitteredExponentialRetry((p) => new Promise((res, rej) => {
-			this.request(operation, p, (error, result) => {
-				if (error) {
-					rej(error);
-				} else {
-					res(result);
-				}
-			});
-		}), [params], MAX_DELAY_IN_MILLIS)
+		jitteredExponentialRetry(
+			p =>
+				new Promise((res, rej) => {
+					this.request(operation, p, (error, result) => {
+						if (error) {
+							rej(error);
+						} else {
+							res(result);
+						}
+					});
+				}),
+			[params],
+			MAX_DELAY_IN_MILLIS
+		)
 			.then(result => callback(null, result))
 			.catch(error => callback(error));
 	}
@@ -112,9 +117,9 @@ export default class Client {
 				// Taken from aws-sdk-js/lib/protocol/json.js
 				// eslint-disable-next-line no-underscore-dangle
 				const code = (data.__type || data.code).split('#').pop();
-				const error = new Error(data.message || data.Message || null)
-				error.name = code
-				error.code = code
+				const error = new Error(data.message || data.Message || null);
+				error.name = code;
+				error.code = code;
 				return callback(error);
 			})
 			.catch(err => {
@@ -126,17 +131,19 @@ export default class Client {
 				) {
 					try {
 						const code = response.headers.get('x-amzn-errortype').split(':')[0];
-						const error = new Error(response.status ? response.status.toString() : null)
-						error.code = code
-						error.name = code
-						error.statusCode = response.status
+						const error = new Error(
+							response.status ? response.status.toString() : null
+						);
+						error.code = code;
+						error.name = code;
+						error.statusCode = response.status;
 						return callback(error);
 					} catch (ex) {
 						return callback(err);
 					}
 					// otherwise check if error is Network error
 				} else if (err instanceof Error && err.message === 'Network error') {
-					err.code = 'NetworkError'
+					err.code = 'NetworkError';
 				}
 				return callback(err);
 			});
@@ -146,7 +153,7 @@ export default class Client {
 const logger = {
 	debug: () => {
 		// Intentionally blank. This package doesn't have logging
-	}
+	},
 };
 
 /**
@@ -159,7 +166,7 @@ class NonRetryableError extends Error {
 	}
 }
 
-const isNonRetryableError = (obj) => {
+const isNonRetryableError = obj => {
 	const key = 'nonRetryable';
 	return obj && obj[key];
 };
@@ -169,9 +176,13 @@ function retry(functionToRetry, args, delayFn, attempt = 1) {
 		throw Error('functionToRetry must be a function');
 	}
 
-	logger.debug(`${functionToRetry.name} attempt #${attempt} with args: ${JSON.stringify(args)}`);
+	logger.debug(
+		`${functionToRetry.name} attempt #${attempt} with args: ${JSON.stringify(
+			args
+		)}`
+	);
 
-	return functionToRetry(...args).catch((err) => {
+	return functionToRetry(...args).catch(err => {
 		logger.debug(`error on ${functionToRetry.name}`, err);
 
 		if (isNonRetryableError(err)) {
@@ -184,12 +195,13 @@ function retry(functionToRetry, args, delayFn, attempt = 1) {
 		logger.debug(`${functionToRetry.name} retrying in ${retryIn} ms`);
 
 		if (retryIn !== false) {
-			return new Promise(res => setTimeout(res, retryIn))
-					.then(() => retry(functionToRetry, args, delayFn, attempt + 1))
+			return new Promise(res => setTimeout(res, retryIn)).then(() =>
+				retry(functionToRetry, args, delayFn, attempt + 1)
+			);
 		} else {
 			throw err;
 		}
-	})
+	});
 }
 
 function jitteredBackoff(maxDelayMs) {
@@ -203,6 +215,10 @@ function jitteredBackoff(maxDelayMs) {
 }
 
 const MAX_DELAY_MS = 5 * 60 * 1000;
-function jitteredExponentialRetry(functionToRetry, args, maxDelayMs = MAX_DELAY_MS) {
-	return retry(functionToRetry, args, jitteredBackoff(maxDelayMs))
-};
+function jitteredExponentialRetry(
+	functionToRetry,
+	args,
+	maxDelayMs = MAX_DELAY_MS
+) {
+	return retry(functionToRetry, args, jitteredBackoff(maxDelayMs));
+}

packages/core/__tests__/Credentials-test.ts

@@ -126,6 +126,9 @@ describe('Credentials test', () => {
 							};
 						}
 					},
+					middlewareStack: {
+						add: (next, _) => {},
+					},
 				};
 			});
 

packages/core/__tests__/Util-test.ts

@@ -6,6 +6,15 @@ import Reachability from '../src/Util/Reachability';
 import { ConsoleLogger as Logger } from '../src/Logger';
 import { urlSafeDecode, urlSafeEncode } from '../src/Util/StringUtils';
 import { DateUtils } from '../src/Util/DateUtils';
+import {
+	createCognitoIdentityClient,
+	middlewareArgs,
+} from '../src/Util/CognitoIdentityClient';
+import { BuildMiddleware, HttpRequest } from '@aws-sdk/types';
+import {
+	GetCredentialsForIdentityCommand,
+	GetIdCommand,
+} from '@aws-sdk/client-cognito-identity';
 
 Logger.LOG_LEVEL = 'DEBUG';
 
@@ -51,6 +60,79 @@ describe('Util', () => {
 		});
 	});
 
+	describe('cognito identity client test', () => {
+		test('client should be instantiated', async () => {
+			const cognitoClient = createCognitoIdentityClient({
+				region: 'us-west-1',
+			});
+			expect(cognitoClient).toBeTruthy();
+			expect.assertions(1);
+		});
+
+		test('middlewareArgs helper should merge headers into request object', async () => {
+			const args = middlewareArgs({
+				request: {
+					headers: {
+						'test-header': '1234',
+					},
+				},
+				input: {},
+			});
+			expect(args.request.headers['test-header']).toEqual('1234');
+			expect(args.request.headers['cache-control']).toEqual('no-store');
+			expect.assertions(2);
+		});
+
+		test('headers should be added by middleware on GetIdCommand', async () => {
+			const requestCacheHeaderValidator: BuildMiddleware<any, any> =
+				next => async args => {
+					// middleware intercept the request and return it early
+					const request = args.request as HttpRequest;
+					const { headers } = request;
+					expect(headers['cache-control']).toEqual('no-store');
+					return { output: {} as any, response: {} as any };
+				};
+
+			const client = createCognitoIdentityClient({ region: 'us-west-1' });
+			client.middlewareStack.addRelativeTo(requestCacheHeaderValidator, {
+				relation: 'after',
+				toMiddleware: 'cacheControlMiddleWare',
+			});
+
+			await client.send(
+				new GetIdCommand({
+					IdentityPoolId: 'us-west-1:12345678-1234-1234-1234-123456789000',
+				})
+			);
+			expect.assertions(1);
+		});
+
+		test('headers should be added by middleware on GetCredentialsForIdentityCommand', async () => {
+			const requestCacheHeaderValidator: BuildMiddleware<any, any> =
+				next => async args => {
+					// middleware intercept the request and return it early
+					const request = args.request as HttpRequest;
+					const { headers } = request;
+					expect(headers['cache-control']).toEqual('no-store');
+					return { output: {} as any, response: {} as any };
+				};
+
+			const client = createCognitoIdentityClient({ region: 'us-west-1' });
+			client.middlewareStack.addRelativeTo(requestCacheHeaderValidator, {
+				relation: 'after',
+				toMiddleware: 'cacheControlMiddleWare',
+			});
+			await client.send(
+				new GetCredentialsForIdentityCommand({
+					IdentityId: '1234',
+					Logins: {},
+				})
+			);
+
+			expect.assertions(1);
+		});
+	});
+
 	test('jitteredExponential retry happy case', async () => {
 		const resolveAt = 3;
 		let attempts = 0;

packages/core/src/Credentials.ts

@@ -4,7 +4,6 @@ import { makeQuerablePromise } from './JS';
 import { FacebookOAuth, GoogleOAuth } from './OAuthHelper';
 import { jitteredExponentialRetry } from './Util';
 import { ICredentials } from './types';
-import { getAmplifyUserAgent } from './Platform';
 import { Amplify } from './Amplify';
 import {
 	fromCognitoIdentity,
@@ -13,13 +12,13 @@ import {
 	FromCognitoIdentityPoolParameters,
 } from '@aws-sdk/credential-provider-cognito-identity';
 import {
-	CognitoIdentityClient,
 	GetIdCommand,
 	GetCredentialsForIdentityCommand,
 } from '@aws-sdk/client-cognito-identity';
 import { CredentialProvider } from '@aws-sdk/types';
 import { parseAWSExports } from './parseAWSExports';
 import { Hub } from './Hub';
+import { createCognitoIdentityClient } from './Util/CognitoIdentityClient';
 
 const logger = new Logger('Credentials');
 
@@ -265,7 +264,8 @@ export class CredentialsClass {
 				parseAWSExports(this._config || {}).Auth
 			);
 		}
-		const { identityPoolId, region, mandatorySignIn, identityPoolRegion } = this._config;
+		const { identityPoolId, region, mandatorySignIn, identityPoolRegion } =
+			this._config;
 
 		if (mandatorySignIn) {
 			return Promise.reject(
@@ -291,9 +291,8 @@ export class CredentialsClass {
 
 		const identityId = (this._identityId = await this._getGuestIdentityId());
 
-		const cognitoClient = new CognitoIdentityClient({
+		const cognitoClient = createCognitoIdentityClient({
 			region: identityPoolRegion || region,
-			customUserAgent: getAmplifyUserAgent(),
 		});
 
 		let credentials = undefined;
@@ -408,9 +407,8 @@ export class CredentialsClass {
 			);
 		}
 
-		const cognitoClient = new CognitoIdentityClient({
+		const cognitoClient = createCognitoIdentityClient({
 			region: identityPoolRegion || region,
-			customUserAgent: getAmplifyUserAgent(),
 		});
 
 		let credentials = undefined;
@@ -435,7 +433,8 @@ export class CredentialsClass {
 	private _setCredentialsFromSession(session): Promise<ICredentials> {
 		logger.debug('set credentials from session');
 		const idToken = session.getIdToken().getJwtToken();
-		const { region, userPoolId, identityPoolId, identityPoolRegion } = this._config;
+		const { region, userPoolId, identityPoolId, identityPoolRegion } =
+			this._config;
 		if (!identityPoolId) {
 			logger.debug('No Cognito Federated Identity pool provided');
 			return Promise.reject('No Cognito Federated Identity pool provided');
@@ -450,9 +449,8 @@ export class CredentialsClass {
 		const logins = {};
 		logins[key] = idToken;
 
-		const cognitoClient = new CognitoIdentityClient({
+		const cognitoClient = createCognitoIdentityClient({
 			region: identityPoolRegion || region,
-			customUserAgent: getAmplifyUserAgent(),
 		});
 
 		/* 

packages/core/src/Util/CognitoIdentityClient.ts

@@ -0,0 +1,48 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+import {
+	CognitoIdentityClient,
+	CognitoIdentityClientConfig,
+} from '@aws-sdk/client-cognito-identity';
+import { Provider } from '@aws-sdk/types';
+import { getAmplifyUserAgent } from '../Platform';
+
+/**
+ * Returns a CognitoIdentityClient with middleware
+ * @param {CognitoIdentityClientConfig} config
+ * @return {CognitoIdentityClient}
+ */
+export function createCognitoIdentityClient(
+	config: CognitoIdentityClientConfig
+): CognitoIdentityClient {
+	const client = new CognitoIdentityClient({
+		region: config.region,
+		customUserAgent: getAmplifyUserAgent(),
+	});
+
+	client.middlewareStack.add(
+		(next, _) => (args: any) => {
+			return next(middlewareArgs(args));
+		},
+		{
+			step: 'build',
+			name: 'cacheControlMiddleWare',
+		}
+	);
+
+	return client;
+}
+
+export function middlewareArgs(args: { request: any; input: any }) {
+	return {
+		...args,
+		request: {
+			...args.request,
+			headers: {
+				...args.request.headers,
+				'cache-control': 'no-store',
+			},
+		},
+	};
+}