Implement heartbeat controller

packages/app/package.json

@@ -40,6 +40,7 @@
     "@firebase/util": "1.4.2",
     "@firebase/logger": "0.3.2",
     "@firebase/component": "0.5.9",
+    "idb": "3.0.2",
     "tslib": "^2.1.0"
   },
   "license": "Apache-2.0",

packages/app/src/errors.ts

@@ -23,7 +23,11 @@ export const enum AppError {
   DUPLICATE_APP = 'duplicate-app',
   APP_DELETED = 'app-deleted',
   INVALID_APP_ARGUMENT = 'invalid-app-argument',
-  INVALID_LOG_ARGUMENT = 'invalid-log-argument'
+  INVALID_LOG_ARGUMENT = 'invalid-log-argument',
+  STORAGE_OPEN = 'storage-open',
+  STORAGE_GET = 'storage-get',
+  STORAGE_WRITE = 'storage-set',
+  STORAGE_DELETE = 'storage-delete'
 }
 
 const ERRORS: ErrorMap<AppError> = {
@@ -38,7 +42,15 @@ const ERRORS: ErrorMap<AppError> = {
     'firebase.{$appName}() takes either no argument or a ' +
     'Firebase App instance.',
   [AppError.INVALID_LOG_ARGUMENT]:
-    'First argument to `onLog` must be null or a function.'
+    'First argument to `onLog` must be null or a function.',
+  [AppError.STORAGE_OPEN]:
+    'Error thrown when opening storage. Original error: {$originalErrorMessage}.',
+  [AppError.STORAGE_GET]:
+    'Error thrown when reading from storage. Original error: {$originalErrorMessage}.',
+  [AppError.STORAGE_WRITE]:
+    'Error thrown when writing to storage. Original error: {$originalErrorMessage}.',
+  [AppError.STORAGE_DELETE]:
+    'Error thrown when deleting from storage. Original error: {$originalErrorMessage}.'
 };
 
 interface ErrorParams {
@@ -47,6 +59,10 @@ interface ErrorParams {
   [AppError.DUPLICATE_APP]: { appName: string };
   [AppError.APP_DELETED]: { appName: string };
   [AppError.INVALID_APP_ARGUMENT]: { appName: string };
+  [AppError.STORAGE_OPEN]: { originalErrorMessage?: string };
+  [AppError.STORAGE_GET]: { originalErrorMessage?: string };
+  [AppError.STORAGE_WRITE]: { originalErrorMessage?: string };
+  [AppError.STORAGE_DELETE]: { originalErrorMessage?: string };
 }
 
 export const ERROR_FACTORY = new ErrorFactory<AppError, ErrorParams>(

packages/app/src/heartbeatService.test.ts

@@ -0,0 +1,216 @@
+/**
+ * @license
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { expect } from 'chai';
+import '../test/setup';
+import { HeartbeatServiceImpl } from './heartbeatService';
+import {
+  Component,
+  ComponentType,
+  ComponentContainer
+} from '@firebase/component';
+import { PlatformLoggerService } from './types';
+import { FirebaseApp } from './public-types';
+import * as firebaseUtil from '@firebase/util';
+import { SinonStub, stub, useFakeTimers } from 'sinon';
+import * as indexedDb from './indexeddb';
+import { isIndexedDBAvailable } from '@firebase/util';
+
+declare module '@firebase/component' {
+  interface NameServiceMapping {
+    'platform-logger': PlatformLoggerService;
+  }
+}
+
+const USER_AGENT_STRING_1 = 'vs1/1.2.3 vs2/2.3.4';
+const USER_AGENT_STRING_2 = 'different/1.2.3';
+
+describe('HeartbeatServiceImpl', () => {
+  describe('If IndexedDB has no entries', () => {
+    let heartbeatService: HeartbeatServiceImpl;
+    let clock = useFakeTimers();
+    let userAgentString = USER_AGENT_STRING_1;
+    let writeStub: SinonStub;
+    before(() => {
+      const container = new ComponentContainer('heartbeatTestContainer');
+      container.addComponent(
+        new Component(
+          'app',
+          () =>
+            ({
+              options: { appId: 'an-app-id' },
+              name: 'an-app-name'
+            } as FirebaseApp),
+          ComponentType.VERSION
+        )
+      );
+      container.addComponent(
+        new Component(
+          'platform-logger',
+          () => ({ getPlatformInfoString: () => userAgentString }),
+          ComponentType.VERSION
+        )
+      );
+      heartbeatService = new HeartbeatServiceImpl(container);
+    });
+    beforeEach(() => {
+      clock = useFakeTimers();
+      writeStub = stub(heartbeatService._storage, 'overwrite');
+    });
+    /**
+     * NOTE: The clock is being reset between each test because of the global
+     * restore() in test/setup.ts. Don't assume previous clock state.
+     */
+    it(`triggerHeartbeat() stores a heartbeat`, async () => {
+      await heartbeatService.triggerHeartbeat();
+      expect(heartbeatService._heartbeatsCache?.length).to.equal(1);
+      const heartbeat1 = heartbeatService._heartbeatsCache?.[0];
+      expect(heartbeat1?.userAgent).to.equal(USER_AGENT_STRING_1);
+      expect(heartbeat1?.dates[0]).to.equal('1970-01-01');
+      expect(writeStub).to.be.calledWith([heartbeat1]);
+    });
+    it(`triggerHeartbeat() doesn't store another heartbeat on the same day`, async () => {
+      await heartbeatService.triggerHeartbeat();
+      const heartbeat1 = heartbeatService._heartbeatsCache?.[0];
+      expect(heartbeat1?.dates.length).to.equal(1);
+    });
+    it(`triggerHeartbeat() does store another heartbeat on a different day`, async () => {
+      clock.tick(24 * 60 * 60 * 1000);
+      await heartbeatService.triggerHeartbeat();
+      const heartbeat1 = heartbeatService._heartbeatsCache?.[0];
+      expect(heartbeat1?.dates.length).to.equal(2);
+      expect(heartbeat1?.dates[1]).to.equal('1970-01-02');
+    });
+    it(`triggerHeartbeat() stores another entry for a different user agent`, async () => {
+      userAgentString = USER_AGENT_STRING_2;
+      clock.tick(2 * 24 * 60 * 60 * 1000);
+      await heartbeatService.triggerHeartbeat();
+      expect(heartbeatService._heartbeatsCache?.length).to.equal(2);
+      const heartbeat2 = heartbeatService._heartbeatsCache?.[1];
+      expect(heartbeat2?.dates.length).to.equal(1);
+      expect(heartbeat2?.dates[0]).to.equal('1970-01-03');
+    });
+    it('getHeartbeatHeaders() gets stored heartbeats and clears heartbeats', async () => {
+      const deleteStub = stub(heartbeatService._storage, 'deleteAll');
+      const heartbeatHeaders = firebaseUtil.base64Decode(
+        await heartbeatService.getHeartbeatsHeader()
+      );
+      expect(heartbeatHeaders).to.include(USER_AGENT_STRING_1);
+      expect(heartbeatHeaders).to.include(USER_AGENT_STRING_2);
+      expect(heartbeatHeaders).to.include('1970-01-01');
+      expect(heartbeatHeaders).to.include('1970-01-02');
+      expect(heartbeatHeaders).to.include('1970-01-03');
+      expect(heartbeatHeaders).to.include(`"version":2`);
+      expect(heartbeatService._heartbeatsCache).to.equal(null);
+      const emptyHeaders = await heartbeatService.getHeartbeatsHeader();
+      expect(emptyHeaders).to.equal('');
+      expect(deleteStub).to.be.called;
+    });
+  });
+  describe('If IndexedDB has entries', () => {
+    let heartbeatService: HeartbeatServiceImpl;
+    let clock = useFakeTimers();
+    let writeStub: SinonStub;
+    let userAgentString = USER_AGENT_STRING_1;
+    const mockIndexedDBHeartbeats = [
+      {
+        userAgent: 'old-user-agent',
+        dates: ['1969-01-01', '1969-01-02']
+      }
+    ];
+    before(() => {
+      const container = new ComponentContainer('heartbeatTestContainer');
+      container.addComponent(
+        new Component(
+          'app',
+          () =>
+            ({
+              options: { appId: 'an-app-id' },
+              name: 'an-app-name'
+            } as FirebaseApp),
+          ComponentType.VERSION
+        )
+      );
+      container.addComponent(
+        new Component(
+          'platform-logger',
+          () => ({ getPlatformInfoString: () => userAgentString }),
+          ComponentType.VERSION
+        )
+      );
+      stub(indexedDb, 'readHeartbeatsFromIndexedDB').resolves({
+        heartbeats: [...mockIndexedDBHeartbeats]
+      });
+      heartbeatService = new HeartbeatServiceImpl(container);
+    });
+    beforeEach(() => {
+      clock = useFakeTimers();
+      writeStub = stub(heartbeatService._storage, 'overwrite');
+    });
+    /**
+     * NOTE: The clock is being reset between each test because of the global
+     * restore() in test/setup.ts. Don't assume previous clock state.
+     */
+    it(`new heartbeat service reads from indexedDB cache`, async () => {
+      const promiseResult = await heartbeatService._heartbeatsCachePromise;
+      if (isIndexedDBAvailable()) {
+        expect(promiseResult).to.deep.equal(mockIndexedDBHeartbeats);
+        expect(heartbeatService._heartbeatsCache).to.deep.equal(
+          mockIndexedDBHeartbeats
+        );
+      } else {
+        // In Node or other no-indexed-db environments it will fail the
+        // `canUseIndexedDb` check and return an empty array.
+        expect(promiseResult).to.deep.equal([]);
+        expect(heartbeatService._heartbeatsCache).to.deep.equal([]);
+      }
+    });
+    it(`triggerHeartbeat() writes new heartbeats without removing old ones`, async () => {
+      userAgentString = USER_AGENT_STRING_2;
+      clock.tick(3 * 24 * 60 * 60 * 1000);
+      await heartbeatService.triggerHeartbeat();
+      if (isIndexedDBAvailable()) {
+        expect(writeStub).to.be.calledWith([
+          ...mockIndexedDBHeartbeats,
+          { userAgent: USER_AGENT_STRING_2, dates: ['1970-01-04'] }
+        ]);
+      } else {
+        expect(writeStub).to.be.calledWith([
+          { userAgent: USER_AGENT_STRING_2, dates: ['1970-01-04'] }
+        ]);
+      }
+    });
+    it('getHeartbeatHeaders() gets stored heartbeats and clears heartbeats', async () => {
+      const deleteStub = stub(heartbeatService._storage, 'deleteAll');
+      const heartbeatHeaders = firebaseUtil.base64Decode(
+        await heartbeatService.getHeartbeatsHeader()
+      );
+      if (isIndexedDBAvailable()) {
+        expect(heartbeatHeaders).to.include('old-user-agent');
+        expect(heartbeatHeaders).to.include('1969-01-01');
+        expect(heartbeatHeaders).to.include('1969-01-02');
+      }
+      expect(heartbeatHeaders).to.include(USER_AGENT_STRING_2);
+      expect(heartbeatHeaders).to.include('1970-01-04');
+      expect(heartbeatHeaders).to.include(`"version":2`);
+      expect(heartbeatService._heartbeatsCache).to.equal(null);
+      const emptyHeaders = await heartbeatService.getHeartbeatsHeader();
+      expect(emptyHeaders).to.equal('');
+      expect(deleteStub).to.be.called;
+    });
+  });
+});