Use the FID from the server if client FID generation fails

packages/firebase/package.json

@@ -43,7 +43,7 @@
     "@firebase/database": "0.4.6",
     "@firebase/firestore": "1.4.2",
     "@firebase/functions": "0.4.10",
-    "@firebase/installations": "0.1.7",
+    "@firebase/installations": "0.2.0",
     "@firebase/messaging": "0.4.3",
     "@firebase/polyfill": "0.3.14",
     "@firebase/storage": "0.3.4",

packages/installations/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@firebase/installations",
-  "version": "0.1.7",
+  "version": "0.2.0",
   "main": "dist/index.cjs.js",
   "module": "dist/index.esm.js",
   "esm2017": "dist/index.esm2017.js",

packages/installations/src/api/create-installation.test.ts

@@ -58,7 +58,8 @@ describe('createInstallation', () => {
         token:
           'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCeKKF2QT4fwpMeJf36POk6yJV_adQssw5c',
         expiresIn: '604800s'
-      }
+      },
+      fid: FID
     };
     fetchSpy = stub(self, 'fetch');
   });

packages/installations/src/api/create-installation.ts

@@ -55,7 +55,7 @@ export async function createInstallation(
   if (response.ok) {
     const responseValue: CreateInstallationResponse = await response.json();
     const registeredInstallationEntry: RegisteredInstallationEntry = {
-      fid,
+      fid: responseValue.fid,
       registrationStatus: RequestStatus.COMPLETED,
       refreshToken: responseValue.refreshToken,
       authToken: extractAuthTokenInfoFromResponse(responseValue.authToken)

packages/installations/src/helpers/buffer-to-base64-url-safe.test.ts

@@ -28,10 +28,4 @@ describe('bufferToBase64', () => {
       BASE_64_REPRESENTATION
     );
   });
-
-  it('returns a base64 representation of an ArrayBuffer', () => {
-    expect(bufferToBase64UrlSafe(TYPED_ARRAY_REPRESENTATION.buffer)).to.equal(
-      BASE_64_REPRESENTATION
-    );
-  });
 });

packages/installations/src/helpers/buffer-to-base64-url-safe.ts

@@ -15,10 +15,7 @@
  * limitations under the License.
  */
 
-export function bufferToBase64UrlSafe(
-  buffer: ArrayBuffer | Uint8Array
-): string {
-  const array = buffer instanceof Uint8Array ? buffer : new Uint8Array(buffer);
+export function bufferToBase64UrlSafe(array: Uint8Array): string {
   const b64 = btoa(String.fromCharCode(...array));
   return b64.replace(/\+/g, '-').replace(/\//g, '_');
 }

packages/installations/src/helpers/generate-fid.test.ts

@@ -18,7 +18,7 @@
 import { expect } from 'chai';
 import { stub } from 'sinon';
 import '../testing/setup';
-import { generateFid } from './generate-fid';
+import { generateFid, VALID_FID_PATTERN } from './generate-fid';
 
 /** A few random values to generate a FID from. */
 // prettier-ignore
@@ -53,8 +53,6 @@ const EXPECTED_FIDS = [
   'f_____________________'
 ];
 
-const VALID_FID = /^[cdef][A-Za-z0-9_-]{21}$/;
-
 describe('generateFid', () => {
   it('deterministically generates FIDs based on crypto.getRandomValues', () => {
     let randomValueIndex = 0;
@@ -77,7 +75,10 @@ describe('generateFid', () => {
   it('generates valid FIDs', () => {
     for (let i = 0; i < 1000; i++) {
       const fid = generateFid();
-      expect(VALID_FID.test(fid)).to.equal(true, `${fid} is not a valid FID`);
+      expect(VALID_FID_PATTERN.test(fid)).to.equal(
+        true,
+        `${fid} is not a valid FID`
+      );
     }
   });
 
@@ -117,4 +118,11 @@ describe('generateFid', () => {
       });
     }
   }).timeout(30000);
+
+  it('returns an empty string if FID generation fails', () => {
+    stub(crypto, 'getRandomValues').throws();
+
+    const fid = generateFid();
+    expect(fid).to.equal('');
+  });
 });

packages/installations/src/helpers/generate-fid.ts

@@ -17,17 +17,32 @@
 
 import { bufferToBase64UrlSafe } from './buffer-to-base64-url-safe';
 
-/** Generates a new FID using random values from Web Crypto API. */
+export const VALID_FID_PATTERN = /^[cdef][\w-]{21}$/;
+export const INVALID_FID = '';
+
+/**
+ * Generates a new FID using random values from Web Crypto API.
+ * Returns an empty string if FID generation fails for any reason.
+ */
 export function generateFid(): string {
-  // A valid FID has exactly 22 base64 characters, which is 132 bits, or 16.5
-  // bytes. our implementation generates a 17 byte array instead.
-  const fidByteArray = new Uint8Array(17);
-  crypto.getRandomValues(fidByteArray);
+  try {
+    // A valid FID has exactly 22 base64 characters, which is 132 bits, or 16.5
+    // bytes. our implementation generates a 17 byte array instead.
+    const fidByteArray = new Uint8Array(17);
+    const crypto =
+      self.crypto || ((self as unknown) as { msCrypto: Crypto }).msCrypto;
+    crypto.getRandomValues(fidByteArray);
+
+    // Replace the first 4 random bits with the constant FID header of 0b0111.
+    fidByteArray[0] = 0b01110000 + (fidByteArray[0] % 0b00010000);
 
-  // Replace the first 4 random bits with the constant FID header of 0b0111.
-  fidByteArray[0] = 0b01110000 + (fidByteArray[0] % 0b00010000);
+    const fid = encode(fidByteArray);
 
-  return encode(fidByteArray);
+    return VALID_FID_PATTERN.test(fid) ? fid : INVALID_FID;
+  } catch {
+    // FID generation errored
+    return INVALID_FID;
+  }
 }
 
 /** Converts a FID Uint8Array to a base64 string representation. */

packages/installations/src/helpers/get-installation-entry.test.ts

@@ -29,7 +29,7 @@ import { getFakeAppConfig } from '../testing/get-fake-app';
 import '../testing/setup';
 import { ERROR_FACTORY, ErrorCode } from '../util/errors';
 import { sleep } from '../util/sleep';
-import * as fidGenerator from './generate-fid';
+import * as generateFidModule from './generate-fid';
 import { getInstallationEntry } from './get-installation-entry';
 import { get, set } from './idb-manager';
 
@@ -53,7 +53,8 @@ describe('getInstallationEntry', () => {
       async (_, installationEntry): Promise<RegisteredInstallationEntry> => {
         await sleep(100); // Request would take some time
         const registeredInstallationEntry: RegisteredInstallationEntry = {
-          fid: installationEntry.fid,
+          // Returns new FID if client FID is invalid.
+          fid: installationEntry.fid || FID,
           registrationStatus: RequestStatus.COMPLETED,
           refreshToken: 'refreshToken',
           authToken: {
@@ -179,9 +180,10 @@ describe('getInstallationEntry', () => {
     let generateInstallationEntrySpy: SinonStub<[], string>;
 
     beforeEach(() => {
-      generateInstallationEntrySpy = stub(fidGenerator, 'generateFid').returns(
-        FID
-      );
+      generateInstallationEntrySpy = stub(
+        generateFidModule,
+        'generateFid'
+      ).returns(FID);
     });
 
     it('returns a new pending InstallationEntry and triggers createInstallation', async () => {
@@ -255,6 +257,25 @@ describe('getInstallationEntry', () => {
 
       expect(createInstallationSpy).to.be.calledOnce;
     });
+
+    it('waits for the FID from the server if FID generation fails', async () => {
+      clock.restore();
+      // Needed to allow the createInstallation request to complete.
+      clock = useFakeTimers({ shouldAdvanceTime: true });
+
+      // FID generation fails.
+      generateInstallationEntrySpy.returns(generateFidModule.INVALID_FID);
+
+      const getInstallationEntryPromise = getInstallationEntry(appConfig);
+
+      const {
+        installationEntry,
+        registrationPromise
+      } = await getInstallationEntryPromise;
+
+      expect(installationEntry.fid).to.equal(FID);
+      expect(registrationPromise).to.be.undefined;
+    });
   });
 
   describe('when there is an unregistered InstallationEntry in the database', () => {

packages/installations/src/helpers/get-installation-entry.ts

@@ -20,17 +20,18 @@ import { AppConfig } from '../interfaces/app-config';
 import {
   InProgressInstallationEntry,
   InstallationEntry,
-  RequestStatus
+  RequestStatus,
+  RegisteredInstallationEntry
 } from '../interfaces/installation-entry';
 import { PENDING_TIMEOUT_MS } from '../util/constants';
 import { ERROR_FACTORY, ErrorCode, isServerError } from '../util/errors';
 import { sleep } from '../util/sleep';
-import { generateFid } from './generate-fid';
+import { generateFid, INVALID_FID } from './generate-fid';
 import { remove, set, update } from './idb-manager';
 
 export interface InstallationEntryWithRegistrationPromise {
   installationEntry: InstallationEntry;
-  registrationPromise?: Promise<void>;
+  registrationPromise?: Promise<RegisteredInstallationEntry>;
 }
 
 /**
@@ -40,26 +41,33 @@ export interface InstallationEntryWithRegistrationPromise {
 export async function getInstallationEntry(
   appConfig: AppConfig
 ): Promise<InstallationEntryWithRegistrationPromise> {
-  let registrationPromise: Promise<void> | undefined;
+  let registrationPromise: Promise<RegisteredInstallationEntry> | undefined;
+
+  const installationEntry = await update(
+    appConfig,
+    (oldEntry?: InstallationEntry): InstallationEntry => {
+      const installationEntry = updateOrCreateInstallationEntry(oldEntry);
+      const entryWithPromise = triggerRegistrationIfNecessary(
+        appConfig,
+        installationEntry
+      );
+      registrationPromise = entryWithPromise.registrationPromise;
+      return entryWithPromise.installationEntry;
+    }
+  );
+
+  if (installationEntry.fid === INVALID_FID) {
+    // FID generation failed. Waiting for the FID from the server.
+    return { installationEntry: await registrationPromise! };
+  }
 
   return {
-    installationEntry: await update(
-      appConfig,
-      (oldEntry?: InstallationEntry): InstallationEntry => {
-        const installationEntry = updateOrCreateFid(oldEntry);
-        const entryWithPromise = triggerRegistrationIfNecessary(
-          appConfig,
-          installationEntry
-        );
-        registrationPromise = entryWithPromise.registrationPromise;
-        return entryWithPromise.installationEntry;
-      }
-    ),
+    installationEntry,
     registrationPromise
   };
 }
 
-function updateOrCreateFid(
+function updateOrCreateInstallationEntry(
   oldEntry: InstallationEntry | undefined
 ): InstallationEntry {
   const entry: InstallationEntry = oldEntry || {
@@ -124,13 +132,13 @@ function triggerRegistrationIfNecessary(
 async function registerInstallation(
   appConfig: AppConfig,
   installationEntry: InProgressInstallationEntry
-): Promise<void> {
+): Promise<RegisteredInstallationEntry> {
   try {
     const registeredInstallationEntry = await createInstallation(
       appConfig,
       installationEntry
     );
-    await set(appConfig, registeredInstallationEntry);
+    return set(appConfig, registeredInstallationEntry);
   } catch (e) {
     if (isServerError(e) && e.serverCode === 409) {
       // Server returned a "FID can not be used" error.
@@ -148,7 +156,9 @@ async function registerInstallation(
 }
 
 /** Call if FID registration is pending. */
-async function waitUntilFidRegistration(appConfig: AppConfig): Promise<void> {
+async function waitUntilFidRegistration(
+  appConfig: AppConfig
+): Promise<RegisteredInstallationEntry> {
   // Unfortunately, there is no way of reliably observing when a value in
   // IndexedDB changes (yet, see https://github.com/WICG/indexed-db-observers),
   // so we need to poll.
@@ -164,6 +174,8 @@ async function waitUntilFidRegistration(appConfig: AppConfig): Promise<void> {
   if (entry.registrationStatus === RequestStatus.NOT_STARTED) {
     throw ERROR_FACTORY.create(ErrorCode.CREATE_INSTALLATION_FAILED);
   }
+
+  return entry;
 }
 
 /**

packages/installations/src/interfaces/api-response.ts

@@ -18,6 +18,7 @@
 export interface CreateInstallationResponse {
   readonly refreshToken: string;
   readonly authToken: GenerateAuthTokenResponse;
+  readonly fid: string;
 }
 
 export interface GenerateAuthTokenResponse {

packages/performance/package.json

@@ -27,7 +27,7 @@
   },
   "dependencies": {
     "@firebase/logger": "0.1.17",
-    "@firebase/installations": "0.1.7",
+    "@firebase/installations": "0.2.0",
     "@firebase/util": "0.2.20",
     "@firebase/performance-types": "0.0.2",
     "tslib": "1.9.3"