Using our subject/cache to fix the init race I introduced (#218)

* Using our subject/cache to fix the init race I introduced with the refactor

* Naming

* Await init on non-contextual app, if one is passed

* void | Promise<any> better describes the contract

* Global cache and test

reactfire/firebaseApp/index.tsx

@@ -6,7 +6,7 @@ export * from './sdk';
 type FirebaseAppContextValue = firebase.app.App;
 
 // INVESTIGATE I don't like magic strings, can we have export this in js-sdk?
-export const DEFAULT_APP_NAME = '[DEFAULT]';
+const DEFAULT_APP_NAME = '[DEFAULT]';
 
 const FirebaseAppContext = React.createContext<
   FirebaseAppContextValue | undefined

reactfire/firebaseApp/sdk.tsx

@@ -1,6 +1,7 @@
-import { DEFAULT_APP_NAME } from '../index';
 import { useFirebaseApp } from '.';
 import * as firebase from 'firebase/app';
+import { Observable } from 'rxjs';
+import { preloadObservable } from '../useObservable';
 
 type ComponentName =
   | 'analytics'
@@ -62,17 +63,19 @@ function proxyComponent(
   componentName: ComponentName
 ): FirebaseNamespaceComponent {
   let contextualApp: App | undefined;
-  const useComponent = () => {
+  const useComponent = (app?: App) => {
     contextualApp = useFirebaseApp();
-    if (!firebase[componentName]) {
-      throw importSDK(componentName);
+    const sdkSubject = preload(componentName, app || contextualApp);
+    if (!sdkSubject.hasValue) {
+      throw sdkSubject.firstEmission;
     }
+    sdkSubject.value; // get value to throw if there's an error
     return firebase[componentName];
   };
   return new Proxy(useComponent, {
     get: (target, p) => target()[p],
     apply: (target, _this, args) => {
-      const component = target().bind(_this);
+      const component = target(args[0]).bind(_this);
       // If they don't pass an app, assume the app in context rather than [DEFAULT]
       if (!args[0]) {
         args[0] = contextualApp;
@@ -102,94 +105,100 @@ export const performance = usePerformance;
 export const remoteConfig = useRemoteConfig;
 export const storage = useStorage;
 
-function preload(
+function preloadFactory(
   componentName: 'auth'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['auth']) => any
+  settingsCallback?: (instanceFactory: App['auth']) => void | Promise<any>
 ) => Promise<App['auth']>;
-function preload(
+function preloadFactory(
   componentName: 'analytics'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['analytics']) => any
+  settingsCallback?: (instanceFactory: App['analytics']) => void | Promise<any>
 ) => Promise<App['analytics']>;
-function preload(
+function preloadFactory(
   componentName: 'database'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['database']) => any
+  settingsCallback?: (instanceFactory: App['database']) => void | Promise<any>
 ) => Promise<App['database']>;
-function preload(
+function preloadFactory(
   componentName: 'firestore'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['firestore']) => any
+  settingsCallback?: (instanceFactory: App['firestore']) => void | Promise<any>
 ) => Promise<App['firestore']>;
-function preload(
+function preloadFactory(
   componentName: 'functions'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['functions']) => any
+  settingsCallback?: (instanceFactory: App['functions']) => void | Promise<any>
 ) => Promise<App['functions']>;
-function preload(
+function preloadFactory(
   componentName: 'messaging'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['messaging']) => any
+  settingsCallback?: (instanceFactory: App['messaging']) => void | Promise<any>
 ) => Promise<App['messaging']>;
-function preload(
+function preloadFactory(
   componentName: 'performance'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['performance']) => any
+  settingsCallback?: (instanceFactory: App['performance']) => void | Promise<any>
 ) => Promise<App['performance']>;
-function preload(
+function preloadFactory(
   componentName: 'remoteConfig'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['remoteConfig']) => any
+  settingsCallback?: (instanceFactory: App['remoteConfig']) => void | Promise<any>
 ) => Promise<App['remoteConfig']>;
-function preload(
+function preloadFactory(
   componentName: 'storage'
 ): (
   firebaseApp?: App,
-  settingsCallback?: (instanceFactory: App['storage']) => any
+  settingsCallback?: (instanceFactory: App['storage']) => void | Promise<any>
 ) => Promise<App['storage']>;
-function preload(componentName: ComponentName) {
-  return async (
+function preloadFactory(componentName: ComponentName) {
+  return (
     firebaseApp?: App,
     settingsCallback?: (instanceFactory: FirebaseInstanceFactory) => any
-  ) => {
-    const app = firebaseApp || useFirebaseApp();
-    const initialized = !!app[componentName];
-    if (!initialized) {
-      await importSDK(componentName);
-    }
-    const instanceFactory = app[componentName].bind(
-      app
-    ) as FirebaseInstanceFactory;
-    if (initialized) {
-      if (settingsCallback) {
-        console.warn(
-          `${componentName} was already initialized on ${
-            app.name == DEFAULT_APP_NAME ? 'the default app' : app.name
-          }, ignoring settingsCallback`
-        );
-      }
-    } else if (settingsCallback) {
-      await Promise.resolve(settingsCallback(instanceFactory));
-    }
-    return instanceFactory;
-  };
+  ) => preload(componentName, firebaseApp, settingsCallback).toPromise();
 }
 
-export const preloadAuth = preload('auth');
-export const preloadAnalytics = preload('analytics');
-export const preloadDatabase = preload('database');
-export const preloadFirestore = preload('firestore');
-export const preloadFunctions = preload('functions');
-export const preloadMessaging = preload('messaging');
-export const preloadPerformance = preload('performance');
-export const preloadRemoteConfig = preload('remoteConfig');
-export const preloadStorage = preload('storage');
+function preload(
+  componentName: ComponentName,
+  firebaseApp?: App,
+  settingsCallback: (instanceFactory: FirebaseInstanceFactory) => any = () => {}
+) {
+  const app = firebaseApp || useFirebaseApp();
+  return preloadObservable(
+    new Observable(emitter => {
+      importSDK(componentName)
+        .then(() => {
+          const instanceFactory = app[componentName].bind(
+            app
+          ) as FirebaseInstanceFactory;
+          Promise.resolve(settingsCallback(instanceFactory)).then(() => {
+            emitter.next(instanceFactory);
+            emitter.complete();
+          });
+        })
+        .catch(e => {
+          emitter.error(e);
+          emitter.complete();
+        });
+    }),
+    `firebase-sdk:${componentName}:${app.name}`
+  );
+}
+
+export const preloadAuth = preloadFactory('auth');
+export const preloadAnalytics = preloadFactory('analytics');
+export const preloadDatabase = preloadFactory('database');
+export const preloadFirestore = preloadFactory('firestore');
+export const preloadFunctions = preloadFactory('functions');
+export const preloadMessaging = preloadFactory('messaging');
+export const preloadPerformance = preloadFactory('performance');
+export const preloadRemoteConfig = preloadFactory('remoteConfig');
+export const preloadStorage = preloadFactory('storage');

reactfire/firestore/firestore.test.tsx

@@ -10,9 +10,11 @@ import {
   useFirestoreCollectionData,
   useFirestoreDocData,
   useFirestoreDocDataOnce,
-  useFirestoreDocOnce
+  useFirestoreDocOnce,
+  useFirestore
 } from '..';
 import { firestore } from 'firebase/app';
+import { preloadFirestore } from '../firebaseApp';
 
 describe('Firestore', () => {
   let app: import('firebase').app.App;
@@ -41,6 +43,48 @@ describe('Firestore', () => {
       .add({ a: 'hello' });
   });
 
+  describe('useFirestore', () => {
+
+    it('awaits the preloadFirestore setup', async () => {
+      const app2 = firebase.initializeTestApp({
+        projectId: '123456',
+        databaseName: 'my-database',
+        auth: { uid: 'alice' }
+      });
+
+      let firestore: firebase.firestore.Firestore;
+      let preloadResolved = false;
+      let preloadResolve: (v?: unknown) => void;
+      preloadFirestore(app2, () => new Promise(resolve => preloadResolve = resolve)).then(() => preloadResolved = true);
+
+      const Firestore = () => {
+        const firestore = useFirestore(app2);
+        return (
+          <div data-testid="success"></div>
+        );
+      };
+      const { getByTestId } = render(
+        <FirebaseAppProvider firebase={app2}>
+          <React.Suspense fallback={<h1 data-testid="fallback">Fallback</h1>}>
+            <Firestore />
+          </React.Suspense>
+        </FirebaseAppProvider>
+      );
+
+      await waitForElement(() => getByTestId('fallback'));
+      expect(preloadResolved).toEqual(false);
+
+      await waitForElement(() => getByTestId('success')).then(() => fail('expected throw')).catch(() => {});
+      expect(preloadResolved).toEqual(false);
+
+      preloadResolve();
+
+      await waitForElement(() => getByTestId('success'));
+      expect(preloadResolved).toEqual(true);
+
+    });
+  });
+
   describe('useFirestoreDoc', () => {
     it('can get a Firestore document [TEST REQUIRES EMULATOR]', async () => {
       const mockData = { a: 'hello' };

reactfire/useObservable/index.ts

@@ -2,8 +2,22 @@ import * as React from 'react';
 import { Observable } from 'rxjs';
 import { SuspenseSubject } from './SuspenseSubject';
 
+const globalThis = function() {
+  if (typeof self !== 'undefined') { return self; }
+  if (typeof window !== 'undefined') { return window; }
+  if (typeof global !== 'undefined') { return global; }
+  throw new Error('unable to locate global object');
+}();
+
+const PRELOADED_OBSERVABLES = '_reactFirePreloadedObservables';
 const DEFAULT_TIMEOUT = 30_000;
-const preloadedObservables = new Map<string, SuspenseSubject<unknown>>();
+
+// Since we're side-effect free, we need to ensure our observable cache is global
+const preloadedObservables = globalThis[PRELOADED_OBSERVABLES] || new Map<string, SuspenseSubject<unknown>>();
+
+if (!globalThis[PRELOADED_OBSERVABLES]) {
+  globalThis[PRELOADED_OBSERVABLES] = preloadedObservables;
+}
 
 // Starts listening to an Observable.
 // Call this once you know you're going to render a

sample/package.json

@@ -5,6 +5,7 @@
   "dependencies": {
     "@types/jest": "^24.9.0",
     "firebase": "^7.9.1",
+    "js-levenshtein": "^1.1.6",
     "react": "0.0.0-experimental-5de5b6150",
     "react-dom": "0.0.0-experimental-5de5b6150",
     "react-firebaseui": "^4.0.0",

yarn.lock

@@ -7723,6 +7723,11 @@ join-path@^1.1.1:
     url-join "0.0.1"
     valid-url "^1"
 
+js-levenshtein@^1.1.6:
+  version "1.1.6"
+  resolved "https://registry.yarnpkg.com/js-levenshtein/-/js-levenshtein-1.1.6.tgz#c6cee58eb3550372df8deb85fad5ce66ce01d59d"
+  integrity sha512-X2BB11YZtrRqY4EnQcLX5Rh373zbK4alC1FW7D7MBhL2gtcC17cTnr6DmfHZeS0s2rTHjUTMMHfG7gO8SSdw+g==
+
 "js-tokens@^3.0.0 || ^4.0.0", js-tokens@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-4.0.0.tgz#19203fb59991df98e3a287050d4647cdeaf32499"