fix(other): add api for persistence via Async Storage

packages/app/lib/index.d.ts

@@ -158,6 +158,36 @@ export namespace ReactNativeFirebase {
     utils(): Utils.Module;
   }
 
+  /**
+   * Interface for a supplied `AsyncStorage`.
+   */
+  export interface ReactNativeAsyncStorage {
+    /**
+     * Persist an item in storage.
+     *
+     * @param key - storage key.
+     * @param value - storage value.
+     */
+    // eslint-disable-next-line @typescript-eslint/ban-types
+    setItem: Function;
+    /**
+     * Retrieve an item from storage.
+     *
+     * @param key - storage key.
+     */
+    // eslint-disable-next-line @typescript-eslint/ban-types
+    getItem: Function;
+    /**
+     * Remove an item from storage.
+     *
+     * @param key - storage key.
+     */
+    // eslint-disable-next-line @typescript-eslint/ban-types
+    removeItem: Function;
+
+    [key: string]: any;
+  }
+
   export interface Module {
     /**
      * Create (and initialize) a FirebaseApp.
@@ -201,6 +231,14 @@ export namespace ReactNativeFirebase {
      */
     setLogLevel(logLevel: LogLevelString): void;
 
+    /**
+     * The `AsyncStorage` implementation to use for persisting data on 'Other' platforms.
+     * If not specified, in memory persistence is used.
+     *
+     * This is required if you want to persist things like Auth sessions, Analytics device IDs, etc.
+     */
+    setReactNativeAsyncStorage(asyncStorage: ReactNativeAsyncStorage): void;
+
     /**
      * A (read-only) array of all the initialized Apps.
      */

packages/app/lib/internal/asyncStorage.js

@@ -0,0 +1,47 @@
+export const memoryStorage = new Map();
+
+export const prefix = '@react-native-firebase:';
+
+const asyncStorageMemory = {
+  setItem(key, value) {
+    memoryStorage.set(key, value);
+    return Promise.resolve();
+  },
+  getItem(key) {
+    const hasValue = memoryStorage.has(key);
+    if (hasValue) {
+      return Promise.resolve(memoryStorage.get(key));
+    }
+    return Promise.resolve(null);
+  },
+  removeItem: function (key) {
+    memoryStorage.delete(key);
+    return Promise.resolve();
+  },
+};
+
+let asyncStorage = asyncStorageMemory;
+
+export async function getReactNativeAsyncStorageInternal() {
+  return asyncStorage;
+}
+
+export function setReactNativeAsyncStorageInternal(asyncStorageInstance) {
+  asyncStorage = asyncStorageInstance || asyncStorageMemory;
+}
+
+export function isMemoryStorage() {
+  return asyncStorage === asyncStorageMemory;
+}
+
+export async function setItem(key, value) {
+  return await asyncStorage.setItem(prefix + key, value);
+}
+
+export async function getItem(key) {
+  return await asyncStorage.getItem(prefix + key);
+}
+
+export async function removeItem(key) {
+  return await asyncStorage.removeItem(prefix + key);
+}

packages/app/lib/internal/registry/app.js

@@ -20,11 +20,13 @@ import {
   isOther,
   isNull,
   isObject,
+  isFunction,
   isString,
   isUndefined,
 } from '@react-native-firebase/app/lib/common';
 import FirebaseApp from '../../FirebaseApp';
 import { DEFAULT_APP_NAME } from '../constants';
+import { setReactNativeAsyncStorageInternal } from '../asyncStorage';
 import { getAppModule } from './nativeModule';
 
 const APP_REGISTRY = {};
@@ -172,15 +174,15 @@ export function initializeApp(options = {}, configOrName) {
     );
   }
 
-  const app = new FirebaseApp(options, { name }, false, deleteApp.bind(null, name, true));
+  const app = new FirebaseApp(options, appConfig, false, deleteApp.bind(null, name, true));
 
   // Note these initialization actions with side effects are performed prior to knowledge of
   // successful initialization in the native code. Native code *may* throw an error.
   APP_REGISTRY[name] = app;
   onAppCreateFn(APP_REGISTRY[name]);
 
   return getAppModule()
-    .initializeApp(options, { name })
+    .initializeApp(options, appConfig)
     .then(() => {
       app._initialized = true;
       return app;
@@ -207,6 +209,32 @@ export function setLogLevel(logLevel) {
   }
 }
 
+export function setReactNativeAsyncStorage(asyncStorage) {
+  if (!isObject(asyncStorage)) {
+    throw new Error("firebase.setReactNativeAsyncStorage(*) 'asyncStorage' must be an object.");
+  }
+
+  if (!isFunction(asyncStorage.setItem)) {
+    throw new Error(
+      "firebase.setReactNativeAsyncStorage(*) 'asyncStorage.setItem' must be a function.",
+    );
+  }
+
+  if (!isFunction(asyncStorage.getItem)) {
+    throw new Error(
+      "firebase.setReactNativeAsyncStorage(*) 'asyncStorage.getItem' must be a function.",
+    );
+  }
+
+  if (!isFunction(asyncStorage.removeItem)) {
+    throw new Error(
+      "firebase.setReactNativeAsyncStorage(*) 'asyncStorage.removeItem' must be a function.",
+    );
+  }
+
+  setReactNativeAsyncStorageInternal(asyncStorage);
+}
+
 /**
  *
  */

packages/app/lib/internal/registry/namespace.js

@@ -25,6 +25,7 @@ import {
   getApps,
   initializeApp,
   setLogLevel,
+  setReactNativeAsyncStorage,
   setOnAppCreate,
   setOnAppDestroy,
 } from './app';
@@ -241,6 +242,7 @@ export function firebaseAppModuleProxy(app, moduleNamespace) {
 export function createFirebaseRoot() {
   FIREBASE_ROOT = {
     initializeApp,
+    setReactNativeAsyncStorage,
     get app() {
       return getApp;
     },