Add environment check to Remote-Config Module (#3623)

.changeset/blue-rice-ring.md

@@ -0,0 +1,6 @@
+---
+"firebase": minor
+"@firebase/remote-config": minor
+---
+
+Issue 2393 - Add environment check to Remote-Config Module

common/api-review/remote-config.api.md

@@ -39,6 +39,9 @@ export function getString(remoteConfig: RemoteConfig, key: string): string;
 // @public
 export function getValue(remoteConfig: RemoteConfig, key: string): Value;
 
+// @public
+export function isSupported(): Promise<boolean>;
+
 // @public
 export type LogLevel = 'debug' | 'error' | 'silent';
 

packages/firebase/compat/index.d.ts

@@ -2031,6 +2031,16 @@ declare namespace firebase.remoteConfig {
    * Defines levels of Remote Config logging.
    */
   export type LogLevel = 'debug' | 'error' | 'silent';
+  /**
+   * This method provides two different checks:
+   *
+   * 1. Check if IndexedDB exists in the browser environment.
+   * 2. Check if the current browser context allows IndexedDB `open()` calls.
+   *
+   * It returns a `Promise` which resolves to true if a {@link RemoteConfig} instance
+   * can be initialized in this environment, or false if it cannot.
+   */
+  export function isSupported(): Promise<boolean>;
 }
 
 declare namespace firebase.functions {
@@ -4623,13 +4633,14 @@ declare namespace firebase.auth {
    *     instance must be initialized with an API key, otherwise an error will be
    *     thrown.
    */
-  class RecaptchaVerifier extends RecaptchaVerifier_Instance { }
+  class RecaptchaVerifier extends RecaptchaVerifier_Instance {}
   /**
    * @webonly
    * @hidden
    */
   class RecaptchaVerifier_Instance
-    implements firebase.auth.ApplicationVerifier {
+    implements firebase.auth.ApplicationVerifier
+  {
     constructor(
       container: any | string,
       parameters?: Object | null,
@@ -7310,7 +7321,7 @@ declare namespace firebase.database {
 
   interface ThenableReference
     extends firebase.database.Reference,
-    Pick<Promise<Reference>, 'then' | 'catch'> { }
+      Pick<Promise<Reference>, 'then' | 'catch'> {}
 
   /**
    * Logs debugging information to the console.
@@ -7690,7 +7701,9 @@ declare namespace firebase.storage {
      *     resolves with the full updated metadata or rejects if the updated failed,
      *     including if the object did not exist.
      */
-    updateMetadata(metadata: firebase.storage.SettableMetadata): Promise<FullMetadata>;
+    updateMetadata(
+      metadata: firebase.storage.SettableMetadata
+    ): Promise<FullMetadata>;
     /**
      * List all items (files) and prefixes (folders) under this storage reference.
      *
@@ -9520,7 +9533,7 @@ declare namespace firebase.firestore {
    */
   export class QueryDocumentSnapshot<
     T = DocumentData
-    > extends DocumentSnapshot<T> {
+  > extends DocumentSnapshot<T> {
     private constructor();
 
     /**

packages/remote-config-compat/src/index.ts

@@ -22,7 +22,7 @@ import {
   ComponentType,
   InstanceFactoryOptions
 } from '@firebase/component';
-import { RemoteConfigCompatImpl } from './remoteConfig';
+import { RemoteConfigCompatImpl, isSupported } from './remoteConfig';
 import { name as packageName, version } from '../package.json';
 import { RemoteConfig as RemoteConfigCompat } from '@firebase/remote-config-types';
 
@@ -34,7 +34,9 @@ function registerRemoteConfigCompat(
       'remoteConfig-compat',
       remoteConfigFactory,
       ComponentType.PUBLIC
-    ).setMultipleInstances(true)
+    )
+      .setMultipleInstances(true)
+      .setServiceProps({ isSupported })
   );
 
   firebaseInstance.registerVersion(packageName, version);

packages/remote-config-compat/src/remoteConfig.ts

@@ -34,11 +34,15 @@ import {
   getBoolean,
   getNumber,
   getString,
-  getValue
+  getValue,
+  isSupported
 } from '@firebase/remote-config';
 
+export { isSupported };
+
 export class RemoteConfigCompatImpl
-  implements RemoteConfigCompat, _FirebaseService {
+  implements RemoteConfigCompat, _FirebaseService
+{
   constructor(public app: FirebaseApp, readonly _delegate: RemoteConfig) {}
 
   get defaultConfig(): { [key: string]: string | number | boolean } {

packages/remote-config/src/api2.ts

@@ -17,7 +17,11 @@
 
 import { RemoteConfig } from './public_types';
 import { activate, fetchConfig } from './api';
-import { getModularInstance } from '@firebase/util';
+import {
+  getModularInstance,
+  isIndexedDBAvailable,
+  validateIndexedDBOpenable
+} from '@firebase/util';
 
 // This API is put in a separate file, so we can stub fetchConfig and activate in tests.
 // It's not possible to stub standalone functions from the same module.
@@ -39,3 +43,26 @@ export async function fetchAndActivate(
   await fetchConfig(remoteConfig);
   return activate(remoteConfig);
 }
+
+/**
+ * This method provides two different checks:
+ *
+ * 1. Check if IndexedDB exists in the browser environment.
+ * 2. Check if the current browser context allows IndexedDB `open()` calls.
+ *
+ * @returns A `Promise` which resolves to true if a {@link RemoteConfig} instance
+ * can be initialized in this environment, or false if it cannot.
+ * @public
+ */
+export async function isSupported(): Promise<boolean> {
+  if (!isIndexedDBAvailable()) {
+    return false;
+  }
+
+  try {
+    const isDBOpenable: boolean = await validateIndexedDBOpenable();
+    return isDBOpenable;
+  } catch (error) {
+    return false;
+  }
+}

packages/remote-config/src/errors.ts

@@ -30,7 +30,8 @@ export const enum ErrorCode {
   FETCH_TIMEOUT = 'fetch-timeout',
   FETCH_THROTTLE = 'fetch-throttle',
   FETCH_PARSE = 'fetch-client-parse',
-  FETCH_STATUS = 'fetch-status'
+  FETCH_STATUS = 'fetch-status',
+  INDEXED_DB_UNAVAILABLE = 'indexed-db-unavailable'
 }
 
 const ERROR_DESCRIPTION_MAP: { readonly [key in ErrorCode]: string } = {
@@ -64,7 +65,9 @@ const ERROR_DESCRIPTION_MAP: { readonly [key in ErrorCode]: string } = {
     'Fetch client could not parse response.' +
     ' Original error: {$originalErrorMessage}.',
   [ErrorCode.FETCH_STATUS]:
-    'Fetch server returned an HTTP error status. HTTP status: {$httpStatus}.'
+    'Fetch server returned an HTTP error status. HTTP status: {$httpStatus}.',
+  [ErrorCode.INDEXED_DB_UNAVAILABLE]:
+    'Indexed DB is not supported by current browser'
 };
 
 // Note this is effectively a type system binding a code to params. This approach overlaps with the

packages/remote-config/src/register.ts

@@ -19,6 +19,7 @@ import {
   registerVersion,
   SDK_VERSION
 } from '@firebase/app';
+import { isIndexedDBAvailable } from '@firebase/util';
 import {
   Component,
   ComponentType,
@@ -68,7 +69,10 @@ export function registerRemoteConfig(): void {
     if (typeof window === 'undefined') {
       throw ERROR_FACTORY.create(ErrorCode.REGISTRATION_WINDOW);
     }
-
+    // Guards against the SDK being used when indexedDB is not available.
+    if (!isIndexedDBAvailable()) {
+      throw ERROR_FACTORY.create(ErrorCode.INDEXED_DB_UNAVAILABLE);
+    }
     // Normalizes optional inputs.
     const { projectId, apiKey, appId } = app.options;
     if (!projectId) {

packages/remote-config/src/storage/storage.ts

@@ -75,28 +75,36 @@ type ProjectNamespaceKeyFieldValue =
 // Visible for testing.
 export function openDatabase(): Promise<IDBDatabase> {
   return new Promise((resolve, reject) => {
-    const request = indexedDB.open(DB_NAME, DB_VERSION);
-    request.onerror = event => {
-      reject(toFirebaseError(event, ErrorCode.STORAGE_OPEN));
-    };
-    request.onsuccess = event => {
-      resolve((event.target as IDBOpenDBRequest).result);
-    };
-    request.onupgradeneeded = event => {
-      const db = (event.target as IDBOpenDBRequest).result;
+    try {
+      const request = indexedDB.open(DB_NAME, DB_VERSION);
+      request.onerror = event => {
+        reject(toFirebaseError(event, ErrorCode.STORAGE_OPEN));
+      };
+      request.onsuccess = event => {
+        resolve((event.target as IDBOpenDBRequest).result);
+      };
+      request.onupgradeneeded = event => {
+        const db = (event.target as IDBOpenDBRequest).result;
 
-      // We don't use 'break' in this switch statement, the fall-through
-      // behavior is what we want, because if there are multiple versions between
-      // the old version and the current version, we want ALL the migrations
-      // that correspond to those versions to run, not only the last one.
-      // eslint-disable-next-line default-case
-      switch (event.oldVersion) {
-        case 0:
-          db.createObjectStore(APP_NAMESPACE_STORE, {
-            keyPath: 'compositeKey'
-          });
-      }
-    };
+        // We don't use 'break' in this switch statement, the fall-through
+        // behavior is what we want, because if there are multiple versions between
+        // the old version and the current version, we want ALL the migrations
+        // that correspond to those versions to run, not only the last one.
+        // eslint-disable-next-line default-case
+        switch (event.oldVersion) {
+          case 0:
+            db.createObjectStore(APP_NAMESPACE_STORE, {
+              keyPath: 'compositeKey'
+            });
+        }
+      };
+    } catch (error) {
+      reject(
+        ERROR_FACTORY.create(ErrorCode.STORAGE_OPEN, {
+          originalErrorMessage: error
+        })
+      );
+    }
   });
 }