Static Loading of Service Namespaces (#106)

* Getting rid of the monkeypatching code

* Implemented static on-demand loading for all services except RTDB

* Using Object.assign() instead of _.assign()

Author: hiranya911

package.json

@@ -56,8 +56,7 @@
     "@types/node": "^8.0.32",
     "faye-websocket": "0.9.3",
     "jsonwebtoken": "7.1.9",
-    "node-forge": "0.7.1",
-    "lodash": "^4.6.1"
+    "node-forge": "0.7.1"
   },
   "devDependencies": {
     "@types/chai": "^3.4.34",
@@ -84,6 +83,7 @@
     "gulp-replace": "^0.5.4",
     "gulp-tslint": "^6.0.2",
     "gulp-typescript": "^3.1.2",
+    "lodash": "^4.6.1",
     "merge2": "^1.0.2",
     "mocha": "^3.5.0",
     "nock": "^8.0.0",

src/auth/auth.ts

@@ -28,7 +28,7 @@ import * as validator from '../utils/validator';
 /**
  * Internals of an Auth instance.
  */
-export class AuthInternals implements FirebaseServiceInternalsInterface {
+class AuthInternals implements FirebaseServiceInternalsInterface {
   /**
    * Deletes the service and its associated resources.
    *
@@ -51,7 +51,7 @@ export interface ListUsersResult {
 /**
  * Auth service bound to the provided app.
  */
-class Auth implements FirebaseServiceInterface {
+export class Auth implements FirebaseServiceInterface {
   public INTERNAL: AuthInternals = new AuthInternals();
 
   private app_: FirebaseApp;
@@ -286,8 +286,3 @@ class Auth implements FirebaseServiceInterface {
       });
   };
 };
-
-
-export {
-  Auth,
-}

src/auth/register-auth.ts

@@ -22,7 +22,11 @@ import {FirebaseServiceInterface} from './firebase-service';
 import {FirebaseNamespaceInternals} from './firebase-namespace';
 import {AppErrorCodes, FirebaseAppError} from './utils/error';
 import {Firestore} from '@google-cloud/firestore';
+import {FirestoreService} from './firestore/firestore';
 
+import {Auth} from './auth/auth';
+import {Messaging} from './messaging/messaging';
+import {Storage} from './storage/storage';
 
 /**
  * Type representing a callback which is called every time an app lifecycle event occurs.
@@ -276,16 +280,14 @@ export class FirebaseApp {
   }
 
   /**
-   * Firebase services available off of a FirebaseApp instance. These are monkey-patched via
-   * registerService(), but we need to include a dummy implementation to get TypeScript to
-   * compile it without errors.
+   * Returns the Auth service instance associated with this app.
+   * 
+   * @return {Auth} The Auth service instance of this app.
    */
-  /* istanbul ignore next */
-  public auth(): FirebaseServiceInterface {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase auth() service has not been registered.',
-    );
+  public auth(): Auth {
+    return this.ensureService_('auth', () => {
+      return new Auth(this);
+    });
   }
 
   /* istanbul ignore next */
@@ -296,28 +298,33 @@ export class FirebaseApp {
     );
   }
 
-  /* istanbul ignore next */
-  public messaging(): FirebaseServiceInterface {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase messaging() service has not been registered.',
-    );
+  /**
+   * Returns the Messaging service instance associated with this app.
+   * 
+   * @return {Messaging} The Messaging service instance of this app.
+   */
+  public messaging(): Messaging {
+    return this.ensureService_('messaging', () => {
+      return new Messaging(this);
+    });
   }
 
-  /* istanbul ignore next */
-  public storage(): FirebaseServiceInterface {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase storage() service has not been registered.',
-    );
+  /**
+   * Returns the Storage service instance associated with this app.
+   * 
+   * @return {Storage} The Storage service instance of this app.
+   */
+  public storage(): Storage {
+    return this.ensureService_('storage', () => {
+      return new Storage(this);
+    });
   }
 
-  /* istanbul ignore next */
   public firestore(): Firestore {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase firestore() service has not been registered.',
-    );
+    let service: FirestoreService = this.ensureService_('firestore', () => {
+      return new FirestoreService(this);
+    });
+    return service.client;
   }
 
   /**
@@ -359,9 +366,22 @@ export class FirebaseApp {
     });
   }
 
+  private ensureService_<T extends FirebaseServiceInterface>(serviceName: string, initializer: () => T): T {
+    this.checkDestroyed_();
+
+    let service: T;
+    if (serviceName in this.services_) {
+      service = this.services_[serviceName] as T;
+    } else {
+      service = initializer();
+      this.services_[serviceName] = service;
+    }
+    return service;
+  }
+
   /**
    * Returns the service instance associated with this FirebaseApp instance (creating it on demand
-   * if needed).
+   * if needed). This is used for looking up monkeypatched service instances.
    *
    * @param {string} serviceName The name of the service instance to return.
    * @return {FirebaseServiceInterface} The service instance with the provided name.

src/firebase-app.ts

@@ -26,15 +26,20 @@ import {
 } from './auth/credential';
 import {Firestore} from '@google-cloud/firestore';
 
+import {Auth} from './auth/auth';
+import {Messaging} from './messaging/messaging';
+import {Storage} from './storage/storage';
+
 const DEFAULT_APP_NAME = '[DEFAULT]';
 
 let globalAppDefaultCred: ApplicationDefaultCredential;
 let globalCertCreds: { [key: string]: CertCredential } = {};
 let globalRefreshTokenCreds: { [key: string]: RefreshTokenCredential } = {};
 
 
-export interface FirebaseServiceNamespace <T extends FirebaseServiceInterface> {
+export interface FirebaseServiceNamespace <T> {
   (app?: FirebaseApp): T;
+  [key: string]: any;
 }
 
 
@@ -273,16 +278,15 @@ export class FirebaseNamespace {
   }
 
   /**
-   * Firebase services available off of a FirebaseNamespace instance. These are monkey-patched via
-   * registerService(), but we need to include a dummy implementation to get TypeScript to
-   * compile it without errors.
+   * Gets the `Auth` service namespace. The returned namespace can be used to get the
+   * `Auth` service for the default app or an explicitly specified app.
    */
-  /* istanbul ignore next */
-  public auth(): FirebaseServiceInterface {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase auth() service has not been registered.',
-    );
+  get auth(): FirebaseServiceNamespace<Auth> {
+    const ns: FirebaseNamespace = this;
+    let fn: FirebaseServiceNamespace<Auth> = (app?: FirebaseApp) => {
+      return ns.ensureApp(app).auth();
+    };
+    return Object.assign(fn, {Auth});
   }
 
   /* istanbul ignore next */
@@ -293,28 +297,40 @@ export class FirebaseNamespace {
     );
   }
 
-  /* istanbul ignore next */
-  public messaging(): FirebaseServiceInterface {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase messaging() service has not been registered.',
-    );
+  /**
+   * Gets the `Messaging` service namespace. The returned namespace can be used to get the
+   * `Messaging` service for the default app or an explicitly specified app.
+   */
+  get messaging(): FirebaseServiceNamespace<Messaging> {
+    const ns: FirebaseNamespace = this;
+    let fn: FirebaseServiceNamespace<Messaging> = (app?: FirebaseApp) => {
+      return ns.ensureApp(app).messaging();
+    };
+    return Object.assign(fn, {Messaging});
   }
 
-  /* istanbul ignore next */
-  public storage(): FirebaseServiceInterface {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase storage() service has not been registered.',
-    );
+  /**
+   * Gets the `Storage` service namespace. The returned namespace can be used to get the
+   * `Storage` service for the default app or an explicitly specified app.
+   */
+  get storage(): FirebaseServiceNamespace<Storage> {
+    const ns: FirebaseNamespace = this;
+    let fn: FirebaseServiceNamespace<Storage> = (app?: FirebaseApp) => {
+      return ns.ensureApp(app).storage();
+    };
+    return Object.assign(fn, {Storage});
   }
 
-  /* istanbul ignore next */
-  public firestore(): Firestore {
-    throw new FirebaseAppError(
-      AppErrorCodes.INTERNAL_ERROR,
-      'INTERNAL ASSERT FAILED: Firebase firestore() service has not been registered.',
-    );
+  /**
+   * Gets the `Firestore` service namespace. The returned namespace can be used to get the
+   * `Firestore` service for the default app or an explicitly specified app.
+   */
+  get firestore(): FirebaseServiceNamespace<Firestore> {
+    const ns: FirebaseNamespace = this;
+    let fn: FirebaseServiceNamespace<Firestore> = (app?: FirebaseApp) => {
+      return ns.ensureApp(app).firestore();
+    };
+    return Object.assign(fn, require('@google-cloud/firestore'));
   }
 
   /**
@@ -348,4 +364,11 @@ export class FirebaseNamespace {
   public get apps(): FirebaseApp[] {
     return this.INTERNAL.apps;
   }
+
+  private ensureApp(app?: FirebaseApp): FirebaseApp {
+    if (typeof app === 'undefined') {
+      app = this.app();
+    }
+    return app;
+  }
 }

src/firebase-namespace.ts

@@ -38,6 +38,31 @@ class FirestoreInternals implements FirebaseServiceInternalsInterface {
   }
 }
 
+export class FirestoreService implements FirebaseServiceInterface {
+  public INTERNAL: FirestoreInternals = new FirestoreInternals();
+
+  private appInternal: FirebaseApp;
+  private firestoreClient: Firestore;
+
+  constructor(app: FirebaseApp) {
+    this.firestoreClient = initFirestore(app);
+    this.appInternal = app;
+  }
+
+  /**
+   * Returns the app associated with this Storage instance.
+   *
+   * @return {FirebaseApp} The app associated with this Storage instance.
+   */
+  get app(): FirebaseApp {
+    return this.appInternal;
+  }
+
+  get client(): Firestore {
+    return this.firestoreClient;
+  }
+}
+
 function initFirestore(app: FirebaseApp): Firestore {
   if (!validator.isNonNullObject(app) || !('options' in app)) {
     throw new FirebaseFirestoreError({
@@ -88,18 +113,3 @@ function initFirestore(app: FirebaseApp): Firestore {
   }
   return new Firestore(options);
 }
-
-/**
- * Creates a new Firestore service instance for the given FirebaseApp.
- *
- * @param {FirebaseApp} app The App for this Firestore service.
- * @return {FirebaseServiceInterface} A Firestore service instance.
- */
-export function initFirestoreService(app: FirebaseApp): FirebaseServiceInterface {
-  let firestore: any = initFirestore(app);
-
-  // Extend the Firestore client object so it implements FirebaseServiceInterface.
-  utils.addReadonlyGetter(firestore, 'app', app);
-  firestore.INTERNAL = new FirestoreInternals();
-  return firestore;
-}