Implemented Facebook Login without the SDK. Here is the login flow:

You click the Facebook Login button and a request is send to the server to get the redirect_uri to the Facebook login page (the user is redirected when the redirect_uri is returned). Upon entering credentials and giving consent to the application, the user gets redirected back to the app with queryParams in the url containing a code which is then used to obtain an access_token from Facebook. This access_token is returned to the client and the client sends a request with it to the server to invoke the passport-facebook-token strategy and handle the user.

package.json

@@ -87,6 +87,7 @@
     "@nestjs/websockets": "4.6.6",
     "@nguniversal/express-engine": "5.0.0-beta.6",
     "@nguniversal/module-map-ngfactory-loader": "5.0.0-beta.6",
+    "@types/request": "2.47.0",
     "body-parser": "1.18.2",
     "bootstrap": "3.3.7",
     "cookie-parser": "1.4.3",
@@ -98,10 +99,12 @@
     "jsonwebtoken": "8.1.1",
     "mongoose": "4.13.9",
     "passport": "0.4.0",
+    "passport-facebook-token": "^3.3.0",
     "passport-jwt": "3.0.1",
     "passport-local": "1.0.0",
     "redis": "2.8.0",
     "reflect-metadata": "0.1.10",
+    "request": "2.85.0",
     "rxjs": "5.5.6",
     "zone.js": "0.8.20"
   }

src/client/app/components/recipes/recipes.component.html

@@ -16,6 +16,7 @@
     <button mat-button (click)="signUp()">Sign Up</button>
     <button mat-button (click)="signIn()">Sign In</button>
     <button mat-button (click)="getProtected()">Get Protected</button>
+    <button mat-button (click)="facebookLogin()">Facebook Login</button>
   </div>
   <div class="col-md-6">
     <router-outlet></router-outlet>

src/client/app/components/recipes/recipes.component.ts

@@ -3,6 +3,7 @@ import { RecipeItem } from './recipes-list/recipe-item/recipe-item.component';
 import { RecipesService } from '../../services/recipes.service';
 import { AuthService } from '../../services/auth.service';
 import { FormControl, Validators } from '@angular/forms';
+import { ActivatedRoute, Params, Router } from '@angular/router';
 
 @Component({
   selector: 'app-recipes',
@@ -26,10 +27,24 @@ export class RecipesComponent implements OnInit {
 
   constructor(
     private readonly recipesService: RecipesService,
-    private readonly authService: AuthService
+    private readonly authService: AuthService,
+    private readonly route: ActivatedRoute,
+    private readonly router: Router
   ) { }
 
   ngOnInit() {
+    this.route.queryParams.subscribe((params: Params) => {
+      if (Object.keys(params).length) {
+        this.authService.requestFacebookAccessToken(params.code)
+          .subscribe((params: Params) => {
+            this.authService.facebookSignIn(params.access_token)
+              .subscribe((params: Params) => {
+                this.router.navigate(['/']);
+              });
+          });
+      }
+    });
+
     this.recipesService.getRecipes()
       .then((recipes: RecipeItem[]) => this.recipes = recipes);
   }
@@ -59,4 +74,11 @@ export class RecipesComponent implements OnInit {
         console.log(res);
       });
   }
+
+  facebookLogin() {
+    this.authService.requestFacebookRedirectUri()
+      .subscribe((response: {redirect_uri: string}) => {
+        window.location.replace(response.redirect_uri);
+      });
+  }
 }

src/client/app/services/auth.service.ts

@@ -27,6 +27,18 @@ export class AuthService {
     });
   }
 
+  requestFacebookRedirectUri(): Observable<any> {
+    return this.httpClient.get('api/auth/facebook/uri');
+  }
+
+  requestFacebookAccessToken(code: string): Observable<any> {
+    return this.httpClient.post('api/auth/facebook/token', { code });
+  }
+
+  facebookSignIn(access_token: string) {
+    return this.httpClient.post('api/auth/facebook/signin', { access_token });
+  }
+
   getProtected(): Observable<any> {
     return this.httpClient.get(`api/auth/authorized`);
   }

src/server/modules/auth/auth.controller.ts

@@ -17,6 +17,21 @@ export class AuthController {
     return await this.authService.createToken(req.user);
   }
 
+  @Get('facebook/uri')
+  async requestFacebookRedirectUrl(): Promise<{redirect_uri: string}> {
+    return await this.authService.requestFacebookRedirectUri();
+  }
+
+  @Post('facebook/token')
+  async requestFacebookAccessToken(@Req() req: Request): Promise<IToken> {
+    return await this.authService.requestFacebookAccessToken(req.body.code);
+  }
+
+  @Post('facebook/signin')
+  async facebookSignIn(@Req() req: Request): Promise<any> {
+    return await this.authService.createToken(req.user);
+  }
+
   @Get('authorized')
   public async authorized() {
     console.log('Authorized route...');

src/server/modules/auth/auth.module.ts

@@ -7,18 +7,23 @@ import {
 import { authenticate } from 'passport';
 
 import { UserModule } from '../user/user.module';
+import { authProviders } from './auth.providers';
 import { AuthService } from './auth.service';
 import { LocalStrategy } from './passport/local.strategy';
 import { JwtStrategy } from './passport/jwt.strategy';
+import { FacebookStrategy } from './passport/facebook.strategy';
 import { AuthController } from './auth.controller';
 import { bodyValidatorMiddleware } from './middlewares/body-validator.middleware';
 
+
 @Module({
   imports: [UserModule],
   components: [
+    ...authProviders,
     AuthService,
     LocalStrategy,
-    JwtStrategy
+    JwtStrategy,
+    FacebookStrategy
   ],
   controllers: [AuthController],
   exports: [AuthService]
@@ -39,6 +44,10 @@ export class AuthModule implements NestModule {
       ])
       .forRoutes({ path: 'api/auth/signin', method: RequestMethod.POST });
 
+    consumer
+      .apply(authenticate('facebook', { session: false }))
+      .forRoutes({ path: 'api/auth/facebook/signin', method: RequestMethod.POST });
+
     consumer
       .apply(authenticate('jwt', { session: false }))
       .forRoutes({ path: 'api/auth/authorized', method: RequestMethod.ALL });

src/server/modules/auth/auth.providers.ts

@@ -0,0 +1,9 @@
+import { FACEBOOK_CONFIG_TOKEN } from '../../server.constants';
+import { facebookConfig } from './config/facebook-config';
+
+export const authProviders = [
+  {
+    provide: FACEBOOK_CONFIG_TOKEN,
+    useValue: facebookConfig
+  }
+];

src/server/modules/auth/auth.service.ts

@@ -1,15 +1,18 @@
 import { Component, Inject } from '@nestjs/common';
 import { Model } from 'mongoose';
 import { sign } from 'jsonwebtoken';
+import { get, Response } from 'request';
 
-import { SERVER_CONFIG, USER_MODEL_TOKEN } from '../../server.constants';
+import { SERVER_CONFIG, USER_MODEL_TOKEN, FACEBOOK_CONFIG_TOKEN } from '../../server.constants';
 import { IUser } from '../user/interfaces/user.interface';
 import { IToken } from './interfaces/token.interface';
+import { IFacebookConfig } from './interfaces/facebook-config.interface';
 
 @Component()
 export class AuthService {
   constructor(
-    @Inject(USER_MODEL_TOKEN) private readonly userModel: Model<IUser>
+    @Inject(USER_MODEL_TOKEN) private readonly userModel: Model<IUser>,
+    @Inject(FACEBOOK_CONFIG_TOKEN) private readonly fbConfig: IFacebookConfig
   ) {}
 
   async createToken(user: IUser): Promise<IToken> {
@@ -32,4 +35,41 @@ export class AuthService {
 
     return false;
   }
+
+  async requestFacebookRedirectUri(): Promise<{redirect_uri: string}> {
+    const queryParams: string[] = [
+      `client_id=${this.fbConfig.client_id}`,
+      `redirect_uri=${this.fbConfig.oauth_redirect_uri}`,
+      `state=${this.fbConfig.state}`
+    ];
+    const redirect_uri: string = `${this.fbConfig.login_dialog_uri}?${queryParams.join('&')}`;
+
+    return {
+      redirect_uri
+    };
+  }
+
+  async requestFacebookAccessToken(code: string): Promise<any> {
+    const queryParams: string[] = [
+      `client_id=${this.fbConfig.client_id}`,
+      `redirect_uri=${this.fbConfig.oauth_redirect_uri}`,
+      `client_secret=${this.fbConfig.client_secret}`,
+      `code=${code}`
+    ];
+    const uri: string = `${this.fbConfig.access_token_uri}?${queryParams.join('&')}`;
+
+    return new Promise((resolve: Function, reject: Function) => {
+      get(uri, (error: Error, response: Response, body: any) => {
+        if (error) {
+          return reject(error);
+        }
+
+        if (body.error) {
+          return reject(body.error);
+        }
+
+        resolve(body);
+      });
+    });
+  }
 }

src/server/modules/auth/config/facebook-config.ts

@@ -0,0 +1,10 @@
+import { IFacebookConfig } from '../interfaces/facebook-config.interface';
+
+export const facebookConfig: IFacebookConfig = {
+  login_dialog_uri: 'https://www.facebook.com/v2.12/dialog/oauth',
+  access_token_uri: 'https://graph.facebook.com/v2.12/oauth/access_token',
+  client_id: '545785722443649',
+  client_secret: 'a7b3b484ed5b0217b89824541eca1f4e',
+  oauth_redirect_uri: 'http://localhost:4200/recipes',
+  state: '{fbstate}'
+};

src/server/modules/auth/interfaces/facebook-config.interface.ts

@@ -0,0 +1,8 @@
+export interface IFacebookConfig {
+  login_dialog_uri: string;
+  access_token_uri: string;
+  client_id: string;
+  client_secret: string;
+  oauth_redirect_uri: string;
+  state: string;
+}

src/server/modules/auth/passport/facebook.strategy.ts

@@ -0,0 +1,25 @@
+import { Component, Inject } from '@nestjs/common';
+import { use } from 'passport';
+
+import { FACEBOOK_CONFIG_TOKEN } from '../../../server.constants';
+import { IFacebookConfig } from '../interfaces/facebook-config.interface';
+
+const FacebookTokenStrategy = require('passport-facebook-token');
+
+@Component()
+export class FacebookStrategy {
+  constructor(
+    @Inject(FACEBOOK_CONFIG_TOKEN) private readonly fbConfig: IFacebookConfig
+  ) {
+    this.init();
+  }
+
+  private init(): void {
+    use('facebook', new FacebookTokenStrategy({
+      clientID: this.fbConfig.client_id,
+      clientSecret: this.fbConfig.client_secret
+    }, function(accessToken: string, refreshToken: string, profile: any, done: Function) {
+      console.log(profile);
+    }))
+  }
+}

src/server/server.constants.ts

@@ -6,6 +6,7 @@ export const SERVER_CONFIG: IEnvironmentConfig = Config[env];
 
 export const DB_CONNECTION_TOKEN: string = 'DbConnectionToken';
 export const USER_MODEL_TOKEN: string = 'UserModelToken';
+export const FACEBOOK_CONFIG_TOKEN: string = 'FacebookConfigToken';
 
 export const MESSAGES = {
   UNAUTHORIZED_EMAIL_IN_USE: 'The email already exists',