Angular2 - Redirect to calling url after successful login

Question

I have my application up and running with Angular 2.1.0. The routes are protected via router Guards, canActivate.

When pointing the browser to a protected area like "localhost:8080/customers" I get redirected to my login page just like expected.

But after a successful login, I would like to be redirected back to calling URL ("/customers" in this case).

The code for handling the login looks like this

login(event, username, password) {
  event.preventDefault();
  var success = this.loginService.login(username, password);
  if (success) {
    console.log(this.router);
    this.router.navigate(['']);
  } else {
    console.log("Login failed, display error to user");
  }
}

The problem is, I don't know how to get a hold of the calling url from inside the login method.

I did find a question (and answer) regarding this but couldn't really make any sense of it. Angular2 Redirect After Login

Answer 1

There's a great example in the Angular Docs, Teach Authguard To Authenticate. Basically the idea is using your AuthGuard to check for your login status and store the url on your AuthService. Some of the code is on the url above.

AuthGuard

import { Injectable }       from '@angular/core';
import {
  CanActivate, Router,
  ActivatedRouteSnapshot,
  RouterStateSnapshot
}                           from '@angular/router';
import { AuthService }      from './auth.service';

@Injectable()
export class AuthGuard implements CanActivate {
  constructor(private authService: AuthService, private router: Router) {}

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean {
    let url: string = state.url;

    return this.checkLogin(url);
  }

  checkLogin(url: string): boolean {
    if (this.authService.isLoggedIn) { return true; }

    // Store the attempted URL for redirecting
    this.authService.redirectUrl = url;

    // Navigate to the login page with extras
    this.router.navigate(['/login']);
    return false;
  }
}

AuthService or your LoginService

import { Injectable } from '@angular/core';
import { Http, Response } from '@angular/http';
import { Router } from '@angular/router';

@Injectable()
export class AuthService {
  isLoggedIn: boolean = false;    
  // store the URL so we can redirect after logging in
  public redirectUrl: string;

  constructor (
   private http: Http,
   private router: Router
  ) {}

  login(username, password): Observable<boolean> {
    const body = {
      username,
      password
    };
    return this.http.post('api/login', JSON.stringify(body)).map((res: Response) => {
      // do whatever with your response
      this.isLoggedIn = true;
      if (this.redirectUrl) {
        this.router.navigate([this.redirectUrl]);
        this.redirectUrl = null;
      }
    }
  }

  logout(): void {
    this.isLoggedIn = false;
  }
}

I think this will give an idea how things work, of course you probably need to adapt to your code

Answer 2

This code will handle your request:

export class AuthGuard implements CanActivate {
  constructor(private authService: AuthService,
              private router: Router) {
  }

  canActivate(next: ActivatedRouteSnapshot,
              state: RouterStateSnapshot): Observable<boolean> {
    return this.authService.isVerified
      .take(1)
      .map((isVerified: boolean) => {
        if (!isVerified) {
          this.router.navigate(['/login'], {queryParams: {returnUrl: state.url}});
          return false;
          // return true;
        }
        return true;
      });
  }
}

but be aware that the URL params will not pass with the URL!!

You can find a nice tutorial here : http://jasonwatmore.com/post/2016/12/08/angular-2-redirect-to-previous-url-after-login-with-auth-guard