FoodLoop-Web/src/app/_guards/auth.guard.ts

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

@Injectable()
export class AuthGuard implements CanActivate {

  constructor(private router: Router) { }

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot) {
    if (localStorage.getItem('sessionKey')) {
      console.log('session key found');
      // logged in so return true
      return true;
    }

    // not logged in so redirect to login page with the return url
    console.log('no session key found');
    this.router.navigate(['/login'], { queryParams: { returnUrl: state.url }});
    return false;
  }
}