auth-guard.service.ts

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

@Injectable({providedIn: 'root'})
export class AuthGuard implements CanActivate, CanActivateChild {

  constructor(private authService: AuthService, private router: Router) {
  }


  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean | Observable<boolean> | Promise<boolean> {
    return this.authService.isAuthenticated().then((authenticate: boolean) => {
      if (authenticate) {
        return true;
      } else {
        this.router.navigate(['/']);
        return false;
      }
    });
  }

  canActivateChild(childRoute: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean | Observable<boolean> | Promise<boolean> {
    return this.canActivate(childRoute, state);
  }
}