next-ucap-messenger/projects/ucap-webmessenger-app/src/app/guards/auth.guard.ts

import { Injectable } from '@angular/core';
import {
  CanActivate,
  ActivatedRouteSnapshot,
  RouterStateSnapshot,
  UrlTree,
  Router
} from '@angular/router';
import { Store, select } from '@ngrx/store';
import { Observable } from 'rxjs';
import { map, take } from 'rxjs/operators';

import { AppAuthenticationService } from '../services/authentication.service';

@Injectable({
  providedIn: 'root'
})
export class AppAuthGuard implements CanActivate {
  constructor(
    private router: Router,
    private appAuthenticationService: AppAuthenticationService
  ) {}

  canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot
  ):
    | boolean
    | UrlTree
    | Observable<boolean | UrlTree>
    | Promise<boolean | UrlTree> {
    return new Promise<boolean | UrlTree>((resolve, reject) => {
      if (this.appAuthenticationService.authenticated()) {
        resolve(true);
      } else {
        this.router.navigateByUrl('/account/login');
        resolve(false);
      }
    });
  }
}