auth-guard.service.ts

import {Injectable} from '@angular/core';
import {AuthService} from "./auth.service";
import {Router} from "@angular/router";
import {AlertService} from "./alert.service";

@Injectable({
  providedIn: 'root'
})
export class AuthGuardService {

  constructor(public auth: AuthService, public router: Router, private alertService: AlertService) {
  }

  canActivate(): boolean {
    if (!this.auth.isAuthenticated()) {
      this.alertService.error('Log In');
      this.router.navigate(['/']);
      return false;
    }
    return true;
  }
}