source: trip-planner-front/src/app/auth/auth.guard.ts

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

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

  constructor(private router : Router){}
  canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot): boolean{
    
      if(localStorage.getItem('token') != null)
      return true;
      this.router.navigate(['planners']);
      return false;
  }
  
}