app.routing.ts

import { NgModule } from '@angular/core';
import { RouterModule, Routes } from '@angular/router';
import { CanActivateRouteGuardService } from './services/can-activate-route-guard.service';
import { CantActivateRouteGuardService } from './services/cant-activate-route-guard.service';


const routes: Routes = [
  {
    path: 'login',
    loadChildren: './components/login-page/login-page.module#LoginPageModule',
    canActivate: [CantActivateRouteGuardService]
  },
  {
    path: 'admin/publishers',
    loadChildren: './components/admin-publishers-page/admin-publishers-page.module#AdminPublishersPageModule',
    canActivate: [CanActivateRouteGuardService]
  }
  
@NgModule({
  imports: [
    RouterModule.forRoot(routes)
  ],
  exports: [RouterModule],
  providers: []
})
export class AppRoutingModule { }

can-activate-route-guard.service.ts

import { Injectable } from '@angular/core';
import { CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot, Router } from '@angular/router';
import { LoginPageMeGQL } from '@src/generated-types';
@Injectable({
  providedIn: 'root'
})

export class CanActivateRouteGuardService implements CanActivate {
  constructor(
    private router: Router,
    private loginPageMeGQL: LoginPageMeGQL
  ) { }

  async canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot
  ) {
    const result = await this.loginPageMeGQL.fetch({}, {
      fetchPolicy: 'cache-first'
    }).toPromise();

    if (!result.data.me) {
      this.router.navigateByUrl('/login');
      return false;
    }
    return true;

  }

}

cant-activate-route-guard.service.ts

import { Injectable } from '@angular/core';
import { CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot, Router } from '@angular/router';
import { LoginPageMeGQL } from '@src/generated-types';
@Injectable({
  providedIn: 'root'
})

export class CantActivateRouteGuardService implements CanActivate {
  constructor(
    private router: Router,
    private loginPageMeGQL: LoginPageMeGQL
  ) { }

  async canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot
  ) {
    const result = await this.loginPageMeGQL.fetch({}, {
      fetchPolicy: 'cache-first'
    }).toPromise();

    if (result.data.me) {
      this.router.navigateByUrl('/');
      return false;
    }
    return true;

  }

}