Antes de logar no sistema - Angular

Fala guilherme, tudo bom?

Angular js - Essa parte de interceptors pode ti ajudar: https://www.youtube.com/watch?v=XrX59s_v3U0

Angular 2+ - Você irá usar esse método: this.router.navigate(['LoggedoutPage']); - Esse post tem uma forma de implementar: https://medium.com/@ryanchenkie_40935/angular-authentication-using-route-guards-bf7a4ca13ae3

Até o momento está assim:

Então, tenho este serviço de Anti Guard.

 import { Injectable } from '@angular/core';
 import { Router, CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router';
 import { AuthenticationService } from '../servico/authentication/authentication.service';

 @Injectable()
 export class CanActivateAuthGuard implements CanActivate {

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

   canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot) {
     if (this.authService.isLoggedIn()) {
         return true;
     }
     this.router.navigate(['/authentication']);
     return false;
   }
 }

Rota

 import { Routes } from '@angular/router';

 import { FullComponent } from './layouts/full/full.component';
 import { AppBlankComponent } from './layouts/blank/blank.component';

 export const AppRoutes: Routes = 
 [
   {
     path: '',
     component: FullComponent,
     children: 
     [
       {
         path: '',
         loadChildren: './dashboards/dashboards.module#DashboardsModule'  
         /*pathMatch: 'full',
         redirectTo: '/dashboards/dashboard1', */
       },
       {
         path: 'configuracao',
         loadChildren: './paginas/configuracao/configuracao.module#ConfiguracaoModule'  
       },
       {
         path: 'arquivo',
         loadChildren: './paginas/arquivo/arquivo.module#ArquivoModule'  
       },
       {
         path: 'declaracao',
         loadChildren: './paginas/declaracao/declaracao.module#DeclaracaoModule'  
       },
       {
         path: 'parametro',
         loadChildren: './paginas/parametro/parametro.module#ParametroModule'  
       },
       {
         path: 'endereco',
         loadChildren: './paginas/endereco/endereco.module#EnderecoModule'  
       },
       {
         path: 'contribuinte',
         loadChildren: './paginas/banco/banco.module#BancoModule'  
       },
       {
         path: 'dashboard',
         loadChildren: './dashboards/dashboards.module#DashboardsModule'  
       }
     ]
   },
   {
     path: '',
     component: AppBlankComponent,
     children: 
     [
       {
         path: 'authentication',
         loadChildren: './authentication/authentication.module#AuthenticationModule'
       }
     ]
   },
   {
     path: '**',
     redirectTo: '404' 
   }
 ];

Não consegui implementar.

Serviço de autenticação

import { Injectable } from '@angular/core';
import { Http, Headers, Response } from '@angular/http';
import { Observable } from 'rxjs/Rx';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';
import 'rxjs/add/observable/throw';

import { Usuario } from '../../modelo/usuario/usuario.model';
import { BASE_AUT_URL } from '../base-api-url-defaul';

@Injectable()
export class AuthenticationService {

    private base: string;
    private options: Function;

    private headers = new Headers({
        'Content-Type': 'application/json',
        'Accept': 'application/json',
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Credentials': 'true'
    });

    constructor(private http: Http) {
        this.base = BASE_AUT_URL
     }

     login(usuario: Usuario): Observable<boolean> {
         console.log(this.headers);
         return this.http.post(this.base, JSON.stringify({login: usuario.login, senha: usuario.senha}), {headers: this.headers})
             .map((response: Response) => {
                 let token = response.json() && response.json().token;
                 if (token) {
                     localStorage.setItem('currentUser', 
                     JSON.stringify({ username: usuario.login, token: token }));
                     localStorage.setItem('token', token);
                     localStorage.setItem('user', JSON.stringify(usuario.login));
                     localStorage.setItem('usuario', response.json().usuario);
                     localStorage.setItem('nomeUsuario', response.json().nomeUsuario);
                     localStorage.setItem('grupoUsuario', response.json().grupo);
                     return true;
                 } else {
                     return false;
                 }
             }
         ).catch(
             (error:any) => Observable.throw(error.json().error || 'Server error')
         );
     }

     getToken(): String {
         var currentUser = JSON.parse(localStorage.getItem('currentUser'));
         var token = currentUser && currentUser.token;
         return token ? token : "";
     }

     logout(): void {
         localStorage.removeItem('currentUser');
     }

     isLoggedIn(): boolean {
         var token: String = this.getToken();
         return token && token.length > 0;
     }
 }

Fiz assim e assim resolveu.

CanActivateAuthGuard

  import { Injectable } from '@angular/core';
    import { Router, CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router';
    import { AuthenticationService } from '../servico/authentication/authentication.service';

    @Injectable()
    export class CanActivateAuthGuard implements CanActivate {

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

      canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot) {
        if (this.authService.isLoggedIn()) {
          return true;
        }
        this.router.navigate(['/authentication/login']);
        return false;
      }
    }

Rotas seguras

    import { Routes } from '@angular/router';
    import { ArquivoComponent } from './arquivo/arquivo.component';
    import { ArquivoFormComponent } from './arquivo-form/arquivo-form.component';
    import { CanActivateAuthGuard } from '../../authentication/can-activate.authguard';

    export const ArquivoRoutes: Routes = [
      {
        path: '',
        children: [
          {
            path: '',
            component: ArquivoComponent,
            canActivate: [CanActivateAuthGuard] 
          }
          , {
            path: 'novo',
            component: ArquivoFormComponent,
            canActivate: [CanActivateAuthGuard] 
          }
        ]
      }
    ];

AuthenticationService

    import { Injectable } from '@angular/core';
    import { Http, Headers, Response } from '@angular/http';
    import { Observable } from 'rxjs/Rx';
    import 'rxjs/add/operator/map';
    import 'rxjs/add/operator/catch';
    import 'rxjs/add/observable/throw';

    import { Usuario } from '../../modelo/usuario/usuario.model';
    import { BASE_AUT_URL } from '../base-api-url-defaul';

    @Injectable()
    export class AuthenticationService {

        private base: string;
        private options: Function;

        private headers = new Headers({
            'Content-Type': 'application/json',
            'Accept': 'application/json',
            'Access-Control-Allow-Origin': '*',
            'Access-Control-Allow-Credentials': 'true'
        });

        constructor(private http: Http) {
            this.base = BASE_AUT_URL
        }

        login(usuario: Usuario): Observable<boolean> {
            console.log(this.headers);
            return this.http.post(this.base, JSON.stringify({login: usuario.login, senha: usuario.senha}), {headers: this.headers})
                .map((response: Response) => {
                    let token = response.json() && response.json().token;
                    if (token) {
                        localStorage.setItem('currentUser', JSON.stringify({ username: usuario.login, token: token }));
                        localStorage.setItem('token', token);
                        localStorage.setItem('user', JSON.stringify(usuario.login));
                        localStorage.setItem('usuario', response.json().usuario);
                        localStorage.setItem('nomeUsuario', response.json().nomeUsuario);
                        localStorage.setItem('grupoUsuario', response.json().grupo);
                        return true;
                    } else {
                        return false;
                    }
                }
            ).catch(
                (error:any) => Observable.throw(error.json().error || 'Server error')
            );
        }

        getToken(): String {
            //var currentUser = JSON.parse(localStorage.getItem('currentUser'));
            //var token = currentUser && currentUser.token;
            var token = localStorage.getItem('token');
            return token ? token : "";
        }

        logout(): void {
            localStorage.removeItem('currentUser');
            localStorage.removeItem('token');
            localStorage.removeItem('user');
            localStorage.removeItem('usuario');
            localStorage.removeItem('nomeUsuario');
            localStorage.removeItem('grupoUsuario');
        }

        isLoggedIn(): boolean {
            var token: String = this.getToken();
            return token && token.length > 0;
        }
    }

usei como referência esse artigo: Angular Authentication: Using Route Guards