Angular2 routing canActivate and AuthGuard (JWT) with user role parameter

Question

In this exaple project with JWT authentication we se how to allow only authenticated users to some route:

import { RouterConfig } from '@angular/router'; import { Home } from './home'; import { Login } from './login'; import { Signup } from './signup'; import { AuthGuard } from './common/auth.guard';  export const routes: RouterConfig = [   { path: '',       component:  Login },   { path: 'login',  component: Login },   { path: 'signup', component: Signup },   { path: 'home',   component: Home, canActivate: [AuthGuard] },   { path: '**',     component: Login }, ]; 

I would like make step further and also indicate what user role have 'access' to route - but I don't know how to pass argument to canActivate AuthGuard (src). So I would like to achieve something like this (for instance I have two roles: Admin and Employee):

  { path: 'home',   component: Home, canActivate: [AuthGuard] },   { path: 'users',   component: AdminUsers, canActivate: [AuthGuard('Admin')] },   { path: 'users',   component: Employees, canActivate: [AuthGuard('Employee')] }, 

Where my AuthGuard could look something like this (where userRole(= Admin or Employee or null) is passed parameter to AuthGuard):

@Injectable() export class AuthGuard implements CanActivate {   constructor(private router: Router) {}    canActivate(userRole) {     if (!userRole || JWT.user().role == userRole) {       return true;     }      this.router.navigate(['/login']);     return false;   } } 

where JWT.user.role is helper which read user role stored in JWT token. Is there a way to do something similar like above idea?

Answer 1

You can set the data parameter of the route with the role like this

const appRoutes: Routes = [  {     path: 'account/super-secure',     component: SuperSecureComponent,     canActivate: [RoleGuard],     data: { roles: ['super-admin', 'admin'] }   }];

and then have this in canActivate of RoleGuard:

canActivate(route: ActivatedRouteSnapshot,      state: RouterStateSnapshot): boolean {        let roles = route.data["roles"] as Array<string>;      return (roles == null || roles.indexOf("the-logged-user-role") != -1);  }

I think this could be another way of doing it instead of creating guard for every role. I would actually take this rout since it requires less code and handles the problem very nicely.

Answer 2

The signature for CanActivate won't allow you to pass a userRole like you want to. https://github.com/angular/angular/blob/2.0.0-rc.4/modules/%40angular/router/src/interfaces.ts#L54

It's probably best to do separate classes for each of your user role cases. That's the guidance in the official docs too: https://angular.io/docs/ts/latest/api/router/index/CanActivate-interface.html