CanActivate interface

Interface that a class can implement to be a guard deciding if a route can be activated.

interface CanActivate {
  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean
}

Example

class UserToken {}
class Permissions {
  canActivate(user: UserToken, id: string): boolean {
    return true;
  }
}

@Injectable()
class CanActivateTeam implements CanActivate {
  constructor(private permissions: Permissions, private currentUser: UserToken) {}

  canActivate(
    route: ActivatedRouteSnapshot,
    state: RouterStateSnapshot
  ): Observable<boolean>|Promise<boolean>|boolean {
    return this.permissions.canActivate(this.currentUser, route.params.id);
  }
}

@NgModule({
  imports: [
    RouterModule.forRoot([
      {
        path: 'team/:id',
        component: TeamCmp,
        canActivate: [CanActivateTeam]
      }
    ])
  ],
  providers: [CanActivateTeam, UserToken, Permissions]
})
class AppModule {}

You can alternatively provide a function with the canActivate signature:

@NgModule({
  imports: [
    RouterModule.forRoot([
      {
        path: 'team/:id',
        component: TeamCmp,
        canActivate: ['canActivateTeam']
      }
    ])
  ],
  providers: [
    {
      provide: 'canActivateTeam',
      useValue: (route: ActivatedRouteSnapshot, state: RouterStateSnapshot) => true
    }
  ]
})
class AppModule {}