simple role management

src/app/services/user/role.directive.ts

@@ -0,0 +1,55 @@
+import {Directive, ElementRef, Input, OnInit, TemplateRef, ViewContainerRef} from '@angular/core';
+import {roles} from './roles';
+import {UserService} from './user.service';
+import {User} from './user';
+
+@Directive({
+  selector: '[appRole]'
+})
+export class RoleDirective implements OnInit {
+  @Input() appRole: roles[] = [];
+  private currentUser: User;
+  private loggedIn: boolean;
+
+  constructor(
+    private element: ElementRef,
+    private templateRef: TemplateRef<any>,
+    private viewContainer: ViewContainerRef,
+    private userService: UserService
+  ) {
+
+  }
+
+  public ngOnInit(): void {
+    this.userService.user$.subscribe(user => {
+      this.currentUser = user;
+      this.updateView();
+    });
+    this.userService.loggedIn$().subscribe(_ => {
+      this.loggedIn = !!_;
+      this.updateView();
+    });
+    this.updateView();
+  }
+
+  private updateView() {
+    if (this.loggedIn && this.checkPermission()) {
+      this.viewContainer.createEmbeddedView(this.templateRef);
+    } else {
+      this.viewContainer.clear();
+    }
+  }
+
+  private checkPermission() {
+    if (this.currentUser && this.currentUser.role) {
+      if (this.currentUser.role === 'admin') return true;
+      for (const role of this.appRole) {
+        if (this.currentUser.role === role) return true;
+      }
+    }
+
+    return false;
+  }
+
+
+}