使用CanActivate的AngularFire2(4.0)身份验证无效

Question

我正在构建一个基于以下教程的Angular 4 + FireBase(4.0.0.rc0)应用程序:https://coursetro.com/posts/code/32/Create-a-Full-Angular-Authentication-System-with -Firebase

本教程基于较旧版本的FireBase.我几乎可以将所有内容转换为最新版本.我正在努力改变这个canActivate功能.它会引发Observable.from(this.afAuth)以下错误:

[ts]
Argument of type 'AngularFireAuth' is not assignable to parameter of type 'ArrayLike<{}>'.
Property 'length' is missing in type 'AngularFireAuth'.
(property) AuthGuard.afAuth: AngularFireAuth

export class AuthGuard implements CanActivate {

  constructor(private afAuth: AngularFireAuth, private router: Router) { }

  canActivate(): Observable<boolean> {
    return Observable.from(this.afAuth)
      .take(1)
      .map(state => !!state)
      .do(authenticated => {
        if
         (!authenticated) this.router.navigate(['/login']);
      })
  }
}

我怎样才能做到这一点？

谢谢!

Answer 1

它应该是afAuth.authState,它已经Observable<firebase.User>是你不需要的Observable.from

constructor(private afAuth: AngularFireAuth, private router: Router) { }

canActivate(): Observable<boolean> {
  return this.afAuth.authState
    .take(1)
    .map(authState => !!authState)
    .do(authenticated => {
      if (!authenticated) {
        this.router.navigate(['/login']);
      }
    });
}