在检查用户之前,AuthGuard不会等待身份验证完成

Question

我在这里阅读了指南:https://angular.io/docs/ts/latest/guide/router.html

看起来非常简单,但是,我不确定如何在auth guard(canActivate)中使用angularfire2的身份验证.我试过的是:

AuthService

import { Injectable } from '@angular/core';
import { AngularFire } from 'angularfire2';

@Injectable()
export class AuthService {

  private user: any;

  constructor(private af: AngularFire) {
    this.af.auth.subscribe(user => {
      this.user = user;
    })
  }

  get authenticated(): boolean {
    return this.user ? true : false;
  }

}

AuthGuard

@Injectable()
export class AuthGuard implements CanActivate {

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

  canActivate(): Observable<boolean> | boolean {
    if (this.authService.authenticated)
      return true;

    this.router.navigate(['/login']);
    return false;
  } 

}

我还将AuthService添加到bootstrap提供程序.

这种工作正常,但是,我的主要问题是当我刷新(或最初加载)页面时,AuthGuard它总是将我重定向到登录页面,因为AuthGuard它不等待认证响应.有没有办法等待身份验证完成(即使它失败),然后检查用户是否经过身份验证？

Answer 1

问题出在你的代码上.在AuthGuard中,您检查authenticated()方法的结果,该方法很可能返回false,因为仍未设置用户属性.试试这个:

AuthService:

import { Injectable } from '@angular/core';
import { AngularFire } from 'angularfire2';';
import { Observable } from 'rxjs/Observable';

@Injectable()
export class AuthService {

  private user: any;

  constructor(private af: AngularFire) { }
  setUser(user) { this.user = user; }
  getAuthenticated(): Observable<any> { return this.af.auth; }
}

AuthGuard:

@Injectable()
export class AuthGuard implements CanActivate {

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

  canActivate(): Observable<boolean> | boolean {
    // here check if this is first time call. If not return 
    // simple boolean based on user object from authService
    // otherwise:

    return this.authService.getAuthenticated.map(user => {
          this.authService.setUser(user);
          return user ? true : false;
    })

  } 
}

Answer 2

在某些版本的路由器中可能会有所不同,但我需要返回一个完成的observable .

import { CanActivate, Router } from '@angular/router'

@Injectable()
export class AuthGuard implements CanActivate {
  constructor(private af: AngularFire, private router: Router) { }

  canActivate(): Observable<boolean> {
    return this.af.auth.map(user => {
      if (user != null)
        return true
      this.router.navigate(['/login'])
    })
    .take(1) // To make the observable complete after the first emission
  }
}