angular - Angular 6 中的异步 authguard

Question

我想在以 Angular 授予对特定路由的访问权限之前提供服务器端身份验证。

我有一个实现 CanActivate 的 AuthGuard 和一个服务 AuthService。authService 已经有一个 private loggedIn: BehaviorSubject<boolean> = new BehaviorSubject<boolean>(null);
订阅哪些 View 以了解用户是否登录。我真的不知道我的方法是否错误，但它似乎不起作用。

这是我在 auth.guard.ts 中的内容:

canActivate(next: ActivatedRouteSnapshot, state: RouterStateSnapshot) : Observable<boolean> {
    return this.authService.isAuthenticated().map((isLoggedIn) => {
        if (isLoggedIn) {
            return true;
        } else {
            this.router.navigate(['/login']);
            return false;
        }
    })
}

这是 auth.service.ts:

    @Injectable()
export class AuthService {
    private loggedIn: BehaviorSubject<boolean> = new BehaviorSubject<boolean>(null);

    constructor(
        private router: Router,
        private http: HttpClient
    ) {

    }

    get isLoggedIn() {
        return this.loggedIn.asObservable();
    }

    isAuthenticated() : Observable<boolean> {
        const headers = new HttpHeaders().set("X-Requested-With", "XMLHttpRequest");

        return this.http.get('/user', {headers: headers}).map(
            response => {
                if (response['username']) {
                    this.loggedIn.next(true);
                    return true;
                } else {
                    return false;
                }
            }
        )
    }

Answer 1

这是 RXJS6 的方法，在身份验证服务中添加了一个变量 _isAuthenticated 以在禁用标志时请求服务器状态。我希望这对其他人有帮助。

确保 canActivate 返回一个纯 bool 值或一个可观察值。路由处理程序将订阅给定的可观察对象并对来自值流的第一个 bool 值使用react。

auth.guard.ts

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

import { Observable } from 'rxjs/';
import { map, finalize } from 'rxjs/operators';
import { DataService } from '../data.service';
import { AuthenticationService } from './authentication.service';

@Injectable()
export class AuthenticationGuard implements CanActivate {

  constructor(private router: Router,
              private dataService: DataService,
              private authenticationService: AuthenticationService) { }

  canActivate(): any {
    const isAuthenticated = this.authenticationService.isAuthenticated();

    // All good
    if ( isAuthenticated ) {
      return true;

    // Hmm, let's verify the user first
    } else {
      return this.authenticationService.isSessionAlive()
        .pipe(
          map(res => {

            // No valid session; let's move to the login page
            if ( res === false ) {
              this.router.navigate(['/login'], { replaceUrl: true });
            }

            return res;
          })
        );
    }
  }

}

auth.service.ts(我使用的是 rxjs 6)

import { Injectable } from '@angular/core';
import { Observable } from 'rxjs';
import { DataService } from '@app/core';

@Injectable()
export class AuthenticationService {

  private _isAuthenticated = false;

  constructor(
    private dataService: DataService
  ) {}

  isAuthenticated(): boolean {
    return this._isAuthenticated;
  }

  isSessionAlive(): Observable<any> {
    return Observable.create((observer) => {
      this.dataService.SessionIsAlive()
        .subscribe((res) => {
          this._isAuthenticated = true;
          observer.next(res.success); // your server response
        }, (err) => {
          this._isAuthenticated = false;
          observer.next(false);
          // observer.error(err); // won't work here you need to use next
        });
    });
  }
}