javascript - Angular 2 - 无法实例化循环依赖

Question

我创建自定义 XHRBackend 类来全局捕获 401 错误。在 AuthService 中，我有两种使用 http 的方法 - 登录和 refreshToken。所以我有这样的依赖链:Http -> customXHRBackend -> AuthService -> Http。我该如何解决这个问题？

export class CustomXHRBackend extends XHRBackend {
  constructor(browserXHR: BrowserXhr,
              baseResponseOptions: ResponseOptions,
              xsrfStrategy: XSRFStrategy,
              private router: Router,
              private authService: AuthService) {
    super(browserXHR, baseResponseOptions, xsrfStrategy);
  }

  createConnection(request: Request): XHRConnection {
    let connection: XHRConnection = super.createConnection(request);
    connection.response = connection.response
      .catch(this.handleError.bind(this));

    return connection;
  }

  handleError(error: Response | any) {
    console.log('ERROR',error['status']);
    if(error['status'] === 401) {
      this.authService.logout();
      this.router.navigate(['/']);
    }

    return Observable.throw(error);
  }
}

AuthService.ts

@Injectable()
export class AuthService {
  private loggedIn: boolean = false;

  constructor(private http: Http) {
    this.loggedIn = !!localStorage.getItem('authToken');
  }

  login(email: string, password: string): Observable<Response> {
    let headers: Headers = new Headers();
    headers.set('Content-Type', 'application/json');

    return this.http.post('https://httpbin.org/post',
      {
        email: email,
        password: password
      },
      {
        headers: headers
      })
      .map((response) => {
        let res = response.json();

        // if (res['success']) {
        if (res) {
          localStorage.setItem('authToken', res['token']);
          localStorage.setItem('refreshToken', res['refreshToken']);
          console.log('logged');
          this.loggedIn = true;
        }

        return response;
      }
    );
  }

  logout(): void {
    localStorage.removeItem('authToken');
    this.loggedIn = false;

    console.log('Logged out');
  }

  isLogged(): boolean {
    return this.loggedIn;
  }

  refreshToken(): Observable<Response> {
    let headers: Headers = new Headers();
    headers.set('token', localStorage.getItem('token'));
    headers.set('refreshToken', localStorage.getItem('refreshToken'));

    return this.http.get('https://httpbin.org/get', {
      headers: headers
    });
  }

}

在 app.module.ts 中包含 CustomXHRBackend

{
      provide: XHRBackend,
      useFactory: (browserXHR: BrowserXhr,
                   baseResponseOptions: ResponseOptions,
                   xsrfStrategy: XSRFStrategy,
                   router: Router,
                   authService: AuthService) => {
        return new CustomXHRBackend(browserXHR, baseResponseOptions, xsrfStrategy, router, authService);
      },
      deps: [BrowserXhr, ResponseOptions, XSRFStrategy, Router, AuthService]
    }

Answer 1

HTTP 拦截器怎么样...有一篇博客文章 here .
如果你谷歌你会发现更多... Here's你如何将一个连接到你的应用程序模块您可以在拦截器中克隆请求并将 X-CustomAuthHeader 添加到 header 等中