HTTP侦听器内的模块导入未定义

Question

我有一个HTTP拦截器来监视401错误和超时错误。当我在其中导入服务时。这是说服务是未定义的

我的HTTP拦截器

// dependencies
import { Injectable } from '@angular/core';
import { ConnectionBackend, XHRBackend, RequestOptions, Request, RequestOptionsArgs, Response, Http, Headers } from '@angular/http';
import { Observable } from 'rxjs/Rx';
import { environment } from '../../../environments/environment';
import { Router } from '@angular/router';

import { NotificationService } from '@sharedServices/notification/notification.service';

@Injectable()
export class HttpInterceptor extends Http {

  constructor(backend: XHRBackend, defaultOptions: RequestOptions, private _router: Router, private _notify: NotificationService) {
    super(backend, defaultOptions);
  }

  request(url: string | Request, options?: RequestOptionsArgs): Observable<Response> {
    return super.request(url, options)
      .timeout(2000) // set timeout 15s for every request
      .catch((error: Response) => {
        if (error.status === 401 || error.status === 403) {
          console.log('unAuthorized access');
          this._router.navigate(['/login'], { queryParams: { returnUrl: this._router.url } });
        }

        if (error['name'] === 'TimeoutError') {
          console.log(this._notify) // undefined here
        }
        return Observable.throw(error);
      });
  }

  get(url: string, options?: RequestOptionsArgs): Observable<Response> {
    url = this.updateUrl(url);
    return super.get(url, this.getRequestOptionArgs(options));
  }

  post(url: string, body: string, options?: RequestOptionsArgs): Observable<Response> {
    url = this.updateUrl(url);
    return super.post(url, body, this.getRequestOptionArgs(options));
  }

  put(url: string, body: string, options?: RequestOptionsArgs): Observable<Response> {
    url = this.updateUrl(url);
    return super.put(url, body, this.getRequestOptionArgs(options));
  }

  delete(url: string, options?: RequestOptionsArgs): Observable<Response> {
    url = this.updateUrl(url);
    return super.delete(url, this.getRequestOptionArgs(options));
  }

  private updateUrl(req: string) {
    return environment.origin + req;
  }

  private getRequestOptionArgs(options?: RequestOptionsArgs): RequestOptionsArgs {

    const request_headers = {
      'Content-Type': 'application/json',
      'X-Requested-By': 'api-client'
    };

    if (options == null) {
      options = new RequestOptions();
    }
    if (options.headers == null) {
      options.headers = new Headers(request_headers);
    }

    return options;
  }
}

我的HTTP拦截器工厂

// dependencies
import { XHRBackend, Http, RequestOptions } from '@angular/http';
import { HttpInterceptor } from './http-interceptor';
import { Router } from '@angular/router';

// shared services
import { NotificationService } from '@sharedServices/notification/notification.service';

export function HttpFactory(xhrBackend: XHRBackend, requestOptions: RequestOptions, _router: Router, _notify: NotificationService): Http {
  return new HttpInterceptor(xhrBackend, requestOptions, _router, _notify);
}

捕获块内的通知未定义。我不明白为什么会发生这种情况。

我对这件事很陌生。我做错了什么？

Answer 1

你做过：-

'deps'：[NotificationService]

在模块中，例如：-

{
 'provide' : Http,
 'useFactory' : HttpFactory,
 'deps' : [NotificationService]

}