CustomHttp内访问EventEmitter服务 [英] Access EventEmitter Service inside of CustomHttp

问题描述

对于所有的HTTP请求

我已经创建自定义拦截器：

 进口{} EventEmitterService从./EventEmitter.service@Injectable（）
出口类CustomHttp扩展HTTP {
    构造函数（后端：ConnectionBackend，defaultOptions：RequestOptions，_eventEmitterService：EventEmitterService）{
        超（后端，defaultOptions）;
    }
 得到（网址：字符串，期权？：RequestOptionsArgs）：可观察＆LT;应变及GT; {
        返回super.get（URL，{标题：interceptorHeaders}）赶上（（RES）=＆GT; {。
            如果（res.status === 403）{
                的console.log（拦截器在这里）
                this._eventEmitterService.logout.emit（403）;
            }
            返回Observable.of（RES）;
        }）;
    }
}
 

伟大的工程 - 每当我收到从我得到的服务器403响应：

 拦截器在这里
 

在我的控制台。

然而，与注射 EventEmitterService 进入捕捉功能的问题。每当我在它的内部，我不能访问 CustomHttp - 我只能访问某些观测，即使当我调试我的构造函数 - 我可以看到 EventEmitterService 已注入

这是我如何注入 EventEmitterService ：

 引导程序（App [...，
EventEmitterService，
    新的供应商（HTTP，{
        useFactory：（后端：XHRBackend，defaultOptions：RequestOptions，_eventEmitterService：EventEmitterService）= GT;新CustomHttp（后端，defaultOptions，_eventEmitterService）
        DEPS：[XHRBackend，RequestOptions，EventEmitterService]
    }），...]）;
 

解决方案

也许你只是错过了私人关键字在 _eventEmitterService <水平/ code>的 CustomHttp 构造函数参数：

 出口类CustomHttp扩展HTTP {
构造函数（后端：ConnectionBackend，
            defaultOptions：RequestOptions，
            私人_eventEmitterService：EventEmitterService）{//＆下; ----
  超（后端，defaultOptions）;
}
 

I have created custom interceptor for all Http requests:

import {EventEmitterService} from "./EventEmitter.service";

@Injectable()
export class CustomHttp extends Http {
    constructor(backend: ConnectionBackend, defaultOptions: RequestOptions, _eventEmitterService:EventEmitterService) {
        super(backend, defaultOptions);
    }
 get(url: string, options?: RequestOptionsArgs): Observable<Response> {
        return super.get(url,{headers: interceptorHeaders}).catch((res)=>{
            if (res.status === 403){
                console.log("Interceptor here")
                this._eventEmitterService.logout.emit("403");
            }
            return Observable.of(res);
        });
    }
}

Which works great - whenever I am receiving a 403 response from the server I get :

Interceptor here

in my console.

However, there is an issue with injecting EventEmitterService into the catch function. Whenever I am inside of it, I cant access CustomHttp - I only have access to some Observable, even though when I debug my constructor - I can see the EventEmitterService has been injected.

This is how I inject EventEmitterService:

bootstrap(App,[...,
EventEmitterService,
    new Provider(Http, {
        useFactory: (backend: XHRBackend, defaultOptions: RequestOptions, _eventEmitterService:EventEmitterService) => new CustomHttp(backend, defaultOptions,_eventEmitterService),
        deps: [XHRBackend, RequestOptions,EventEmitterService]
    }),...]);

解决方案

Perhaps you just missed the private keyword at the level of the _eventEmitterService parameter of the CustomHttp constructor:

export class CustomHttp extends Http {
constructor(backend: ConnectionBackend,
            defaultOptions: RequestOptions,
            private _eventEmitterService:EventEmitterService) { // <----
  super(backend, defaultOptions);
}

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