angular2中的地图问题

Question

I am creating advance login system in angular2. Now i am facing blocker issue. I have created gateway for api communication in angular2. This is my code

gateWay(Method, Url, data) {
    console.log("gateWay  "+Method)
    this.Method = Method
    this.Url = Url
    this.data = data
    if(Method == "get"){
      return this.http.get('http://localhost:3000/' + Url, { headers: this.insertAuthToken }).map((res) => res.json())
                  .map((res) => res.json())
    }else if(Method == "post"){
      return this.http.post('http://localhost:3000/' + Url, JSON.stringify(data), { headers: this.insertAuthToken })
        .map((res) => res.json());
    }else if(Method == "put"){
      return this.http.put('http://localhost:3000/' + Url, JSON.stringify(data), { headers: this.insertAuthToken })
        .map((res) => res.json());
    }else if(Method == "delete"){
      return this.http.delete('http://localhost:3000/' + Url, { headers: this.insertAuthToken })
        .map((res) => res.json());
    }

} If status 200 mean i am able to see status code of response message in console.log. but if i get response as 403 mean i need to process some function in this case i am facing issue i am unable to process those function because i did subscribe error in my component

this.httpService.gateWay('get', 'v1/users/index', undefined)
           .subscribe(
                data => console.log(data),
                error => console.log(error),
                () => console.log("finished")
            )

So please suggest me some idea to trigger function if i get 403 otherwise such as 400 mean need to show message in alert. This is my token setup, here i am resetting token using set Interval

SetTokenDynamically(time) {
    console.log("time " + time)
    clearInterval(this.timer)
    this.timer = setInterval(() => {
      // this.http.get('https://jsonblob.com/api/jsonBlob/56d80451e4b01190df528171')
      this.http.get('http://localhost:3000/v1/users/tokenUpdate', { headers: this.headerRefreshToken })
        .map((res) => res.json())
        .subscribe(
        data => {
          Cookie.setCookie('Token2', data.token + this.a)
          console.log("Call " + this.a)
          this.response = data;
        },
        error => console.log(error),
        () => {

          console.log(this.response)

          this.insertAuthToken = new Headers({
            'AuthToken': this.response.token || ""
          })
          Cookie.setCookie('Authorization', this.response.token)
          this.SetTokenDynamically(this.response.time_expiry_sec)

        }
        );
    }, time);
  }

Answer 1

It's because in the case of a 403 status code, the map callback won't be executed but the catch one (and if not the error callback specified when subscribing).

this.http.get('http://localhost:3000/' + Url, {
   headers: this.insertAuthToken
})
    .map((res) => res.json())
    .catch((res) => { // <------
      if(res.status == 403){
        this.SetTokenDynamically(100);
      }
    });

I guess that you try to dynamically add the token if you receive a 403 error and execute again the request.

Here is a sample:

@Injectable()
export class CustomHttp extends Http {
  constructor(backend: ConnectionBackend, defaultOptions: RequestOptions) {
    super(backend, defaultOptions);
  }

  request(url: string | Request, options?: RequestOptionsArgs): Observable<Response> {
    (...)
  }

  get(url: string, options?: RequestOptionsArgs): Observable<Response> {
    console.log('get...');
    return super.get(url, options).catch(res => {
      if (res.status === 403) {
        // Set token in options
        return super.get(url, options);
      } else {
        Observable.throw(res);
      }
    });
  }

  (...)
}

If you need to make a request to get the auth token you need to leverage the flatMap operator:

get(url: string, options?: RequestOptionsArgs): Observable<Response> {
  return super.get(url, options).catch(res => {
    if (res.status === 403) {
        return this.getToken().flatMap(token => {
          // Set token in options
          this.setToken(options);
          // Execute again the request
          return super.get(url, options);
        }
      } else {
        Observable.throw(res);
      }
    });