在飞行前响应中，Access-Control-Allow-Headers不允许在Request标头字段中使用cors enable Access-Control-Allow-Origin

Question

I'm using spring boot service for backend and and angular 6 for frontend.

In spring boot i enabled cors using.

 @Override
 public void addCorsMappings(CorsRegistry registry) {
    registry.addMapping("/interview/**").allowedOrigins("*");
 }

and i'm using intercepter for each service.

in frontend calling service:

headers = new Headers();
constructor(private http: Http, private logger: MLogger) {
    this.headers.set("Access-Control-Allow-Origin", "*");
    this.headers.set( 'Content-Type', 'application/json',);
    this.headers.set( 'Accept', '*');
    this.headers.set( 'sessionId', DataService.sessionId);
 }
 private options = new RequestOptions({ headers: this.headers});
  interviewCommand: InterviewCommand;
  getInterviewDetails(data: any): Promise<any> {
    const serviceURL = environment.startInterviewURL;
    return this.http
      .post(serviceURL,data, this.options)
      .toPromise()
      .then(
        interviewCommand => {
          //doing some stuff
          }
        })
      .catch(this.handleInterviewCommandError);
  }

I'm getting below exception if using intercepter. Without using interepter i'm not getting cors error..

Failed to load http://localhost:7070/example/myservice : Request header field Access-Control-Allow-Origin is not allowed by Access-Control-Allow-Headers in preflight response.

In my intercepter i added below thing:

if (request.getMethod().equals("OPTIONS")) {
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Origin-Methods", "GET, POST, OPTIONS");
        response.setHeader("Access-Control-Allow-Headers", "Authorization, Content-Range, Content-Disposition, Content-Description,Origin, X-Requested-With");
        response.setHeader("Access-Control-Expose-Headers", "*");
          response.setHeader("Access-Control-Allow-Credentials", "true");
          response.setHeader("Access-Control-Max-Age", "4800");
        }

Answer 1

Got Answer...

Removed this.headers.set("Access-Control-Allow-Origin", "*") from your frontend

and

added in backend in intercepter response..

response.setHeader("Access-Control-Allow-Headers", "Authorization,Content-Type, Content-Range, Content-Disposition, Content-Description,Origin, X-Requested-With, sessionId"); response.setHeader("Access-Control-Allow-Origin", "*");

When you start playing around with custom request headers you will get a CORS preflight. This is a request that uses the HTTP OPTIONS verb and includes several headers, one of which being Access-Control-Request-Headers listing the headers the client wants to include in the request.

You need to reply to that CORS preflight with the appropriate CORS headers to make this work. One of which is indeed Access-Control-Allow-Headers. That header needs to contain the same values the Access-Control-Request-Headers header contained (or more).

https://fetch.spec.whatwg.org/#http-cors-protocol explains this setup in more detail.

solution is here