In order for the client to be able to read cookies from cross-origin requests, you need to have:
All responses from the server need to have the following in their header:
Access-Control-Allow-Credentials: true
The client needs to send all requests with withCredentials: true
option
In my implementation with Angular 7 and Spring Boot, I achieved that with the following:
Server-side:
@CrossOrigin(origins = "http://my-cross-origin-url.com", allowCredentials = "true")
@Controller
@RequestMapping(path = "/something")
public class SomethingController {
...
}
The origins = "http://my-cross-origin-url.com"
part will add Access-Control-Allow-Origin: http://my-cross-origin-url.com
to every server's response header
The allowCredentials = "true"
part will add Access-Control-Allow-Credentials: true
to every server's response header, which is what we need in order for the client to read the cookies
Client-side:
import { HttpInterceptor, HttpXsrfTokenExtractor, HttpRequest, HttpHandler, HttpEvent } from "@angular/common/http";
import { Injectable } from "@angular/core";
import { Observable } from 'rxjs';
@Injectable()
export class CustomHttpInterceptor implements HttpInterceptor {
constructor(private tokenExtractor: HttpXsrfTokenExtractor) {
}
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
// send request with credential options in order to be able to read cross-origin cookies
req = req.clone({ withCredentials: true });
// return XSRF-TOKEN in each request's header (anti-CSRF security)
const headerName = 'X-XSRF-TOKEN';
let token = this.tokenExtractor.getToken() as string;
if (token !== null && !req.headers.has(headerName)) {
req = req.clone({ headers: req.headers.set(headerName, token) });
}
return next.handle(req);
}
}
With this class you actually inject additional stuff to all your request.
The first part req = req.clone({ withCredentials: true });
, is what you need in order to send each request with withCredentials: true
option. This practically means that an OPTION request will be send first, so that you get your cookies and the authorization token among them, before sending the actual POST/PUT/DELETE requests, which need this token attached to them (in the header), in order for the server to verify and execute the request.
The second part is the one that specifically handles an anti-CSRF token for all requests. Reads it from the cookie when needed and writes it in the header of every request.
The desired result is something like this: