You can set them in a response wrapper (io.undertow.server.HttpServerExchange#addResponseWrapper) and they should not be overriden, although this is not ideal.

If you file a JIRA I will look at adding better support for this into the proxy.

Stuart

----- Original Message -----
> From: "Jeff Williams" <jeffw@wherethebitsroam.com>
> To: undertow-dev@lists.jboss.org
> Sent: Saturday, 1 November, 2014 12:43:38 AM
> Subject: [undertow-dev] Changing headers on proxy response
>
> Hi,
>
> I am currently using a customer handler wrapping the proxy handler. I want to
> set some response headers from my handler, but if they exist in the response
> from the proxy's backend, they are overridden. Example code:
>
> Undertow.builder()
> .addHttpListener(8080, "localhost")
> .setHandler(new MyHandler(new ProxyHandler(proxy, 30000, ResponseCodeHandler.
> HANDLE_404 ))).build();
>
> class MyHandler extends HttpHandler {
> private static final HttpString ACCESS_CONTROL_EXPOSE_HEADERS = new
> HttpString("Access-Control-Expose-Headers");
> private HTTPHandler next;
> public MyHandler(HttpHandler next) {
> this.next = next;
> }
> p ublic void handleRequest(HttpServerExchange exchange ) throws Exception {
> exchange .getResponseHeaders().put( ACCESS_CONTROL_EXPOSE_HEADERS , " new
> ACEH" );
> }
> }
>
> The problem here is that the backend server responds with an
> Access-Control-Expose-Headers header and that replaces the one I set in
> MyHandler.
>
> Is there any way I can change headers after proxy has received the response
> from backend and before it starts sending the response to the client?
>
> Regards,
> Jeff
>
>
> _______________________________________________
> undertow-dev mailing list
> undertow-dev@lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/undertow-dev