Keycloak for preflight is invalid (redirect)

Question

I'm having an error about preflight when I try to reach a rest api.

error XMLHttpRequest cannot load http://localhost:8080/hello. Response for preflight is invalid (redirect)

I made those filters which I need in order to access the api from javascript which is served from another port. I guess they are the culprit. I tried adding authorization as well as Authorization capitalizaed but it still gives me the error.

filter:

@Override
public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext) throws IOException {
        responseContext.getHeaders().add("Access-Control-Allow-Origin", "*");
        responseContext.getHeaders().add("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
        responseContext.getHeaders().add("Access-Control-Max-Age", "-1");
        responseContext.getHeaders().add("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, Authorization");
}

headers

Accept:*/*
Accept-Encoding:gzip, deflate, sdch, br
Accept-Language:en-US,en;q=0.8,fr;q=0.6
Access-Control-Request-Headers:authorization
Access-Control-Request-Method:GET
Cache-Control:no-cache
Connection:keep-alive
Host:localhost:8080
Origin:http://localhost:4200
Pragma:no-cache
Referer:http://localhost:4200/
User-Agent:Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36