UriBuilder builder = UriBuilder.fromUri(org.keycloak.testsuite.Constants.AUTH_SERVER_ROOT);
URI uri = OpenIDConnectService.grantAccessTokenUrl(builder).build("demo");
WebTarget target = client.target(uri);
String header = BasicAuthHelper.createHeader("customer-portal", "password");
Form form = new Form();
form.param("username", "monkey@redhat.com")
.param("password", "password");
Response response = target.request()
.header(HttpHeaders.AUTHORIZATION, header)
.post(Entity.form(form));
Assert.assertEquals(400, response.getStatus());