Unable to integrate knox with keycloak

Hello Team,
I am trying to integrate Knox with existing keycloak setup and have started knox gateway at 8443. However, facing issues while integration with Keycloak.
1. Unable to generate sp-metadata.xml file
2. Getting below error while accessing https://host:8443/gateway/keycloak/api/v1/websso

Referring http://example.com https://metalop.com/2019/07/10/securing-hadoop-big-data-landscape-with-apache-knox-gateway-and-keycloak-part-4-configuring-knox-to-authenticate-with-keycloak/].

Please help to resolve the issue.