I'm trying to use Keycloack as a SAML server. I deployed my keycloack (v21.1.2) instance with:
docker run --name keycloak_dev2 -p 8089:8080 \
-e KEYCLOAK_ADMIN=admin -e KEYCLOAK_ADMIN_PASSWORD=admin \
quay.io/keycloak/keycloak:latest \
start-dev --hostname-url=http://localhost:8089
I set up a realm and client with type SAML and various configs that seem fairly basic (can share more if that's useful).
I'm able to get my Python application to redirect to keycloack, am able to login, but in the process of getting redirected back to my application, I get a 500 and the keycloack server has this error:
Uncaught server error: java.lang.RuntimeException: empty host name
The call that triggers this is:
http://localhost:8089/realms/<REALM_NAME>/protocol/saml?SAMLRequest=<LONG_KEY_HERE>&RelayState=<APPLICATION_URL>
I've tried specifying all kinds of options to the docker run command (KC_HOSTNAME, --hostname, etc...) and I still get the same error. I can't find anything online about why this error is showing up. Does anyone have any ideas?