I have an issue when validating tokens using the keycloak-nodejs-connect library deployed to a kubernetes cluster - specifically when using the internal kubernete's service address for keycloak as the auth-server-url. I am using keycloak version 10.0.1.
Our workflow is as follows - our web app authenticates with a public keycloak client to obtain an access token. This token is attached to requests to the db for data. The db (hasura) uses an auth hook to validate the token before allowing access to its data. This auth hook implements the keycloak-nodejs-connect lib and through the provided middleware calls the grantManager's validateToken. However when the connect lib is configured with kubernete's service address (http://keycloak:8080/auth/) it is guaranteed to error on the issuer match because the issuer property in the JWT token (iss) will be the frontend url configured in the keycloak server (https://keycloak.public.address.uk/auth/).
Is there a way to provide a frontend and backend url to the keycloak-nodejs-connect library so that the issuer validation can occur whilst using the backend url to speak to keycloak via a kubernete's service - or should I be configuring keycloak a certain way so that the issuer is different? I am specifically needing to use a kubernete's service address here rather than a public address for keycloak communications in my cluster.
The following source location hyperlinks try to highlight the issue in code:
Many thanks for any help, Andy.