Upgrade from v17 to v18

This guide describes the steps to perform an upgrade of the component from version v17 to v18.

Breaking Changes

The component doesn’t work with an older Keycloak version than v25.

Changes

The component requires Kubernetes v1.25 or newer.
Keycloak version is v25.0.6 by default.

Parameter changes

The reverse proxy mode is no longer linked to the ingress mode. Source IPs taken from the Forwarded header as per RFC7239. To use X-Forwarded-* headers see below. You also may consult the Keycloak documentation.

Step-by-step guide

When upgrading the component, the following actions are required if the built-in database is used:

If your setup requires X-Forwarded-* headers rather than Forwarded header as per RFC7239:
```
parameters:
  keycloak:
    helm_values:
      proxy:
        mode: xforwarded
```

Do a backup of the built-in database.

instance=keycloak
namespace=syn-${instance}

kubectl -n "${namespace}" exec -ti keycloak-postgresql-0 -c postgresql -- sh -c 'PGDATABASE="$POSTGRES_DATABASE" PGUSER="$POSTGRES_USER" PGPASSWORD="$POSTGRES_PASSWORD" pg_dump --clean' > keycloak-postgresql-$(date +%F-%H-%M-%S).sql

Apply the parameter changes.
Compile and push the cluster catalog.