Allow passing all database details via `ConfigMap`/`Secret`

[wingsofovnia]

Currently, the chart allow passing database's password from a Secret but not other params like host or username.

Would be great for Helm values to support passing refs to secret/configmaps. Ideally, several syntax options, for example:

    database:
      vendor: postgres
      hostname: 
        configMapKeyRef:
            name: "keycloak-db"
            key: "hostname"
      port: 5432
      database: "my-db"
      username: 
        configMapKeyRef:
            name: "keycloak-db-user"
            key: "username"
      password:
        secretKeyRef:
            name: "keycloak-db-credentials"
            key: "password"

Use Case

I am using cloudnative-pg and db-operator to declaratively define Postgres instance, database and roles for the Keycloak instance. The operators generate a ConfigMap/Secret with connection details.

It will be convenient to just plug those configs into the helm release via helm values.

Workaround

I took inspiration from examples/cloudnative-pg/keycloak-server-values.yaml and provided db connection details from a secret via extraEnv.

⚠️ The example is broken due to dbchecker.enabled: true and unset database.username.

helm-charts/charts/keycloakx/templates/statefulset.yaml

Line 57 in 28fdb97

until printf "." && nc -z -w 2 {{ required ".Values.database.hostname is required if dbchecker is enabled!" .Values.database.hostname }} {{ required ".Values.database.port is required if dbchecker is enabled!" .Values.database.port }}; do

So workaround in general works but with limited functionality.

[evadim]

I use Terraform to create infrastructure in cloud provider so it would be great to use secret with all credentials and provider type.