Incorrect hard-coded database host when using Bitnami subcharts

Describe your Issue

When using an external database, if either of the Bitnami subcharts for MariaDB or PostgreSQL are set up in replication mode, the Nextcloud init container will fail because it's using a hard-coded DB hostname value: --host=%s-mariadb or -h %s-postgresql. Neither of these take into account the fact that if you enable replication on the Bitnami MariaDB chart, for example, it creates service names nextcloud-mariadb-primary and nextcloud-mariadb-secondary, but no nextcloud-mariadb, as expected by the mariadb-isalive container.

Logs and Errors

The mariadb-isalive container in the nextcloud-* pods get stuck with these logs repeating ad infinitum:

ERROR 2005 (HY000): Unknown server host 'nextcloud-mariadb' (-2)
waiting for mysql

Describe your Environment

• Kubernetes distribution: confirmed on both EKS and baremetal

• Helm Version (or App that manages helm): ArgoCD v2.7.3 running Helm v3.11.2 (EKS) and Helm v3.12.0 (baremetal)

• Helm Chart Version: 3.5.13

• values.yaml:

# --------------------------------------------------------------------------- #
# Nextcloud                                                                   #
# --------------------------------------------------------------------------- #

nextcloud:
  host: nextcloud.[REDACTED]
  existingSecret:
    enabled: true
    secretName: nextcloud-secrets
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 1
  securityContext:
    runAsUser: 1020
    runAsGroup: 1005
    runAsNonRoot: true

# --------------------------------------------------------------------------- #
# Database                                                                    #
# --------------------------------------------------------------------------- #

internalDatabase:
  enabled: false

externalDatabase:
  enabled: true
  type: mysql
  host: nextcloud-mariadb-primary
  database: nextcloud
  existingSecret:
    secretName: nextcloud-secrets
    usernameKey: mariadb-username
    passwordKey: mariadb-password

mariadb:
  enabled: true
  auth:
    database: nextcloud
    username: nextcloud
    existingSecret: nextcloud-secrets
  architecture: replication
  primary:
    persistence:
      enabled: true
      existingClaim: nextcloud-mariadb-persistence
      storageClass: ceph-block
      accessMode: ReadWriteOnce
      size: 8Gi

# --------------------------------------------------------------------------- #
# Redis                                                                       #
# --------------------------------------------------------------------------- #

redis:
  enabled: true
  clusterDomain: [REDACTED (NON-DEFAULT)]
  auth:
    enabled: true
    existingSecret: nextcloud-secrets
    existingSecretPasswordKey: redis-password

# --------------------------------------------------------------------------- #
# Resources                                                                   #
# --------------------------------------------------------------------------- #

resources:
  requests:
    cpu: 500m
    memory: 1Gi
  limits:
    cpu: 1000m
    memory: 2Gi

# --------------------------------------------------------------------------- #

Additional context, if any

I did set the value of externalDatabase.host to the correct service name nextcloud-mariadb-primary, but this still fails because these lines in _helpers.tpl are overwriting it:

 76  {{- else if .Values.mariadb.enabled }}
 77  - name: MYSQL_HOST
 78    value: {{ template "mariadb.primary.fullname" .Subcharts.mariadb }}
...
126    {{- else }}
127  - name: MYSQL_HOST
128    value: {{ .Values.externalDatabase.host | quote }}

Start in charts/nextcloud/templates/_helpers.tpl around lines 76-128, where MYSQL_HOST is selected, and compare the generated environment with the externalDatabase.host value in the reported values.yaml. Use Helm rendering with MariaDB and PostgreSQL replication enabled; done means the init container uses an available replication service hostname instead of the nonexistent hard-coded base name.