Job

---
apiVersion: batch/v1
kind: Job
metadata:
  name: "{{.Release.Name}}-secrets-generator-pre-install-job"
  labels:
    heritage: {{.Release.Service | quote }}
    release: {{.Release.Name | quote }}
    chart: "{{.Chart.Name}}-{{.Chart.Version}}"
  annotations:
    "helm.sh/hook": pre-install,pre-upgrade
    "helm.sh/hook-weight": "-5"
    "helm.sh/hook-delete-policy": before-hook-creation
spec:
  template:
    metadata:
      name: "{{.Release.Name}}-secrets-generator-pre-install-job"
      labels:
        heritage: {{.Release.Service | quote }}
        release: {{.Release.Name | quote }}
        chart: "{{.Chart.Name}}-{{.Chart.Version}}"
    spec:
      restartPolicy: Never
      serviceAccountName: {{.Release.Name}}-secrets-generator-sa
      containers:
      - name: secrets-generator
        image: "{{ .Values.graylog.secretsGenerator.image.repository }}:{{ .Values.graylog.secretsGenerator.image.tag }}"
        imagePullPolicy: {{ .Values.graylog.secretsGenerator.image.pullPolicy }}
        command:
        - /bin/bash
        - -ec
        - |
          kubectl -n {{ .Release.Namespace }} get secret {{ template "graylog.fullname" . }}-secrets > /dev/null 2>&1 && echo "{{ template "graylog.fullname" . }}-secrets exist" || echo "$SECRET"  | kubectl -n {{ .Release.Namespace }} create -f -
        env:
        - name: SECRET
          value: |
{{ tpl (.Files.Get "resources/secrets.yaml") . | indent 12 }}

RoleBinding

apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: {{.Release.Name}}-secrets-generator-rolebinding
  labels:
    heritage: {{.Release.Service | quote }}
    release: {{.Release.Name | quote }}
    chart: "{{.Chart.Name}}-{{.Chart.Version}}"
  annotations:
    "helm.sh/hook": pre-install,pre-upgrade
    "helm.sh/hook-weight": "-10"
    "helm.sh/hook-delete-policy": before-hook-creation
  namespace: {{ .Release.Namespace }}
subjects:
- kind: ServiceAccount
  name: {{.Release.Name}}-secrets-generator-sa
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: {{.Release.Name}}-secrets-generator-role

resources/secrets.yaml

{{- $graylogPasswordSecret := randAlphaNum 128 }}
{{- $graylogAdminPassword := randAlphaNum 64 }}
---
apiVersion: v1
kind: Secret
metadata:
  annotations:
    "helm.sh/resource-policy": keep
  name: {{ template "graylog.fullname" . }}-secrets
  labels:
    configVersion: v1
    app: {{ template "graylog.name" . }}
    chart: {{ template "graylog.chart" . }}
    release: {{ .Release.Name }}
    heritage: {{ .Release.Service }}
type: Opaque
data:
  GRAYLOG_PASSWORD_SECRET: {{ $graylogPasswordSecret | b64enc | quote }}
  GRAYLOG_ROOT_PASSWORD_SHA2: {{ $graylogAdminPassword | sha256sum | b64enc | quote }}
  GRAYLOG_ADMIN_PASSWORD: {{ $graylogAdminPassword | b64enc | quote }}