Generic Helm Chart

A generic, reusable Helm chart for deploying Java operators built with JOSDK is available at helm/generic-helm-chart.

It is intended as a template for operator developers — a starting point that covers common deployment patterns so you don’t have to write a chart from scratch. The chart is maintained on a best-effort basis. Contributions are more than welcome.

The chart is used in the operations sample operator E2E test to deploy the operator to a cluster via Helm.

What the Chart Provides

• Deployment with security defaults (non-root user, read-only filesystem, no privilege escalation)
• Dynamic RBAC (ClusterRole, ClusterRoleBinding, ServiceAccount) — permissions are generated automatically from the primary and secondary resources you declare in values.yaml
• ConfigMap for operator configuration (config.yaml) and logging (log4j2.xml), mounted at /config
• Leader election support (opt-in)
• Extensibility via extra containers, init containers, volumes, and environment variables

Key Configuration

The most important values to set when adapting the chart for your operator:

image:
  repository: my-operator-image   # required
  tag: "latest"

# Custom resources your operator reconciles
primaryResources:
  - apiGroup: "sample.javaoperatorsdk"
    resources:
      - myresources

# Kubernetes resources your operator manages
secondaryResources:
  - apiGroup: ""
    resources:
      - configmaps
      - services

Primary resources get read/watch/patch permissions and status sub-resource access. Secondary resources get full CRUD permissions. Default verbs can be overridden per resource entry.

The ClusterRole always grants get, create and patch on events in the core API group, so recording events works without any extra configuration. All three are needed: an event is looked up by name before it is created, so that recording the same event again resolves to the event already recorded, and that event is then patched to count the new occurrence rather than recorded again. See Events for what this means if you write your own RBAC.

Operator Environment

The chart injects OPERATOR_NAMESPACE automatically. You can optionally set WATCH_NAMESPACE to restrict the operator to a single namespace, and add arbitrary environment variables:

operator:
  watchNamespace: ""       # empty = all namespaces
  env:
    - name: MY_CUSTOM_VAR
      value: "some-value"

Resource Defaults

resources:
  limits:
    cpu: 500m
    memory: 512Mi
  requests:
    cpu: 100m
    memory: 128Mi

See the full values.yaml for all available options.

Usage Example

A working example of how to use the chart can be found in the operations sample operator’s helm-values.yaml:

image:
  repository: operations-operator
  pullPolicy: Never
  tag: "latest"

nameOverride: "operations-operator"

resources: {}

primaryResources:
  - apiGroup: "sample.javaoperatorsdk"
    resources:
      - metricshandlingcustomresource1s
      - metricshandlingcustomresource2s

Install with:

helm install my-operator ./helm/generic-helm-chart -f my-values.yaml --namespace my-ns

Testing the Chart

The chart includes unit tests using the helm-unittest plugin. Run them with:

./helm/run-tests.sh