Operator SDK – Reference for Helm-based Operators

Docs: Proxy Friendly Operators

Mon, 01 Jan 0001 00:00:00 +0000

Proxy-friendly Operators should inspect their environment for the standard proxy variables (HTTPS_PROXY, HTTP_PROXY, and NO_PROXY) and pass the values to Operands.

This can be accomplished by modifying the watches.yaml to include the overrides based on an environment variable:

- group: demo.example.com
  version: v1alpha1
  kind: Nginx
  chart: helm-charts/nginx
  overrideValues:
    proxy.http: $HTTP_PROXY
#+kubebuilder:scaffold:watch

Note: This example assumes that proxy.http is included in your chart’s Values.yaml. The nginx tutorial does not have this value, but you can add to the helmcharts/nginx/Values.yaml:

proxy:
  http: ""
  https: ""
  no_proxy: ""

You will also need to make sure the chart template supports the usage of these values. Using the nginx tutorial, edit helm-charts/nginx/templates/deployment.yaml

containers:                                                                                                                                                                                                                             
  - name: {{ .Chart.Name }}                                                                                                                                                                                                             
    securityContext:                                                                                                                                                                                                                    
      {{- toYaml .Values.securityContext | nindent 12 }}                                                                                                                                                                                
    image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"                                                                                                                                         
    imagePullPolicy: {{ .Values.image.pullPolicy }}                                                                                                                                                                                     
    env:                                                                                                                                                                                                                                
      - name: http_proxy                                                                                                                                                                                                                
        value: "{{ .Values.proxy.http }}"

You can set the environment variable on the Operator deployment. Using the nginx tutorial, edit config/manager/manager.yaml:

containers:
 - args:
   - --leader-elect
   - --leader-election-id=helm-proxy-demo
   image: controller:latest
   name: manager
   env:
     - name: "HTTP_PROXY"
       value: "http_proxy_test"

Docs: Define Watches in Helm-based operators

Mon, 01 Jan 0001 00:00:00 +0000

The Watches file contains a list of mappings from custom resources, identified by it’s Group, Version, and Kind, to a Helm chart. The Operator expects this mapping file in a predefined location: /opt/helm/watches.yaml

The follow tables describes the fields in an entry in watches.yaml:

Field	Description
group	The group of the Custom Resource that you will be watching.
version	The version of the Custom Resource that you will be watching.
kind	The kind of the Custom Resource that you will be watching.
chart	The path to the helm chart to use when reconciling this GVK.
watchDependentResources	Enable watching resources that are created by helm (default: `true`).
overrideValues	Values to be used for overriding Helm chart’s defaults. For additional information see the reference doc.
selector	The conditions that a resource’s labels must satisfy in order to get reconciled. For additional information see labels and selectors documentation.
dryRunOption	The helm dry-run method to use when comparing manifests. Set to `server` to ensure `lookup()` functions are evaluated (default: `client/none`)

For reference, here is an example of a simple watches.yaml file:

# Use the 'create api' subcommand to add watches to this file.
- group: foo.example.com
  version: v1alpha1
  kind: Foo
  chart: helm-charts/foo
  overrideValues:
    image.repository: quay.io/mycustomrepo
  watchDependentResources: false
  selector:
    matchExpressions:
     - {key: testLabel, operator: Exists, values: []}
  dryRunOption: server

Docs: Advanced Features of Helm-based Operators

Mon, 01 Jan 0001 00:00:00 +0000