CFP: unittest helm chart

[tvonhacht-apple]

Cilium Feature Proposal

Thanks for taking time to make a feature proposal for Cilium! If you have usage questions, please try the slack channel and see the FAQ first.

Is your proposed feature related to a problem?

Making a helm chart change in any of the templates files, can not be tested until actually run against a cluster.
For example this simple change that was done, was hard to debug, because I could only really see rendered templates when deploying it to a cluster. #27229

Describe the feature you'd like

I want to be able to test helm chart locally without needing to run it against a cluster, easily see all areas my change is impacting the chart, as well as being able to validate via a check that no changes in helm-chart without updating snapshots have been done.

Describe your proposed solution

I would like to use helm unittest, a common plugin used for testing helm charts in the open source community.

• write test file in pure YAML
• render locally
• create nothing on your cluster
• wildcard selection for templates
• define values and release options
• snapshot testing
• test suite code completion and validation

Example unittest for `spire/agent/daemonset.yaml

# install/kubernetes/cilium/tests/spire/agent/daemonset.yaml
suite: spire agent daemonset
templates:
  - spire/agent/daemonset.yaml
tests:
  - it: Should not render
    asserts:
      - hasDocuments:
          count: 0

  - it: enabled
    set:
      authentication:
        mutual:
          spire:
            enabled: true
    asserts:
     - matchSnapshot: {}

## This would have been added to test the new flag as added by above PR referenced to test that rendered template with this settings works
  - it: tolerations
    set:
      authentication:
        mutual:
          spire:
            enabled: true
            agent:
              tolerations:
                - operator: Exists
    asserts:
     - matchSnapshot: {}

via helm unittest --update -3 install/kubernetes/cilium/. we could auto generate the snapshots and changes would be part of the PR, easy to review

# install/kubernetes/cilium/tests/snapshots/spire/agent/daemonset.yaml.snap
enabled:
  1: |
    kind: DaemonSet
    metadata:
      name: spire-agent
      # ...
tolerations:
  1: |
    kind: DaemonSet
    metadata:
      name: spire-agent
      # ...
    spec:
      selector:
        matchLabels:
          app: spire-agent
      template:
        metadata:
          namespace: {{ .Values.authentication.mutual.spire.install.namespace }}
          labels:
            app: spire-agent
        spec:
          # ...
          tolerations:
             - operator: Exists

PRB check

helm unittest -3 install/kubernetes/cilium/.

If this is approved, would be happy to create an initial setup with default tests for every object

Once the CFP is close to being finalized, please add it as a PR to the design-cfps repo for final approval.

[github-actions]

This issue has been automatically marked as stale because it has not
had recent activity. It will be closed if no further activity occurs.

[github-actions]

This issue has not seen any activity since it was marked stale.
Closing.