Testing a Plugin

Plugin Testing Requirements

All plugins contributed to plugin-extensions repository should include comprehensive Helm Chart Tests using the bats/bats-detik testing framework. This ensures our plugins are robust, deployable, and catch potential issues early in the development cycle.

What is bats/bats-detik?

The bats/bats-detik framework simplifies end-to-end (e2e) Testing in Kubernetes. It combines the Bash Automated Testing System (bats) with Kubernetes-specific assertions (detik). This allows you to write test cases using natural language-like syntax, making your tests easier to read and maintain.

Implementing Tests

1. Create a /tests folder inside your Plugin’s Helm Chart templates folder to store your test resources.

2. ConfigMap definition:

   • Create a test-<plugin-name>-config.yaml file in the templates/tests directory to define a ConfigMap that will hold your test script.
   • This ConfigMap contains the test script run.sh that will be executed by the test Pod to run your tests.

{{- if .Values.testFramework.enabled -}}
apiVersion: v1
kind: ConfigMap
metadata:
  name: {{ .Release.Name }}-test
  namespace: {{ .Release.Namespace }}
  labels:
    type: integration-test
  annotations:
    "helm.sh/hook": test
    "helm.sh/hook-weight": "-5" # Installed and upgraded before the test pod
    "helm.sh/hook-delete-policy": "before-hook-creation,hook-succeeded"
data:
  run.sh: |-

    #!/usr/bin/env bats

    load "/usr/lib/bats/bats-detik/utils"
    load "/usr/lib/bats/bats-detik/detik"

    DETIK_CLIENT_NAME="kubectl"

    @test "Verify successful deployment and running status of the {{ .Release.Name }}-operator pod" {
        verify "there is 1 deployment named '{{ .Release.Name }}-operator'"
        verify "there is 1 service named '{{ .Release.Name }}-operator'"
        try "at most 2 times every 5s to get pods named '{{ .Release.Name }}-operator' and verify that '.status.phase' is 'running'"
    }

    @test "Verify successful creation and bound status of {{ .Release.Name }} persistent volume claims" {
        try "at most 3 times every 5s to get persistentvolumeclaims named '{{ .Release.Name }}.*' and verify that '.status.phase' is 'Bound'"
    }

    @test "Verify successful creation and available replicas of {{ .Release.Name }} Prometheus resource" {
        try "at most 3 times every 5s to get prometheuses named '{{ .Release.Name }}' and verify that '.status.availableReplicas' is more than '0'"
    }

    @test "Verify creation of required custom resource definitions (CRDs) for {{ .Release.Name }}" {
        verify "there is 1 customresourcedefinition named 'prometheuses'"
        verify "there is 1 customresourcedefinition named 'podmonitors'"
    }
{{- end -}}

Note: You can use this guide for reference when writing your test assertions.

3. Test Pod Definition:

   • Create a test-<plugin-name>.yaml file in the templates/tests directory to define a Pod that will run your tests.
   • This test Pod will mount the ConfigMap created in the previous step and will execute the test script run.sh.

{{- if .Values.testFramework.enabled -}}
apiVersion: v1
kind: Pod
metadata:
  name: {{ .Release.Name }}-test
  namespace: {{ .Release.Namespace }}
  labels:
    type: integration-test
  annotations:
    "helm.sh/hook": test
    "helm.sh/hook-delete-policy": "before-hook-creation,hook-succeeded"
spec:
  serviceAccountName: {{ .Release.Name }}-test
  containers:
    - name: bats-test
      image: "{{ .Values.testFramework.image.registry}}/{{ .Values.testFramework.image.repository}}:{{ .Values.testFramework.image.tag }}"
      imagePullPolicy: {{ .Values.testFramework.image.pullPolicy }}
      command: ["bats", "-t", "/tests/run.sh"]
      volumeMounts:
        - name: tests
          mountPath: /tests
          readOnly: true   volumes:
    - name: tests
      configMap:
        name: {{ .Release.Name }}-test
  restartPolicy: Never
{{- end -}}

4. RBAC Permissions:

• Create the necessary RBAC resources in the templates/tests folder with a dedicated ServiceAccount and role authorisations so that the test Pod can cover test the cases.
• You can use test-permissions.yaml from the kube-monitoring as a reference to configure RBAC permissions for your test Pod.

5. Configure the Test Framework in Plugin’s values.yaml:
   • Add the following configuration to your Plugin’s values.yaml file:

testFramework:
  enabled: true
  image:
    registry: ghcr.io
    repository: cloudoperators/greenhouse-extensions-integration-test
    tag: main
  imagePullPolicy: IfNotPresent

6. Running the Tests:

Important: Once you have completed all the steps above, you are ready to run the tests. However, before running the tests, ensure that you perform a fresh Helm installation or upgrade of your Plugin’s Helm release against your test Kubernetes cluster (for example, Minikube or Kind) by executing the following command:

# For a new installation
helm install <Release name> <chart-path>

# For an upgrade
helm upgrade <Release name> <chart-path>

• After the Helm installation or upgrade is successful, run the tests against the same test Kubernetes cluster by executing the following command.

helm test <Release name>

Contribution Checklist

Before submitting a pull request:

• Ensure your Plugin’s Helm Chart includes a /tests directory.
• Verify the presence of test-<plugin-name>.yaml, test-<plugin-name>-config.yaml, and test-permissions.yaml files.
• Test your Plugin thoroughly using helm test <release-name> and confirm that all tests pass against a test Kubernetes cluster.
• Include a brief description of the tests in your pull request.
• Make sure that your Plugin’s Chart Directory and the Plugin’s Upstream Chart Repository are added to this greenhouse-extensions helm test config file. This will ensure that your Plugin’s tests are automatically run in the GitHub Actions workflow when you submit a pull request for this Plugin.

Important Notes

• Test Coverage: Aim for comprehensive test coverage to ensure your Plugin’s reliability.
• Test Isolation: Design tests that don’t interfere with other plugins or production environments.