Add envtest for testing controllers (k0smotron#806)

Signed-off-by: Adrian Pedriza <[email protected]>
Co-authored-by: Adrian Pedriza <[email protected]>

cmd/main.go

@@ -231,7 +231,6 @@ func main() {
 
 		if err = (&controlplane.K0sController{
 			Client:     mgr.GetClient(),
-			Scheme:     mgr.GetScheme(),
 			ClientSet:  clientSet,
 			RESTConfig: restConfig,
 		}).SetupWithManager(mgr); err != nil {

docs/contributing/contribute-testing.md

@@ -1,70 +1,22 @@
 # Testing guidelines
 
-k0smotron uses GitHub actions to run automated tests on all pull requests prior to merging.
-Pull request will not be reviewed before all tests are green,
-so to save time and prevent your Pull request from going stale,
-it is best to test it before submitting the pull request.
+K0smotron follows a comprehensive testing strategy that includes unit, integration, and e2e testing to ensure the reliability and robustness of the system.
 
-## Run local verifications
+All unit, integration, and e2e tests are executed automatically on pull requests that are intended to be merged, ensuring that changes are thoroughly validated before integration into the main codebase. These tests are executed using [GitHub Actions](https://docs.github.com/en/actions), which provides a seamless and automated way to validate proposed changes. This layered approach ensures that proposed changes are both correct and meet the expected quality standards.
 
-Run the following style and formatting commands to fix or check-in the changes:
+For details on the contribution process, including how to follow the GitHub workflow and ensure your changes pass all necessary validations, please refer to the [Contributing Workflow](contribute-workflow.md).
 
-1. Verify code style using [`golangci-lint`](https://golangci-lint.run/). In the root directory of the repository run:
+## Unit and Integration Testing
 
-   ```shell
-   make lint
-   ```
+In k0smotron project, tests are prioritized to execute quickly in order to maintain a fast feedback loop, ensuring efficient and agile development.
 
-   The build system automatically installs `golangci-lint`.
+K0smotron uses [go test](https://pkg.go.dev/testing) as the foundation for all our tests, combined with the [testify](https://pkg.go.dev/github.com/stretchr/testify) library to simplify assertions and improve test readability and reliability. Both unit and integration tests rely on this approach to ensure consistency and ease of development.
 
-2. Format Go source code using the `go fmt` command:
+- **Unit Testing**: Focused on isolated components, unit tests validate the correctness of individual functions or methods in a controlled environment, ensuring they behave as expected.
 
+- **Integration Testing**: For integration testing, k0smotron uses [envtest](https://pkg.go.dev/sigs.k8s.io/controller-runtime/pkg/envtest), which provides a lightweight Kubernetes control plane with the essential components needed to test interactions between the code and Kubernetes API. This approach allows us to validate the behavior of our controllers and other Kubernetes integrations in a reproducible and efficient manner without requiring a full cluster. 
 
-   ```shell
-   go fmt ./...
-   ```
+  Following the best practices suggested in the [Cluster API documentation](https://cluster-api.sigs.k8s.io/developer/core/testing), integration tests are written using [**generic infrastructure providers**](https://cluster-api.sigs.k8s.io/developer/core/testing#generic-providers) rather than a specific provider. This ensures that tests remain agnostic and reusable across different infrastructures, fostering better maintainability and adaptability.
 
-3. Check documentation.
-
-   The Dockerized setup is used to locally perform documentation tests.
-   Run `make docs-serve-dev` to build documentation on http://localhost:8000.
-
-   If your port `8000` is busy, run `make docs-serve-dev DOCS_DEV_PORT=9999`.
-   The documentation page will be available on http://localhost:9999.
-
-4. Pre-submit flight checks.
-
-   In the repository root directory, ensure that the following commands are successfully run:
-
-    * `make build && git diff --exit-code`
-      This command verifies that the build is working
-      and that the generated source code matches the code checked into source control.
-    * `make test`
-      This command verifies that all the unit tests pass.
-
-   Once all tests have passed, you can open a pull request upstream.
-
-## Open pull request
-
-### Draft mode
-
-If you open a pull request in draft mode, it will only go through the automated testing.
-Once you decide the PR is ready for review, transition it out of draft mode to notify the k0smotron team.
-
-### Pre-requisites for merge
-
-In order for a pull request to be merged, the following conditions should be met:
-
-1. The PR has passed all the automated tests (style, build and conformance tests).
-1. All the PR commits have been signed with the `--signoff` option.
-1. The PR has been reviewed and approved by a code owner.
-1. The PR has been rebased against upstream main branch.
-
-## Cleanup local workspace
-
-Run `make clean` to remove all the intermediate files and directories created
-locally during the k0smotron build.
-You cannot use `git clean -X` or `rm -rf`, since the Go modules
-cache sets all of its subdirectories to read-only.
-If you encounter problems during a deletion process,
-run `chmod -R u+w /path/to/workspace && rm -rf /path/to/workspace`.
+## E2E testing
+TBD

docs/contributing/contribute-workflow.md

@@ -64,6 +64,41 @@ Create pull requests to contribute to [k0smotron GitHub repository](http://githu
     Too many commits make the history messy and violate the principle
     that commits ought to be individually understandable and useful.
 
+## Run local verifications
+
+Run the following style and formatting commands to fix or check-in the changes:
+
+1. Verify code style using [`golangci-lint`](https://golangci-lint.run/). In the root directory of the repository run:
+```shell
+make lint
+```
+The build system automatically installs `golangci-lint`.
+
+2. Format Go source code using the `go fmt` command:
+```shell
+go fmt ./...
+```
+
+3. Check documentation.
+
+   The Dockerized setup is used to locally perform documentation tests.
+   Run `make docs-serve-dev` to build documentation on http://localhost:8000.
+
+   If your port `8000` is busy, run `make docs-serve-dev DOCS_DEV_PORT=9999`.
+   The documentation page will be available on http://localhost:9999.
+
+4. Pre-submit flight checks.
+
+   In the repository root directory, ensure that the following commands are successfully run:
+
+    * `make build && git diff --exit-code`
+      This command verifies that the build is working
+      and that the generated source code matches the code checked into source control.
+    * `make test`
+      This command verifies that all the unit tests pass.
+
+   Once all tests have passed, you can open a pull request upstream.
+
 ## Commit and push
 
 Commit and sign your changes:
@@ -104,6 +139,20 @@ git push --set-upstream my_fork my_feature_branch
 
 Refer to the official GitHub documentation [Creating a pull request from a fork](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request-from-a-fork).
 
+### Draft mode
+
+If you open a pull request in draft mode, it will only go through the automated testing.
+Once you decide the PR is ready for review, transition it out of draft mode to notify the k0smotron team.
+
+### Pre-requisites for merge
+
+In order for a pull request to be merged, the following conditions should be met:
+
+1. The PR has passed all the automated tests (style, build and conformance tests).
+1. All the PR commits have been signed with the `--signoff` option.
+1. The PR has been reviewed and approved by a code owner.
+1. The PR has been rebased against upstream main branch.
+
 ### Wait for code review
 
 The k0smotron team will review your pull request and leave comments.
@@ -127,3 +176,12 @@ git push --force
 ```
 
 If necessary, you can run multiple iteration of `rebase`/`push -f`.
+
+## Cleanup local workspace
+
+Run `make clean` to remove all the intermediate files and directories created
+locally during the k0smotron build.
+You cannot use `git clean -X` or `rm -rf`, since the Go modules
+cache sets all of its subdirectories to read-only.
+If you encounter problems during a deletion process,
+run `chmod -R u+w /path/to/workspace && rm -rf /path/to/workspace`.

go.mod

@@ -5,6 +5,7 @@ go 1.22.0
 require (
 	github.com/cloudflare/cfssl v1.6.4
 	github.com/go-logr/logr v1.4.2
+	github.com/gobuffalo/flect v1.0.2
 	github.com/google/uuid v1.6.0
 	github.com/imdario/mergo v0.3.16
 	github.com/k0sproject/k0s v1.27.2-0.20230504131248-94378e521a29
@@ -16,8 +17,11 @@ require (
 	github.com/stretchr/testify v1.9.0
 	gopkg.in/yaml.v3 v3.0.1
 	k8s.io/api v0.30.3
+	k8s.io/apiextensions-apiserver v0.30.3
 	k8s.io/apimachinery v0.30.3
 	k8s.io/client-go v0.30.3
+	k8s.io/klog/v2 v2.120.1
+	k8s.io/kubectl v0.30.3
 	k8s.io/kubernetes v1.30.3
 	k8s.io/utils v0.0.0-20240502163921-fe8a2dddb1d0
 	sigs.k8s.io/controller-runtime v0.18.5
@@ -57,7 +61,7 @@ require (
 	github.com/xeipuuv/gojsonschema v1.2.0 // indirect
 	golang.org/x/crypto v0.27.0
 	golang.org/x/sync v0.8.0 // indirect
-	golang.org/x/tools v0.24.0 // indirect
+	golang.org/x/tools v0.24.0
 	gotest.tools/v3 v3.4.0 // indirect
 	helm.sh/helm/v3 v3.11.3 // indirect
 	k8s.io/kube-aggregator v0.27.2 // indirect
@@ -90,7 +94,6 @@ require (
 	github.com/go-openapi/jsonreference v0.20.2 // indirect
 	github.com/go-openapi/swag v0.22.3 // indirect
 	github.com/go-task/slim-sprig/v3 v3.0.0 // indirect
-	github.com/gobuffalo/flect v1.0.2 // indirect
 	github.com/gofrs/uuid v4.4.0+incompatible // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
@@ -152,6 +155,7 @@ require (
 	go.uber.org/multierr v1.11.0 // indirect
 	go.uber.org/zap v1.27.0 // indirect
 	golang.org/x/exp v0.0.0-20240719175910-8a7402abbf56 // indirect
+	golang.org/x/mod v0.20.0 // indirect
 	golang.org/x/net v0.28.0 // indirect
 	golang.org/x/oauth2 v0.21.0 // indirect
 	golang.org/x/sys v0.25.0 // indirect
@@ -166,14 +170,12 @@ require (
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/natefinch/lumberjack.v2 v2.2.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
-	k8s.io/apiextensions-apiserver v0.30.3 // indirect
 	k8s.io/apiserver v0.30.3 // indirect
 	k8s.io/cloud-provider v0.27.1 // indirect
 	k8s.io/cluster-bootstrap v0.30.3 // indirect
 	k8s.io/component-base v0.30.3 // indirect
 	k8s.io/component-helpers v0.30.3 // indirect
 	k8s.io/controller-manager v0.30.3 // indirect
-	k8s.io/klog/v2 v2.120.1 // indirect
 	k8s.io/kms v0.30.3 // indirect
 	k8s.io/kube-openapi v0.0.0-20240228011516-70dd3763d340 // indirect
 	k8s.io/kubelet v0.27.1 // indirect

go.sum

@@ -521,6 +521,8 @@ k8s.io/kube-aggregator v0.30.3 h1:hy5zfQ7p6BuJgc/XtGp3GBh2MPfOj6b1n3raKKMHOQE=
 k8s.io/kube-aggregator v0.30.3/go.mod h1:2SP0IckvQoOwwZN8lmtWUnTZTgIpwOWvidWtxyqLwuk=
 k8s.io/kube-openapi v0.0.0-20240228011516-70dd3763d340 h1:BZqlfIlq5YbRMFko6/PM7FjZpUb45WallggurYhKGag=
 k8s.io/kube-openapi v0.0.0-20240228011516-70dd3763d340/go.mod h1:yD4MZYeKMBwQKVht279WycxKyM84kkAx2DPrTXaeb98=
+k8s.io/kubectl v0.30.3 h1:YIBBvMdTW0xcDpmrOBzcpUVsn+zOgjMYIu7kAq+yqiI=
+k8s.io/kubectl v0.30.3/go.mod h1:IcR0I9RN2+zzTRUa1BzZCm4oM0NLOawE6RzlDvd1Fpo=
 k8s.io/kubelet v0.30.3 h1:KvGWDdhzD0vEyDyGTCjsDc8D+0+lwRMw3fJbfQgF7ys=
 k8s.io/kubelet v0.30.3/go.mod h1:D9or45Vkzcqg55CEiqZ8dVbwP3Ksj7DruEVRS9oq3Ys=
 k8s.io/kubernetes v1.30.3 h1:A0qoXI1YQNzrQZiff33y5zWxYHFT/HeZRK98/sRDJI0=

internal/controller/controlplane/helper.go

@@ -50,7 +50,7 @@ func (c *K0sController) createMachine(ctx context.Context, name string, cluster
 	if err != nil {
 		return nil, fmt.Errorf("error generating machine: %w", err)
 	}
-	_ = ctrl.SetControllerReference(kcp, machine, c.Scheme)
+	_ = ctrl.SetControllerReference(kcp, machine, c.Client.Scheme())
 
 	err = c.Client.Patch(ctx, machine, client.Apply, &client.PatchOptions{
 		FieldManager: "k0smotron",
@@ -226,7 +226,11 @@ func (c *K0sController) generateMachineFromTemplate(ctx context.Context, name st
 		return nil, err
 	}
 
-	_ = ctrl.SetControllerReference(kcp, infraMachineTemplate, c.Scheme)
+	_ = ctrl.SetControllerReference(cluster, infraMachineTemplate, c.Client.Scheme())
+	err = c.Client.Patch(ctx, infraMachineTemplate, client.Merge, &client.PatchOptions{FieldManager: "k0smotron"})
+	if err != nil {
+		return nil, err
+	}
 
 	template, found, err := unstructured.NestedMap(infraMachineTemplate.UnstructuredContent(), "spec", "template")
 	if !found {