Kubernetes Operator - Golang

brew install operator-sdk

operator-sdk version

operator-sdk version: "v1.0.0", commit: "d7d5e0cd6cf5468bb66e0849f08fda5bf557f4fa", kubernetes version: "v1.18.2", go version: "go1.14.7 darwin/amd64", GOOS: "darwin", GOARCH: "amd64"

$ mkdir ~/k8s-operator && cd ~/k8s-operator/

$ operator-sdk init --project-version="2" --repo github.com/imjoseangel/k8s-operator --owner "imjoseangel" --domain example.com

$ operator-sdk create api --kind Presentation --group presentation --version v2

This command specifies that the CRD will be called Presentation and creates the file api/v1/presentation_types.go, which you can modify to specify the input parameter of your CRD. For this example application, you need only one parameter, called Markdown:

// PresentationSpec defines the desired state of Presentation
type PresentationSpec struct {
	// INSERT ADDITIONAL SPEC FIELDS - desired state of cluster
	// Important: Run "make" to regenerate code after modifying this file

	// Foo is an example field of Presentation. Edit Presentation_types.go to remove/update
	Markdown string `json:"markdown,omitempty"`
}

After modifying the *_types.go file always run the following command to update the generated code for that resource type

$ make generate

Once the API is defined with spec/status fields and CRD validation markers, the CRD manifests can be generated and updated with the following command:

$ make manifests

This makefile target will invoke controller-gen to generate the CRD manifests at config/crd/bases/presentation.example.com_presentations.yaml.

Setup the envtest binaries and environment for your project. Update your test Makefile target to the following:

# Run tests
ENVTEST_ASSETS_DIR=$(shell pwd)/testbin
test: generate fmt vet manifests
	mkdir -p ${ENVTEST_ASSETS_DIR}
	test -f ${ENVTEST_ASSETS_DIR}/setup-envtest.sh || curl -sSLo ${ENVTEST_ASSETS_DIR}/setup-envtest.sh https://raw.githubusercontent.com/kubernetes-sigs/controller-runtime/master/hack/setup-envtest.sh
	source ${ENVTEST_ASSETS_DIR}/setup-envtest.sh; fetch_envtest_tools $(ENVTEST