initial commit

.dockerignore

@@ -0,0 +1,3 @@
+# More info: https://docs.docker.com/engine/reference/builder/#dockerignore-file
+# Ignore build and test binaries.
+bin/

.gitignore

@@ -0,0 +1,28 @@
+
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+bin/*
+Dockerfile.cross
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Go workspace file
+go.work
+
+# Kubernetes Generated files - skip generated files, except for vendored files
+!vendor/**/zz_generated.*
+
+# editor and IDE paraphernalia
+.idea
+.vscode
+*.swp
+*.swo
+*~

.golangci.yml

@@ -0,0 +1,40 @@
+run:
+  deadline: 5m
+  allow-parallel-runners: true
+
+issues:
+  # don't skip warning about doc comments
+  # don't exclude the default set of lint
+  exclude-use-default: false
+  # restore some of the defaults
+  # (fill in the rest as needed)
+  exclude-rules:
+    - path: "api/*"
+      linters:
+        - lll
+    - path: "internal/*"
+      linters:
+        - dupl
+        - lll
+linters:
+  disable-all: true
+  enable:
+    - dupl
+    - errcheck
+    - exportloopref
+    - goconst
+    - gocyclo
+    - gofmt
+    - goimports
+    - gosimple
+    - govet
+    - ineffassign
+    - lll
+    - misspell
+    - nakedret
+    - prealloc
+    - staticcheck
+    - typecheck
+    - unconvert
+    - unparam
+    - unused

Dockerfile

@@ -0,0 +1,33 @@
+# Build the manager binary
+FROM golang:1.21 AS builder
+ARG TARGETOS
+ARG TARGETARCH
+
+WORKDIR /workspace
+# Copy the Go Modules manifests
+COPY go.mod go.mod
+COPY go.sum go.sum
+# cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN go mod download
+
+# Copy the go source
+COPY cmd/main.go cmd/main.go
+COPY api/ api/
+COPY internal/controller/ internal/controller/
+
+# Build
+# the GOARCH has not a default value to allow the binary be built according to the host where the command
+# was called. For example, if we call make docker-build in a local env which has the Apple Silicon M1 SO
+# the docker BUILDPLATFORM arg will be linux/arm64 when for Apple x86 it will be linux/amd64. Therefore,
+# by leaving it empty we can ensure that the container and binary shipped on it will have the same platform.
+RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -a -o manager cmd/main.go
+
+# Use distroless as minimal base image to package the manager binary
+# Refer to https://github.com/GoogleContainerTools/distroless for more details
+FROM gcr.io/distroless/static:nonroot
+WORKDIR /
+COPY --from=builder /workspace/manager .
+USER 65532:65532
+
+ENTRYPOINT ["/manager"]

Makefile

@@ -0,0 +1,203 @@
+
+# Image URL to use all building/pushing image targets
+IMG ?= controller:latest
+# ENVTEST_K8S_VERSION refers to the version of kubebuilder assets to be downloaded by envtest binary.
+ENVTEST_K8S_VERSION = 1.29.0
+
+# Get the currently used golang install path (in GOPATH/bin, unless GOBIN is set)
+ifeq (,$(shell go env GOBIN))
+GOBIN=$(shell go env GOPATH)/bin
+else
+GOBIN=$(shell go env GOBIN)
+endif
+
+# CONTAINER_TOOL defines the container tool to be used for building images.
+# Be aware that the target commands are only tested with Docker which is
+# scaffolded by default. However, you might want to replace it to use other
+# tools. (i.e. podman)
+CONTAINER_TOOL ?= docker
+
+# Setting SHELL to bash allows bash commands to be executed by recipes.
+# Options are set to exit when a recipe line exits non-zero or a piped command fails.
+SHELL = /usr/bin/env bash -o pipefail
+.SHELLFLAGS = -ec
+
+.PHONY: all
+all: build
+
+##@ General
+
+# The help target prints out all targets with their descriptions organized
+# beneath their categories. The categories are represented by '##@' and the
+# target descriptions by '##'. The awk command is responsible for reading the
+# entire set of makefiles included in this invocation, looking for lines of the
+# file as xyz: ## something, and then pretty-format the target and help. Then,
+# if there's a line with ##@ something, that gets pretty-printed as a category.
+# More info on the usage of ANSI control characters for terminal formatting:
+# https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_parameters
+# More info on the awk command:
+# http://linuxcommand.org/lc3_adv_awk.php
+
+.PHONY: help
+help: ## Display this help.
+	@awk 'BEGIN {FS = ":.*##"; printf "\nUsage:\n  make \033[36m<target>\033[0m\n"} /^[a-zA-Z_0-9-]+:.*?##/ { printf "  \033[36m%-15s\033[0m %s\n", $$1, $$2 } /^##@/ { printf "\n\033[1m%s\033[0m\n", substr($$0, 5) } ' $(MAKEFILE_LIST)
+
+##@ Development
+
+.PHONY: manifests
+manifests: controller-gen ## Generate WebhookConfiguration, ClusterRole and CustomResourceDefinition objects.
+	$(CONTROLLER_GEN) rbac:roleName=manager-role crd webhook paths="./..." output:crd:artifacts:config=config/crd/bases
+
+.PHONY: generate
+generate: controller-gen ## Generate code containing DeepCopy, DeepCopyInto, and DeepCopyObject method implementations.
+	$(CONTROLLER_GEN) object:headerFile="hack/boilerplate.go.txt" paths="./..."
+
+.PHONY: fmt
+fmt: ## Run go fmt against code.
+	go fmt ./...
+
+.PHONY: vet
+vet: ## Run go vet against code.
+	go vet ./...
+
+.PHONY: test
+test: manifests generate fmt vet envtest ## Run tests.
+	KUBEBUILDER_ASSETS="$(shell $(ENVTEST) use $(ENVTEST_K8S_VERSION) --bin-dir $(LOCALBIN) -p path)" go test $$(go list ./... | grep -v /e2e) -coverprofile cover.out
+
+# Utilize Kind or modify the e2e tests to load the image locally, enabling compatibility with other vendors.
+.PHONY: test-e2e  # Run the e2e tests against a Kind k8s instance that is spun up.
+test-e2e:
+	go test ./test/e2e/ -v -ginkgo.v
+
+.PHONY: lint
+lint: golangci-lint ## Run golangci-lint linter & yamllint
+	$(GOLANGCI_LINT) run
+
+.PHONY: lint-fix
+lint-fix: golangci-lint ## Run golangci-lint linter and perform fixes
+	$(GOLANGCI_LINT) run --fix
+
+##@ Build
+
+.PHONY: build
+build: manifests generate fmt vet ## Build manager binary.
+	go build -o bin/manager cmd/main.go
+
+.PHONY: run
+run: manifests generate fmt vet ## Run a controller from your host.
+	go run ./cmd/main.go
+
+# If you wish to build the manager image targeting other platforms you can use the --platform flag.
+# (i.e. docker build --platform linux/arm64). However, you must enable docker buildKit for it.
+# More info: https://docs.docker.com/develop/develop-images/build_enhancements/
+.PHONY: docker-build
+docker-build: ## Build docker image with the manager.
+	$(CONTAINER_TOOL) build -t ${IMG} .
+
+.PHONY: docker-push
+docker-push: ## Push docker image with the manager.
+	$(CONTAINER_TOOL) push ${IMG}
+
+# PLATFORMS defines the target platforms for the manager image be built to provide support to multiple
+# architectures. (i.e. make docker-buildx IMG=myregistry/mypoperator:0.0.1). To use this option you need to:
+# - be able to use docker buildx. More info: https://docs.docker.com/build/buildx/
+# - have enabled BuildKit. More info: https://docs.docker.com/develop/develop-images/build_enhancements/
+# - be able to push the image to your registry (i.e. if you do not set a valid value via IMG=<myregistry/image:<tag>> then the export will fail)
+# To adequately provide solutions that are compatible with multiple platforms, you should consider using this option.
+PLATFORMS ?= linux/arm64,linux/amd64,linux/s390x,linux/ppc64le
+.PHONY: docker-buildx
+docker-buildx: ## Build and push docker image for the manager for cross-platform support
+	# copy existing Dockerfile and insert --platform=${BUILDPLATFORM} into Dockerfile.cross, and preserve the original Dockerfile
+	sed -e '1 s/\(^FROM\)/FROM --platform=\$$\{BUILDPLATFORM\}/; t' -e ' 1,// s//FROM --platform=\$$\{BUILDPLATFORM\}/' Dockerfile > Dockerfile.cross
+	- $(CONTAINER_TOOL) buildx create --name project-v3-builder
+	$(CONTAINER_TOOL) buildx use project-v3-builder
+	- $(CONTAINER_TOOL) buildx build --push --platform=$(PLATFORMS) --tag ${IMG} -f Dockerfile.cross .
+	- $(CONTAINER_TOOL) buildx rm project-v3-builder
+	rm Dockerfile.cross
+
+.PHONY: build-installer
+build-installer: manifests generate kustomize ## Generate a consolidated YAML with CRDs and deployment.
+	mkdir -p dist
+	@if [ -d "config/crd" ]; then \
+		$(KUSTOMIZE) build config/crd > dist/install.yaml; \
+	fi
+	echo "---" >> dist/install.yaml  # Add a document separator before appending
+	cd config/manager && $(KUSTOMIZE) edit set image controller=${IMG}
+	$(KUSTOMIZE) build config/default >> dist/install.yaml
+
+##@ Deployment
+
+ifndef ignore-not-found
+  ignore-not-found = false
+endif
+
+.PHONY: install
+install: manifests kustomize ## Install CRDs into the K8s cluster specified in ~/.kube/config.
+	$(KUSTOMIZE) build config/crd | $(KUBECTL) apply -f -
+
+.PHONY: uninstall
+uninstall: manifests kustomize ## Uninstall CRDs from the K8s cluster specified in ~/.kube/config. Call with ignore-not-found=true to ignore resource not found errors during deletion.
+	$(KUSTOMIZE) build config/crd | $(KUBECTL) delete --ignore-not-found=$(ignore-not-found) -f -
+
+.PHONY: deploy
+deploy: manifests kustomize ## Deploy controller to the K8s cluster specified in ~/.kube/config.
+	cd config/manager && $(KUSTOMIZE) edit set image controller=${IMG}
+	$(KUSTOMIZE) build config/default | $(KUBECTL) apply -f -
+
+.PHONY: undeploy
+undeploy: kustomize ## Undeploy controller from the K8s cluster specified in ~/.kube/config. Call with ignore-not-found=true to ignore resource not found errors during deletion.
+	$(KUSTOMIZE) build config/default | $(KUBECTL) delete --ignore-not-found=$(ignore-not-found) -f -
+
+##@ Dependencies
+
+## Location to install dependencies to
+LOCALBIN ?= $(shell pwd)/bin
+$(LOCALBIN):
+	mkdir -p $(LOCALBIN)
+
+## Tool Binaries
+KUBECTL ?= kubectl
+KUSTOMIZE ?= $(LOCALBIN)/kustomize-$(KUSTOMIZE_VERSION)
+CONTROLLER_GEN ?= $(LOCALBIN)/controller-gen-$(CONTROLLER_TOOLS_VERSION)
+ENVTEST ?= $(LOCALBIN)/setup-envtest-$(ENVTEST_VERSION)
+GOLANGCI_LINT = $(LOCALBIN)/golangci-lint-$(GOLANGCI_LINT_VERSION)
+
+## Tool Versions
+KUSTOMIZE_VERSION ?= v5.3.0
+CONTROLLER_TOOLS_VERSION ?= v0.14.0
+ENVTEST_VERSION ?= latest
+GOLANGCI_LINT_VERSION ?= v1.54.2
+
+.PHONY: kustomize
+kustomize: $(KUSTOMIZE) ## Download kustomize locally if necessary.
+$(KUSTOMIZE): $(LOCALBIN)
+	$(call go-install-tool,$(KUSTOMIZE),sigs.k8s.io/kustomize/kustomize/v5,$(KUSTOMIZE_VERSION))
+
+.PHONY: controller-gen
+controller-gen: $(CONTROLLER_GEN) ## Download controller-gen locally if necessary.
+$(CONTROLLER_GEN): $(LOCALBIN)
+	$(call go-install-tool,$(CONTROLLER_GEN),sigs.k8s.io/controller-tools/cmd/controller-gen,$(CONTROLLER_TOOLS_VERSION))
+
+.PHONY: envtest
+envtest: $(ENVTEST) ## Download setup-envtest locally if necessary.
+$(ENVTEST): $(LOCALBIN)
+	$(call go-install-tool,$(ENVTEST),sigs.k8s.io/controller-runtime/tools/setup-envtest,$(ENVTEST_VERSION))
+
+.PHONY: golangci-lint
+golangci-lint: $(GOLANGCI_LINT) ## Download golangci-lint locally if necessary.
+$(GOLANGCI_LINT): $(LOCALBIN)
+	$(call go-install-tool,$(GOLANGCI_LINT),github.com/golangci/golangci-lint/cmd/golangci-lint,${GOLANGCI_LINT_VERSION})
+
+# go-install-tool will 'go install' any package with custom target and name of binary, if it doesn't exist
+# $1 - target path with name of binary (ideally with version)
+# $2 - package url which can be installed
+# $3 - specific version of package
+define go-install-tool
+@[ -f $(1) ] || { \
+set -e; \
+package=$(2)@$(3) ;\
+echo "Downloading $${package}" ;\
+GOBIN=$(LOCALBIN) go install $${package} ;\
+mv "$$(echo "$(1)" | sed "s/-$(3)$$//")" $(1) ;\
+}
+endef

PROJECT

@@ -0,0 +1,20 @@
+# Code generated by tool. DO NOT EDIT.
+# This file is used to track the info used to scaffold your project
+# and allow the plugins properly work.
+# More info: https://book.kubebuilder.io/reference/project-config.html
+domain: example.com
+layout:
+- go.kubebuilder.io/v4
+projectName: operator-tutorial
+repo: github.com/aghilish/operator-tutorial
+resources:
+- api:
+    crdVersion: v1
+    namespaced: true
+  controller: true
+  domain: example.com
+  group: blog
+  kind: Ghost
+  path: github.com/aghilish/operator-tutorial/api/v1
+  version: v1
+version: "3"

api/v1/ghost_types.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2024.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package v1
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// EDIT THIS FILE!  THIS IS SCAFFOLDING FOR YOU TO OWN!
+// NOTE: json tags are required.  Any new fields you add must have json tags for the fields to be serialized.
+
+// GhostSpec defines the desired state of Ghost
+type GhostSpec struct {
+	//+kubebuilder:validation:Pattern=`^[-a-z0-9]*$`
+	ImageTag string `json:"imageTag"`
+}
+
+// GhostStatus defines the observed state of Ghost
+type GhostStatus struct {
+	Conditions []metav1.Condition `json:"conditions,omitempty"`
+}
+
+//+kubebuilder:object:root=true
+//+kubebuilder:subresource:status
+
+// Ghost is the Schema for the ghosts API
+type Ghost struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata,omitempty"`
+
+	Spec   GhostSpec   `json:"spec,omitempty"`
+	Status GhostStatus `json:"status,omitempty"`
+}
+
+//+kubebuilder:object:root=true
+
+// GhostList contains a list of Ghost
+type GhostList struct {
+	metav1.TypeMeta `json:",inline"`
+	metav1.ListMeta `json:"metadata,omitempty"`
+	Items           []Ghost `json:"items"`
+}
+
+func init() {
+	SchemeBuilder.Register(&Ghost{}, &GhostList{})
+}