feat: providing binary version and details

Dockerfile

@@ -2,6 +2,12 @@
 FROM golang:1.18 as builder
 
 ARG TARGETARCH
+ARG GIT_HEAD_COMMIT
+ARG GIT_TAG_COMMIT
+ARG GIT_LAST_TAG
+ARG GIT_MODIFIED
+ARG GIT_REPO
+ARG BUILD_DATE
 
 WORKDIR /workspace
 # Copy the Go Modules manifests
@@ -18,7 +24,9 @@ COPY controllers/ controllers/
 COPY internal/ internal/
 
 # Build
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=$TARGETARCH go build -a -o manager main.go
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=$TARGETARCH go build \
+    -ldflags "-X github.com/clastix/kamaji/internal.GitRepo=$GIT_REPO -X github.com/clastix/kamaji/internal.GitTag=$GIT_LAST_TAG -X github.com/clastix/kamaji/internal.GitCommit=$GIT_HEAD_COMMIT -X github.com/clastix/kamaji/internal.GitDirty=$GIT_MODIFIED -X github.com/clastix/kamaji/internal.BuildTime=$BUILD_DATE" \
+    -a -o manager main.go
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details

Makefile

@@ -106,6 +106,15 @@ test:
 
 ##@ Build
 
+# Get information about git current status
+GIT_HEAD_COMMIT ?= $$(git rev-parse --short HEAD)
+GIT_TAG_COMMIT  ?= $$(git rev-parse --short $(VERSION))
+GIT_MODIFIED_1  ?= $$(git diff $(GIT_HEAD_COMMIT) $(GIT_TAG_COMMIT) --quiet && echo "" || echo ".dev")
+GIT_MODIFIED_2  ?= $$(git diff --quiet && echo "" || echo ".dirty")
+GIT_MODIFIED    ?= $$(echo "$(GIT_MODIFIED_1)$(GIT_MODIFIED_2)")
+GIT_REPO        ?= $$(git config --get remote.origin.url)
+BUILD_DATE      ?= $$(git log -1 --format="%at" | xargs -I{} date -d @{} +%Y-%m-%dT%H:%M:%S)
+
 build: generate fmt vet ## Build manager binary.
 	go build -o bin/manager main.go
 
@@ -113,7 +122,12 @@ run: manifests generate fmt vet ## Run a controller from your host.
 	go run ./main.go
 
 docker-build: ## Build docker image with the manager.
-	docker build -t ${IMG} .
+	docker build -t ${IMG} . --build-arg GIT_HEAD_COMMIT=$(GIT_HEAD_COMMIT) \
+		--build-arg GIT_TAG_COMMIT=$(GIT_TAG_COMMIT) \
+		--build-arg GIT_MODIFIED=$(GIT_MODIFIED) \
+		--build-arg GIT_REPO=$(GIT_REPO) \
+		--build-arg GIT_LAST_TAG=$(VERSION) \
+		--build-arg BUILD_DATE=$(BUILD_DATE)
 
 docker-push: ## Push docker image with the manager.
 	docker push ${IMG}

internal/version.go

@@ -0,0 +1,12 @@
+// Copyright 2022 Clastix Labs
+// SPDX-License-Identifier: Apache-2.0
+
+package internal
+
+var (
+	GitRepo   = ""
+	GitTag    = "dev"
+	GitCommit = ""
+	GitDirty  = "dirty"
+	BuildTime = ""
+)

main.go

@@ -17,8 +17,10 @@ limitations under the License.
 package main
 
 import (
+	"fmt"
 	"log"
 	"os"
+	goRuntime "runtime"
 
 	"k8s.io/apimachinery/pkg/runtime"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
@@ -29,6 +31,7 @@ import (
 
 	kamajiv1alpha1 "github.com/clastix/kamaji/api/v1alpha1"
 	"github.com/clastix/kamaji/controllers"
+	"github.com/clastix/kamaji/internal"
 	"github.com/clastix/kamaji/internal/config"
 )
 
@@ -50,6 +53,12 @@ func main() {
 		log.Fatalf("Error reading configuration.")
 	}
 
+	setupLog.Info(fmt.Sprintf("Kamaji version %s %s%s", internal.GitTag, internal.GitCommit, internal.GitDirty))
+	setupLog.Info(fmt.Sprintf("Build from: %s", internal.GitRepo))
+	setupLog.Info(fmt.Sprintf("Build date: %s", internal.BuildTime))
+	setupLog.Info(fmt.Sprintf("Go Version: %s", goRuntime.Version()))
+	setupLog.Info(fmt.Sprintf("Go OS/Arch: %s/%s", goRuntime.GOOS, goRuntime.GOARCH))
+
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
 		Scheme:                 scheme,
 		MetricsBindAddress:     conf.GetString("metrics-bind-address"),