Add version flag to generator

ref: #118
ref: https://issues.redhat.com/browse/ACM-5803
Signed-off-by: Dale Haiducek <[email protected]>

Author: dhaiducek

.github/workflows/release.yml

@@ -22,6 +22,11 @@ jobs:
 
       - name: Build project
         run: |
+          GENERATOR_VERSION="$(cat VERSION.txt)"
+          if [[ "${{ github.ref_name }}" != "${GENERATOR_VERSION}" ]]; then
+            echo "ERROR: Tag ${{ github.ref_name }} does not match ${GENERATOR_VERSION} specified in VERSION.txt."
+            exit 1
+          fi
           make build-release
 
       - name: Release

cmd/PolicyGenerator/VERSION.txt

@@ -0,0 +1 @@
+v1.12.2

cmd/PolicyGenerator/main.go

@@ -2,20 +2,48 @@ package main
 
 import (
 	"bytes"
+	_ "embed"
 	"fmt"
 	"os"
+	runtimeDebug "runtime/debug"
 
 	"github.com/spf13/pflag"
 	"open-cluster-management.io/policy-generator-plugin/internal"
 )
 
+//go:embed VERSION.txt
+var version []byte
 var debug = false
 
+// Gather the Git commit
+var gitCommit = func() string {
+	if info, ok := runtimeDebug.ReadBuildInfo(); ok {
+		for _, setting := range info.Settings {
+			if setting.Key == "vcs.revision" {
+				return setting.Value
+			}
+		}
+	}
+
+	return ""
+}()
+
 func main() {
 	// Parse command input
 	debugFlag := pflag.Bool("debug", false, "Print the stack trace with error messages")
+	versionFlag := pflag.Bool("version", false, "Print the version of the generator")
 	pflag.Parse()
 
+	if *versionFlag {
+		versionStr := string(version)
+		if gitCommit != "" {
+			versionStr = fmt.Sprintf("%s-%s", versionStr, gitCommit)
+		}
+		//nolint:forbidigo
+		fmt.Println(versionStr)
+		os.Exit(0)
+	}
+
 	debug = *debugFlag
 
 	// Collect and parse PolicyGeneratorConfig file paths