feat: add --version flag to print the driver version

Signed-off-by: Anish Ramasekar <anish.ramasekar@gmail.com>

cmd/secrets-store-csi-driver/main.go

@@ -65,6 +65,7 @@ var (
 	enableProfile           = flag.Bool("enable-pprof", false, "enable pprof profiling")
 	profilePort             = flag.Int("pprof-port", 6065, "port for pprof profiling")
 	maxCallRecvMsgSize      = flag.Int("max-call-recv-msg-size", 1024*1024*4, "maximum size in bytes of gRPC response from plugins")
+	versionInfo             = flag.Bool("version", false, "Print the version and exit")
 
 	// Enable optional healthcheck for provider clients that exist in memory
 	providerHealthCheck         = flag.Bool("provider-health-check", false, "Enable health check for configured providers")
@@ -102,6 +103,10 @@ func mainErr() error {
 		return err
 	}
 
+	if *versionInfo {
+		return version.PrintVersion()
+	}
+
 	if *enableProfile {
 		klog.InfoS("Starting profiling", "port", *profilePort)
 		go func() {

pkg/version/version.go

@@ -16,6 +16,7 @@ limitations under the License.
 package version
 
 import (
+	"encoding/json"
 	"fmt"
 	"runtime"
 )
@@ -33,3 +34,25 @@ var (
 func GetUserAgent(controllerName string) string {
 	return fmt.Sprintf("csi-secrets-store/%s/%s (%s/%s) %s/%s", controllerName, BuildVersion, runtime.GOOS, runtime.GOARCH, Vcs, BuildTime)
 }
+
+// PrintVersion prints the current driver version
+func PrintVersion() error {
+	var err error
+	pv := struct {
+		BuildVersion string
+		GitCommit    string
+		BuildDate    string
+	}{
+		BuildDate:    BuildTime,
+		BuildVersion: BuildVersion,
+		GitCommit:    Vcs,
+	}
+
+	var res []byte
+	if res, err = json.Marshal(pv); err != nil {
+		return err
+	}
+
+	fmt.Printf(string(res) + "\n")
+	return nil
+}

pkg/version/version_test.go

@@ -17,7 +17,10 @@ limitations under the License.
 package version
 
 import (
+	"bytes"
 	"fmt"
+	"io"
+	"os"
 	"runtime"
 	"strings"
 	"testing"
@@ -35,3 +38,36 @@ func TestGetUserAgent(t *testing.T) {
 		t.Fatalf("expected: %s, got: %s", expected, actual)
 	}
 }
+
+func TestPrintVersion(t *testing.T) {
+	BuildTime = "Now"
+	BuildVersion = "version"
+	Vcs = "hash"
+
+	old := os.Stdout // keep backup of the real stdout
+	r, w, _ := os.Pipe()
+	os.Stdout = w
+
+	err := PrintVersion()
+
+	outC := make(chan string)
+	// copy the output in a separate goroutine so printing can't block indefinitely
+	go func() {
+		var buf bytes.Buffer
+		_, _ = io.Copy(&buf, r)
+		outC <- strings.TrimSpace(buf.String())
+	}()
+
+	// back to normal state
+	w.Close()
+	os.Stdout = old // restoring the real stdout
+	out := <-outC
+
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+	expected := `{"BuildVersion":"version","GitCommit":"hash","BuildDate":"Now"}`
+	if !strings.EqualFold(out, expected) {
+		t.Fatalf("PrintVersion() expected %s, got %s", expected, out)
+	}
+}