add buildinfo package to hold ldflags info

internal/buildinfo/buildinfo.go

@@ -0,0 +1,40 @@
+package buildinfo
+
+import (
+	"fmt"
+	"time"
+)
+
+// VersionInfo describes structure of version information objects.
+type VersionInfo struct {
+	Version string
+	Commit  string
+	Date    string
+}
+
+var (
+	version = "development"
+	commit  = "na"
+	date    = time.Now().Local().Format(time.ANSIC)
+
+	// Version provides access to version info and related printing functions.
+	Version *VersionInfo
+)
+
+func init() {
+	Version = &VersionInfo{
+		Version: version,
+		Commit:  commit,
+		Date:    date,
+	}
+}
+
+// Print prints the version information.
+func (v *VersionInfo) Print() {
+	fmt.Printf("Dockma CLI version %s\n", v.Version)
+}
+
+// PrintFull prints the full version information including built date and last commit.
+func (v *VersionInfo) PrintFull() {
+	fmt.Printf("Dockma CLI Version %s built on %s (commit: %s)\n", v.Version, v.Date, v.Commit)
+}