use go's own git version info

main.go

@@ -6,18 +6,23 @@ import (
 	"log"
 	"os"
 	"runtime"
+	"runtime/debug"
 
 	"github.com/docker/docker/client"
 	"github.com/go-errors/errors"
 	"github.com/integrii/flaggy"
 	"github.com/jesseduffield/lazydocker/pkg/app"
 	"github.com/jesseduffield/lazydocker/pkg/config"
+	"github.com/jesseduffield/lazydocker/pkg/utils"
 	"github.com/jesseduffield/yaml"
+	"github.com/samber/lo"
 )
 
+const DEFAULT_VERSION = "unversioned"
+
 var (
 	commit      string
-	version     = "unversioned"
+	version     = DEFAULT_VERSION
 	date        string
 	buildSource = "unknown"
 
@@ -27,6 +32,8 @@ var (
 )
 
 func main() {
+	updateBuildInfo()
+
 	info := fmt.Sprintf(
 		"%s\nDate: %s\nBuildSource: %s\nCommit: %s\nOS: %s\nArch: %s",
 		version,
@@ -93,3 +100,27 @@ func main() {
 		log.Fatal(fmt.Sprintf("%s\n\n%s", app.Tr.ErrorOccurred, stackTrace))
 	}
 }
+
+func updateBuildInfo() {
+	if version == DEFAULT_VERSION {
+		if buildInfo, ok := debug.ReadBuildInfo(); ok {
+			revision, ok := lo.Find(buildInfo.Settings, func(setting debug.BuildSetting) bool {
+				return setting.Key == "vcs.revision"
+			})
+			if ok {
+				commit = revision.Value
+				// if lazydocker was built from source we'll show the version as the
+				// abbreviated commit hash
+				version = utils.SafeTruncate(revision.Value, 7)
+			}
+
+			// if version hasn't been set we assume that neither has the date
+			time, ok := lo.Find(buildInfo.Settings, func(setting debug.BuildSetting) bool {
+				return setting.Key == "vcs.time"
+			})
+			if ok {
+				date = time.Value
+			}
+		}
+	}
+}

pkg/gui/layout.go

@@ -62,7 +62,7 @@ func (gui *Gui) layout(g *gocui.Gui) error {
 	g.Highlight = true
 	width, height := g.Size()
 
-	information := "lazydocker " + gui.Config.Version
+	information := gui.Config.Version
 	if gui.g.Mouse {
 		donate := color.New(color.FgMagenta, color.Underline).Sprint(gui.Tr.Donate)
 		information = donate + " " + information

pkg/utils/utils.go

@@ -379,3 +379,11 @@ func CloseMany(closers []io.Closer) error {
 	}
 	return nil
 }
+
+func SafeTruncate(str string, limit int) string {
+	if len(str) > limit {
+		return str[0:limit]
+	} else {
+		return str
+	}
+}