feat(version): collect build-time metadata for uncloud binaries in version pkg

internal/version/version.go

@@ -1,6 +1,13 @@
 package version
 
-var version string
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+	"text/tabwriter"
+
+	goversion "github.com/caarlos0/go-version"
+)
 
 func String() string {
 	if version == "" {
@@ -8,3 +15,83 @@ func String() string {
 	}
 	return version
 }
+
+// Build-time metadata injected via -ldflags by GoReleaser (see .goreleaser.yaml).
+// These are package-level so the same paths can be referenced from any binary's ldflags.
+var (
+	version string
+	commit  string
+	dirty   string
+	date    string
+	builtBy string
+)
+
+// Info holds version and build metadata for an Uncloud binary.
+type Info struct {
+	Version   string
+	GitCommit string
+	GitState  string
+	BuildDate string
+	BuiltBy   string
+	GoVersion string
+	Platform  string
+}
+
+// String returns the human-readable representation of Info as a tab-aligned key-value block.
+func (i Info) String() string {
+	var b strings.Builder
+	w := tabwriter.NewWriter(&b, 0, 0, 2, ' ', 0)
+	fmt.Fprintf(w, "Version:\t%s\n", i.Version)
+	fmt.Fprintf(w, "Git commit:\t%s\n", i.GitCommit)
+	fmt.Fprintf(w, "Git state:\t%s\n", i.GitState)
+	fmt.Fprintf(w, "Build date:\t%s\n", i.BuildDate)
+	fmt.Fprintf(w, "Built by:\t%s\n", i.BuiltBy)
+	fmt.Fprintf(w, "Go version:\t%s\n", i.GoVersion)
+	fmt.Fprintf(w, "Platform:\t%s\n", i.Platform)
+	_ = w.Flush()
+	return b.String()
+}
+
+// JSONString returns the JSON-encoded representation of Info, indented for human readability.
+func (i Info) JSONString() (string, error) {
+	b, err := json.MarshalIndent(i, "", "  ")
+	if err != nil {
+		return "", fmt.Errorf("marshal info: %w", err)
+	}
+	return string(b), nil
+}
+
+// GetInfo returns version and build metadata for the current binary. Values injected at build time via
+// -ldflags take precedence over the runtime/debug.BuildInfo fields.
+func GetInfo() Info {
+	vi := goversion.GetVersionInfo(
+		func(i *goversion.Info) {
+			i.GitVersion = String()
+			if commit != "" {
+				i.GitCommit = commit
+			}
+			// The ldflag value is the raw goreleaser {{.IsGitDirty}} boolean string ("true"/"false").
+			switch dirty {
+			case "true":
+				i.GitTreeState = "dirty"
+			case "false":
+				i.GitTreeState = "clean"
+			}
+			if date != "" {
+				i.BuildDate = date
+			}
+			if builtBy != "" {
+				i.BuiltBy = builtBy
+			}
+		},
+	)
+	return Info{
+		Version:   vi.GitVersion,
+		GitCommit: vi.GitCommit,
+		GitState:  vi.GitTreeState,
+		BuildDate: vi.BuildDate,
+		BuiltBy:   vi.BuiltBy,
+		GoVersion: vi.GoVersion,
+		Platform:  vi.Platform,
+	}
+}