Revert "[chore] delete code to set a version and date, as it it not u…

…sed (open-telemetry#10715)"

This reverts commit b53f57d.

cmd/builder/internal/command.go

@@ -123,7 +123,7 @@ configuration is provided, ocb will generate a default Collector.
 
 func initConfig(flags *flag.FlagSet) error {
 	cfg.Logger.Info("OpenTelemetry Collector Builder",
-		zap.String("version", version))
+		zap.String("version", version), zap.String("date", date))
 
 	var provider koanf.Provider
 

cmd/builder/internal/version.go

@@ -12,12 +12,21 @@ import (
 
 var (
 	version = ""
+	date    = "unknown"
 )
 
-func init() {
-	// the second returned value is a boolean, which is true if the binaries are built with module support.
-	info, _ := debug.ReadBuildInfo()
-	version = info.Main.Version
+// binVersion returns the version of the binary.
+// If the version is not set, it attempts to read the build information.
+// Returns an error if the build information cannot be read.
+func binVersion() (string, error) {
+	if version != "" {
+		return version, nil
+	}
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return "", fmt.Errorf("failed to read build info")
+	}
+	return info.Main.Version, nil
 }
 
 func versionCommand() *cobra.Command {
@@ -26,6 +35,10 @@ func versionCommand() *cobra.Command {
 		Short: "Version of ocb",
 		Long:  "Prints the version of the ocb binary",
 		RunE: func(cmd *cobra.Command, _ []string) error {
+			version, err := binVersion()
+			if err != nil {
+				return err
+			}
 			cmd.Println(fmt.Sprintf("%s version %s", cmd.Parent().Name(), version))
 			return nil
 		},