Move to setting version info explicitly in linker flags

We don't have go built-in VCS information in a nix build because the git
repository isn't present. After struggling to build an overlay that
would provide it, I decided this path is easier of just injecting in the
data that we need.

Issue: #5

api/api.go

@@ -322,7 +322,7 @@ type tegolaURLs struct {
 }
 
 func getRoot(ctx context.Context, r *http.Request, q resource.QueryParams) (*about, *nhttp.ErrorWithStatus) {
-	v := version.Get()
+	v := GetVersionInfo()
 	return &about{
 		Environment: config.Environment,
 		SentryDSN:   config.SentryDSNFrontend,

api/event.go

@@ -11,7 +11,6 @@ import (
 	"source.gleipnir.technology/Gleipnir/nidus-sync/lint"
 	"source.gleipnir.technology/Gleipnir/nidus-sync/platform"
 	"source.gleipnir.technology/Gleipnir/nidus-sync/platform/event"
-	"source.gleipnir.technology/Gleipnir/nidus-sync/version"
 )
 
 var connectionsSSE map[*ConnectionSSE]bool = make(map[*ConnectionSSE]bool, 0)
@@ -41,7 +40,7 @@ type Status struct {
 
 func (c *ConnectionSSE) SendEvent(w http.ResponseWriter, m platform.Event) error {
 	if m.Type == event.EventTypeShutdown {
-		v := version.Get()
+		v := GetVersionInfo()
 		return send(w, Status{
 			BuildTime:  v.BuildTime,
 			IsModified: v.IsModified,
@@ -121,7 +120,7 @@ func streamEvents(w http.ResponseWriter, r *http.Request, u platform.User) {
 	log.Debug().Int32("org", u.Organization.ID).Int("user", u.ID).Str("id", uid.String()).Msg("connected SSE client")
 
 	// Send an initial connected event
-	v := version.Get()
+	v := GetVersionInfo()
 	status := Status{
 		BuildTime:  v.BuildTime,
 		IsModified: v.IsModified,

api/version.go

@@ -0,0 +1,16 @@
+package api
+
+import (
+	"source.gleipnir.technology/Gleipnir/nidus-sync/version"
+)
+
+var (
+	versionInfo version.VersionInfo
+)
+
+func GetVersionInfo() version.VersionInfo {
+	return versionInfo
+}
+func SetVersionInfo(v version.VersionInfo) {
+	versionInfo = v
+}

default.nix

@@ -1,4 +1,4 @@
-{ pkgs ? import <nixpkgs> { }, proj ? pkgs.proj }:
+{ ldflags, version, pkgs ? import <nixpkgs> { }, proj ? pkgs.proj }:
 
 let
   # Get commit timestamp at eval time (pure)
@@ -12,24 +12,12 @@ let
     else "0";
 in
 pkgs.buildGoModule rec {
+  inherit ldflags version;
   pname = "nidus-sync";
-  version = "0.0.12";
   src = ./.;
   
-  gitRevision = 
-    if builtins.pathExists ./.git 
-    then pkgs.lib.commitIdFromGitRepo ./.git 
-    else "unknown";
-  
   buildTime = getCommitTime;
   
-  ldflags = [
-    "-s"
-    "-w"
-    "-X main.Version=${version}"
-    "-X main.Commit=${gitRevision}"
-    "-X main.BuildTime=${buildTime}"
-  ];
   meta = {
     description = "Nidus Sync";
     homepage = "https://github.com/Gleipnir-Technology/nidus-sync";
@@ -74,4 +62,5 @@ pkgs.buildGoModule rec {
     cp -r vite/rmo/static/gen/rmo $out/share/frontend/
     cp -r vite/rmo/static/gen/sync $out/share/frontend/
   '';
+
 }

flake.lock

@@ -75,11 +75,11 @@
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1772542754,
-        "narHash": "sha256-WGV2hy+VIeQsYXpsLjdr4GvHv5eECMISX1zKLTedhdg=",
+        "lastModified": 1778869304,
+        "narHash": "sha256-30sZNZoA1cqF5JNO9fVX+wgiQYjB7HJqqJ4ztCDeBZE=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "8c809a146a140c5c8806f13399592dbcb1bb5dc4",
+        "rev": "d233902339c02a9c334e7e593de68855ad26c4cb",
         "type": "github"
       },
       "original": {

flake.nix

@@ -21,8 +21,32 @@
 				projPkg = proj.packages.${system}.default;
 
 				package = pkgs.callPackage ./default.nix {
-				proj = projPkg;
-			};
+					ldflags = ldflags;
+					proj = projPkg;
+					version = packageVersion;
+				};
+				# Pull VCS metadata from the flake's own git source.
+				# These fields are available when the flake lives inside a git checkout.
+				gitRevision = self.sourceInfo.rev or "dirty";
+				gitShortRev = self.sourceInfo.shortRev or "dirty";
+				gitDateTime = self.sourceInfo.lastModifiedDate or "unknown";
+
+				# Derive a human-readable version from the git date + short rev.
+				# lastModifiedDate is YYYYMMDDHHMMSS; pull out just YYYY-MM-DD.
+				packageVersion =
+				let
+				y  = builtins.substring 0 4 gitDateTime;
+				m  = builtins.substring 4 2 gitDateTime;
+				d  = builtins.substring 6 2 gitDateTime;
+				in "${y}-${m}-${d}.${gitShortRev}";
+
+				ldflags = [
+				"-s" "-w"
+				"-X main.BuildTime=${gitDateTime}"
+				"-X main.Revision=${gitRevision}"
+				"-X main.Version=${packageVersion}"
+       				];
+
 			in
 			{
 				packages.default = package;

main.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"os/signal"
 	"runtime/debug"
+	//"strconv"
 	"syscall"
 	"time"
 
@@ -33,6 +34,13 @@ import (
 	"source.gleipnir.technology/Gleipnir/nidus-sync/version"
 )
 
+// These will be set by ldflags at build time by Nix
+var (
+	BuildTime = "unknown"
+	Revision  = "unknown"
+	Version   = "dev"
+)
+
 func main() {
 	err := config.Parse()
 	if err != nil {
@@ -46,8 +54,19 @@ func main() {
 		log.Warn().Msg("Forcing production mode for testing templates")
 		config.Environment = "PRODUCTION"
 	}
-	v := version.Get()
-	log.Info().Str("environment", config.Environment).Bool("is-prod", config.IsProductionEnvironment()).Str("revision", v.Revision).Str("build_time", v.BuildTime.String()).Bool("is modified", v.IsModified).Msg("Starting")
+	v := GetVersionInfo()
+	log.Info().
+		Str("environment", config.Environment).
+		Bool("is-prod", config.IsProductionEnvironment()).
+		Str("revision", v.Revision).
+		Str("build_time", v.BuildTime.String()).
+		Bool("is modified", v.IsModified).
+		Str("Version", Version).
+		Str("Revision", Revision).
+		Str("BuildDate", BuildTime).
+		Msg("Starting")
+	api.SetVersionInfo(v)
+
 	err = sentry.Init(sentry.ClientOptions{
 		Debug:            false, //!config.IsProductionEnvironment(),
 		Dsn:              config.SentryDSN,
@@ -285,3 +304,50 @@ func LoggerMiddleware(logger *zerolog.Logger) func(next http.Handler) http.Handl
 		return http.HandlerFunc(fn)
 	}
 }
+func GetVersionInfo() (version.VersionInfo, error) {
+	// Try ldflags first (set by Nix build)
+	if Revision != "" && Revision != "unknown" {
+		build_time, err := parseNixTime(BuildTime)
+		if err != nil {
+			return version.VersionInfo{}, fmt.Errorf("parse nix time: %w", err)
+		}
+		return version.VersionInfo{
+			BuildTime:  build_time,
+			IsModified: Revision == "dirty",
+			Revision:   Revision,
+		}, nil
+	}
+
+	// Fallback to debug.ReadBuildInfo() for development
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return version.VersionInfo{}, fmt.Errorf("read build info not ok")
+	}
+
+	var v version.VersionInfo
+	for _, setting := range info.Settings {
+		switch setting.Key {
+		case "vcs.modified":
+			v.IsModified = setting.Value == "true"
+		case "vcs.revision":
+			if len(setting.Value) > 7 {
+				v.Revision = setting.Value[:7]
+			} else {
+				v.Revision = setting.Value
+			}
+		case "vcs.time":
+			if t, err := time.Parse(time.RFC3339, setting.Value); err == nil {
+				v.BuildTime = t
+			}
+		}
+	}
+	return v, nil
+}
+func parseNixTime(timestamp string) (time.Time, error) {
+	layout := "20060102150405"
+	t, err := time.Parse(layout, timestamp)
+	if err != nil {
+		return time.Time{}, err
+	}
+	return t, nil
+}

version/version.go

@@ -1,65 +1,11 @@
 package version
 
 import (
-	"runtime/debug"
-	"strconv"
 	"time"
 )
 
-// These will be set by ldflags at build time
-var (
-	Version    = "dev"
-	Commit     = ""
-	BuildTime  = "0"
-	IsModified = "false"
-)
-
 type VersionInfo struct {
 	BuildTime  time.Time `json:"build_time"`
 	IsModified bool      `json:"is_modified"`
 	Revision   string    `json:"revision"`
 }
-
-func Get() VersionInfo {
-	// Try ldflags first (set by Nix build)
-	if Commit != "" && Commit != "unknown" {
-		var buildTime time.Time
-		if timestamp, err := strconv.ParseInt(BuildTime, 10, 64); err == nil && timestamp > 0 {
-			buildTime = time.Unix(timestamp, 0)
-		}
-
-		return VersionInfo{
-			Revision:   Commit,
-			BuildTime:  buildTime,
-			IsModified: IsModified == "true",
-		}
-	}
-
-	// Fallback to debug.ReadBuildInfo() for development
-	info, ok := debug.ReadBuildInfo()
-	if !ok {
-		return VersionInfo{
-			Revision: "unknown",
-		}
-	}
-
-	var version VersionInfo
-	for _, setting := range info.Settings {
-		switch setting.Key {
-		case "vcs.modified":
-			version.IsModified = setting.Value == "true"
-		case "vcs.revision":
-			if len(setting.Value) > 7 {
-				version.Revision = setting.Value[:7]
-			} else {
-				version.Revision = setting.Value
-			}
-		case "vcs.time":
-			if t, err := time.Parse(time.RFC3339, setting.Value); err == nil {
-				version.BuildTime = t
-			}
-		}
-	}
-
-	return version
-}