feat: add application versioning support to backend and UI

- Introduce APP_VERSION build argument and environment variable in Dockerfile.
- Load AppVersion from environment variables in the configuration loader.
- Pass the application version to the HTML renderer and expose it to templates via PageData.
- Update tests to verify the version is correctly rendered in the footer.

backend/libs/config/config.go

@@ -12,6 +12,7 @@ import (
 
 type Config struct {
 	AppName          string
+	AppVersion       string
 	Environment      string
 	Addr             string
 	BaseURL          string
@@ -54,6 +55,7 @@ type SettingsDefaults struct {
 func Load() (Config, error) {
 	cfg := Config{
 		AppName:          envString("WARPBOX_APP_NAME", "warpbox.dev"),
+		AppVersion:       envString("APP_VERSION", "dev"),
 		Environment:      envString("WARPBOX_ENV", "development"),
 		Addr:             envString("WARPBOX_ADDR", ":8080"),
 		BaseURL:          strings.TrimRight(envString("WARPBOX_BASE_URL", "http://localhost:8080"), "/"),

backend/libs/handlers/accounts_test.go

@@ -569,6 +569,9 @@ func TestHomeReflectsUploadPolicySettings(t *testing.T) {
 	if !strings.Contains(body, "Max file size: 123 MB") || !strings.Contains(body, "456 MB") {
 		t.Fatalf("home did not reflect policy settings: %s", body)
 	}
+	if !strings.Contains(body, "warpbox.dev · test ·") {
+		t.Fatalf("home footer did not include app version: %s", body)
+	}
 }
 
 func TestAPIDocsHeaderReflectsLoggedInUser(t *testing.T) {

backend/libs/handlers/upload_stage3_test.go

@@ -179,6 +179,7 @@ func newTestApp(t *testing.T) (*App, func()) {
 	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
 	cfg := config.Config{
 		AppName:       "warpbox.dev",
+		AppVersion:    "test",
 		BaseURL:       "http://example.test",
 		DataDir:       filepath.Join(root, "data"),
 		StaticDir:     staticDir,
@@ -197,7 +198,7 @@ func newTestApp(t *testing.T) (*App, func()) {
 	if err != nil {
 		t.Fatalf("NewUploadService returned error: %v", err)
 	}
-	renderer, err := web.NewRenderer(cfg.TemplateDir, cfg.AppName, cfg.BaseURL)
+	renderer, err := web.NewRenderer(cfg.TemplateDir, cfg.AppName, cfg.AppVersion, cfg.BaseURL)
 	if err != nil {
 		service.Close()
 		t.Fatalf("NewRenderer returned error: %v", err)

backend/libs/httpserver/server.go

@@ -13,7 +13,7 @@ import (
 )
 
 func New(cfg config.Config, logger *slog.Logger) (*http.Server, error) {
-	renderer, err := web.NewRenderer(cfg.TemplateDir, cfg.AppName, cfg.BaseURL)
+	renderer, err := web.NewRenderer(cfg.TemplateDir, cfg.AppName, cfg.AppVersion, cfg.BaseURL)
 	if err != nil {
 		return nil, err
 	}

backend/libs/web/renderer.go

@@ -8,13 +8,15 @@ import (
 )
 
 type Renderer struct {
-	templates map[string]*template.Template
-	appName   string
-	baseURL   string
+	templates  map[string]*template.Template
+	appName    string
+	appVersion string
+	baseURL    string
 }
 
 type PageData struct {
 	AppName     string
+	AppVersion  string
 	BaseURL     string
 	Title       string
 	Description string
@@ -25,7 +27,7 @@ type PageData struct {
 	Data        any
 }
 
-func NewRenderer(templateDir, appName, baseURL string) (*Renderer, error) {
+func NewRenderer(templateDir, appName, appVersion, baseURL string) (*Renderer, error) {
 	layouts, err := filepath.Glob(filepath.Join(templateDir, "layouts", "*.html"))
 	if err != nil {
 		return nil, err
@@ -56,14 +58,16 @@ func NewRenderer(templateDir, appName, baseURL string) (*Renderer, error) {
 	}
 
 	return &Renderer{
-		templates: templates,
-		appName:   appName,
-		baseURL:   baseURL,
+		templates:  templates,
+		appName:    appName,
+		appVersion: appVersion,
+		baseURL:    baseURL,
 	}, nil
 }
 
 func (r *Renderer) Render(w http.ResponseWriter, status int, page string, data PageData) {
 	data.AppName = r.appName
+	data.AppVersion = r.appVersion
 	data.BaseURL = r.baseURL
 	data.CurrentYear = time.Now().Year()
 

backend/templates/layouts/base.html

@@ -60,7 +60,7 @@
   </main>
 
   <footer class="site-footer">
-    <span>{{.AppName}} · {{.CurrentYear}} · self-hosted</span>
+    <span>{{.AppName}} · {{.AppVersion}} · {{.CurrentYear}} · self-hosted</span>
     <label class="theme-picker">
       <span>Theme</span>
       <select data-theme-select aria-label="Site theme">