Add gitea manager reload-templates command (#24843)

This can be useful to update custom templates in production mode, when
they are updated frequently and a full Gitea restart each time is
disruptive.

modules/private/manager.go

@@ -29,6 +29,13 @@ func Restart(ctx context.Context) ResponseExtra {
 	return requestJSONClientMsg(req, "Restarting")
 }
 
+// ReloadTemplates calls the internal reload-templates function
+func ReloadTemplates(ctx context.Context) ResponseExtra {
+	reqURL := setting.LocalURL + "api/internal/manager/reload-templates"
+	req := newInternalRequest(ctx, reqURL, "POST")
+	return requestJSONClientMsg(req, "Reloaded")
+}
+
 // FlushOptions represents the options for the flush call
 type FlushOptions struct {
 	Timeout     time.Duration

modules/templates/htmlrenderer.go

@@ -96,6 +96,14 @@ func HTMLRenderer() *HTMLRender {
 	return htmlRender
 }
 
+func ReloadHTMLTemplates() error {
+	if err := htmlRender.CompileTemplates(); err != nil {
+		log.Error("Template error: %v\n%s", err, log.Stack(2))
+		return err
+	}
+	return nil
+}
+
 func initHTMLRenderer() {
 	rendererType := "static"
 	if !setting.IsProd {
@@ -115,9 +123,7 @@ func initHTMLRenderer() {
 
 	if !setting.IsProd {
 		go AssetFS().WatchLocalChanges(graceful.GetManager().ShutdownContext(), func() {
-			if err := htmlRender.CompileTemplates(); err != nil {
-				log.Error("Template error: %v\n%s", err, log.Stack(2))
-			}
+			_ = ReloadHTMLTemplates()
 		})
 	}
 }