Renderer: add version information (#34964) (#35245)

* Renderer: add version information

* fix alerting test

(cherry picked from commit 5f6c172b5a)

Co-authored-by: Agnès Toulet <35176601+AgnesToulet@users.noreply.github.com>

pkg/services/rendering/rendering.go

@@ -47,6 +47,7 @@ type RenderingService struct {
 	renderCSVAction renderCSVFunc
 	domain          string
 	inProgressCount int
+	version         string
 
 	Cfg                *setting.Cfg             `inject:""`
 	RemoteCacheService *remotecache.RemoteCache `inject:""`
@@ -86,7 +87,14 @@ func (rs *RenderingService) Init() error {
 func (rs *RenderingService) Run(ctx context.Context) error {
 	if rs.remoteAvailable() {
 		rs.log = rs.log.New("renderer", "http")
-		rs.log.Info("Backend rendering via external http server")
+
+		version, err := rs.getRemotePluginVersion()
+		if err != nil {
+			rs.log.Info("Couldn't get remote renderer version", "err", err)
+		}
+
+		rs.log.Info("Backend rendering via external http server", "version", version)
+		rs.version = version
 		rs.renderAction = rs.renderViaHTTP
 		rs.renderCSVAction = rs.renderCSVViaHTTP
 		<-ctx.Done()
@@ -101,6 +109,7 @@ func (rs *RenderingService) Run(ctx context.Context) error {
 			return err
 		}
 
+		rs.version = rs.pluginInfo.Info.Version
 		rs.renderAction = rs.renderViaPlugin
 		rs.renderCSVAction = rs.renderCSVViaPlugin
 		<-ctx.Done()
@@ -127,6 +136,10 @@ func (rs *RenderingService) IsAvailable() bool {
 	return rs.remoteAvailable() || rs.pluginAvailable()
 }
 
+func (rs *RenderingService) Version() string {
+	return rs.version
+}
+
 func (rs *RenderingService) RenderErrorImage(err error) (*RenderResult, error) {
 	imgUrl := "public/img/rendering_error.png"