fix: ignore metadb errors if tag not found (#2301)

pkg/api/routes.go

@@ -514,7 +514,7 @@ func (rh *RouteHandler) GetManifest(response http.ResponseWriter, request *http.
 
 	if rh.c.MetaDB != nil {
 		err := meta.OnGetManifest(name, reference, mediaType, content, rh.c.StoreController, rh.c.MetaDB, rh.c.Log)
-		if err != nil {
+		if err != nil && !errors.Is(err, zerr.ErrImageMetaNotFound) {
 			response.WriteHeader(http.StatusInternalServerError)
 
 			return

pkg/meta/hooks.go

@@ -100,7 +100,7 @@ func OnDeleteManifest(repo, reference, mediaType string, digest godigest.Digest,
 	return nil
 }
 
-// OnDeleteManifest is called when a manifest is downloaded. It increments the download couter on that manifest.
+// OnGetManifest is called when a manifest is downloaded. It increments the download couter on that manifest.
 func OnGetManifest(name, reference, mediaType string, body []byte,
 	storeController storage.StoreController, metaDB mTypes.MetaDB, log log.Logger,
 ) error {