[v9.5.x] Annotations: Ignore unique constraint violations for tags (#66757)

(cherry picked from commit 948131aac3)

Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>

pkg/services/tag/tagimpl/xorm_store.go

@@ -14,16 +14,18 @@ type sqlStore struct {
 func (s *sqlStore) EnsureTagsExist(ctx context.Context, tags []*tag.Tag) ([]*tag.Tag, error) {
 	err := s.db.WithDbSession(ctx, func(sess *db.Session) error {
 		for _, tagElement := range tags {
-			var existingTag tag.Tag
-			exists, err := sess.Table("tag").Where("`key`=? AND `value`=?", tagElement.Key, tagElement.Value).Get(&existingTag)
+			exists, err := s.innerGetTag(sess, tagElement)
 			if err != nil {
 				return err
 			}
-			if exists {
-				tagElement.Id = existingTag.Id
-			} else {
+			if !exists {
 				_, err := sess.Table("tag").Insert(tagElement)
 				if err != nil {
+					if s.db.GetDialect().IsUniqueConstraintViolation(err) {
+						_, err := s.innerGetTag(sess, tagElement)
+						return err
+					}
+
 					return err
 				}
 			}
@@ -32,3 +34,17 @@ func (s *sqlStore) EnsureTagsExist(ctx context.Context, tags []*tag.Tag) ([]*tag
 	})
 	return tags, err
 }
+
+func (s *sqlStore) innerGetTag(sess *db.Session, tagElement *tag.Tag) (bool, error) {
+	var existingTag tag.Tag
+	exists, err := sess.Table("tag").Where("`key`=? AND `value`=?", tagElement.Key, tagElement.Value).Get(&existingTag)
+	if err != nil {
+		return false, err
+	}
+	if !exists {
+		return false, nil
+	}
+
+	tagElement.Id = existingTag.Id
+	return true, nil
+}