Reintroduce max_telegram_delete

pkg/connector/config.go

@@ -93,6 +93,7 @@ type TelegramConfig struct {
 	ContactAvatars                       bool                `yaml:"contact_avatars"`
 	ContactNames                         bool                `yaml:"contact_names"`
 	MaxMemberCount                       int                 `yaml:"max_member_count"`
+	MaxTelegramDelete                    int                 `yaml:"max_telegram_delete"`
 	AlwaysCustomEmojiReaction            bool                `yaml:"always_custom_emoji_reaction"`
 	SavedMessagesAvatar                  id.ContentURIString `yaml:"saved_message_avatar"`
 	AlwaysTombstoneOnSupergroupMigration bool                `yaml:"always_tombstone_on_supergroup_migration"`
@@ -107,6 +108,10 @@ func (c TelegramConfig) ShouldBridge(participantCount int) bool {
 	return c.MaxMemberCount < 0 || participantCount <= c.MaxMemberCount
 }
 
+func (c TelegramConfig) ShouldBridgeDeletion(deletedMessageCount int) bool {
+	return c.MaxTelegramDelete < 0 || deletedMessageCount <= c.MaxTelegramDelete
+}
+
 type DisplaynameParams struct {
 	FullName  string
 	FirstName string
@@ -185,6 +190,7 @@ func upgradeConfig(helper up.Helper) {
 	helper.Copy(up.Bool, "contact_avatars")
 	helper.Copy(up.Bool, "contact_names")
 	helper.Copy(up.Int, "max_member_count")
+	helper.Copy(up.Int, "max_telegram_delete")
 	helper.Copy(up.Bool, "always_custom_emoji_reaction")
 	helper.Copy(up.Str, "saved_message_avatar")
 	helper.Copy(up.Bool, "always_tombstone_on_supergroup_migration")

pkg/connector/example-config.yaml

@@ -96,6 +96,12 @@ takeout:
 #
 # -1 means no limit (which means all chats can be bridged)
 max_member_count: -1
+# The maximum number of simultaneous Telegram message deletions to handle.
+# If a single Telegram update deletes more than this many messages, the entire
+# deletion is ignored instead of being bridged as Matrix redactions.
+#
+# -1 means no limit
+max_telegram_delete: -1
 # Should personal avatars (that are only visible to specific users) be allowed?
 contact_avatars: false
 # Should contact names be updated from any source even if a name is already set?

pkg/connector/handletelegram.go

@@ -795,7 +795,18 @@ func (tc *TelegramClient) onUserName(ctx context.Context, e tg.Entities, update
 }
 
 func (tc *TelegramClient) onDeleteMessages(ctx context.Context, channelID int64, update IGetMessages) error {
-	for _, messageID := range update.GetMessages() {
+	messages := update.GetMessages()
+
+	if !tc.main.Config.ShouldBridgeDeletion(len(messages)) {
+		zerolog.Ctx(ctx).Info().
+			Int64("channel_id", channelID).
+			Int("deleted_message_count", len(messages)).
+			Int("max_telegram_delete", tc.main.Config.MaxTelegramDelete).
+			Msg("Ignoring mass deletion of messages on Telegram to preserve the Matrix history")
+		return nil
+	}
+
+	for _, messageID := range messages {
 		wrappedMessageID := ids.MakeMessageID(channelID, messageID)
 		var portalKey networkid.PortalKey
 		var ok bool