bug: send_video ignores caption and other opts when sending by file_id

[Kotazver]

Hi! I found a bug in api.send_video function. When sending a video, the caption field is ignored by Telegram because it's being sent in the query parameters (first table of api.request), while the video itself is sent as multipart/form-data (second table). According to Telegram Bot API, when using multipart/form-data, all parameters should be included in the multipart body.

[wrxck]

Hi @Kotazver thanks for letting me know, I'll take a look!

[wrxck]

Fix submitted in #31. The root cause was that api.request used next(file) to process the file table, which only extracts a single entry. When methods like send_video pass both the media file and a thumbnail (e.g., { video = video, thumbnail = opts.thumbnail }), only one entry was processed — the other was silently dropped. Depending on Lua's hash table ordering, this could lose either the media or the thumbnail.

Fixed by iterating all file entries with a for loop. Also fixed send_reply, input_text_message_content, and send_inline_article using the deprecated 'markdown' parse mode instead of 'MarkdownV2', and added missing question_parse_mode/question_entities params to send_poll.

Version bumped to 3.1-0.

[wrxck]

Hi @Kotazver, thanks for the detailed report! This has been fixed in v3.1 (PR #31).

Root cause: api.request() used next(file) which only processes one entry from the file table. When methods like send_video pass both video and thumbnail, only one was included in the multipart request — the rest of the parameters (caption, parse_mode, etc.) were silently dropped.

Fix: Replaced next(file) with a for loop to iterate all file entries, so all parameters are correctly included in the multipart-encoded request body.

Available via LuaRocks: luarocks install telegram-bot-lua 3.1-0