Companion to 4.6.2 (VOD chat replay): when capturing a live stream,
also open an anonymous IRC connection to Twitch chat and append every
message to a sibling .chat.jsonl file. Closes the symmetry — VOD
downloads get .chat.json, live recordings get .chat.jsonl. Both
formats are deliberate: VOD pulls finite, JSON-array friendly; live
streams are open-ended, JSON Lines friendly so a kill mid-stream
preserves prior data.
Server:
- new LiveChatSession + startLiveChatCapture / stopLiveChatCapture.
Opens a TLS connection to irc.chat.twitch.tv:6697, anonymous
Twitch auth (NICK justinfan{rand}, no PASS), JOINs the channel,
enables CAP twitch.tv/tags + commands so we get badges, color,
display-name, etc.
- IRC line parser: minimal — split tags / prefix / command / params,
handle PRIVMSG (chat), USERNOTICE (subs/raids), CLEARCHAT,
CLEARMSG. Each parsed message is one JSON object on its own line:
{ t, type, u, login, color, msg, badges, bits, msgId, systemMsg }.
Per-line write keeps memory flat — a 12-hour stream's chat could
be hundreds of MB; we never hold more than one batch in RAM.
- File handle is opened up-front (so a write failure surfaces early),
always closed on the close event.
- PING/PONG handling so Twitch doesn't ratelimit the connection out.
- Header line written at session start so an empty-chat capture
still produces a valid file with metadata.
Wire-up:
- downloadLiveStream starts the session BEFORE streamlink (so the
first JOIN messages aren't lost) and stops it AFTER streamlink
exits (so trailing reactions still get logged). Failures inside
the chat session do NOT mark the recording as failed — the video
is still fine. The chat file path is added to outputFiles when it
exists so the existing Open file / Show in folder UI lists both.
Renderer / settings:
- new capture_live_chat: boolean (default off). Settings -> Download
card gets the toggle with hint.
- AppConfig type, autosave fingerprint, syncSettingsForm, locale
strings (DE + EN).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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