Add support for Mattermost (self-hosted Slack alternative) and Matrix
(federated messaging protocol) as messaging platforms.
Mattermost adapter:
- REST API v4 client for posts, files, channels, typing indicators
- WebSocket listener for real-time 'posted' events with reconnect backoff
- Thread support via root_id
- File upload/download with auth-aware caching
- Dedup cache (5min TTL, 2000 entries)
- Full self-hosted instance support
Matrix adapter:
- matrix-nio AsyncClient with sync loop
- Dual auth: access token or user_id + password
- Optional E2EE via matrix-nio[e2e] (libolm)
- Thread support via m.thread (MSC3440)
- Reply support via m.in_reply_to with fallback stripping
- Media upload/download via mxc:// URLs (authenticated v1.11+ endpoint)
- Auto-join on room invite
- DM detection via m.direct account data with sync fallback
- Markdown to HTML conversion
Fixes applied over original PR #1225 by @cyb0rgk1tty:
- Mattermost: add timeout to file downloads, wrap API helpers in
try/except for network errors, download incoming files immediately
with auth headers instead of passing auth-required URLs
- Matrix: use authenticated media endpoint (/_matrix/client/v1/media/),
robust m.direct cache with sync fallback, prefer aiohttp over httpx
Install Matrix support: pip install 'hermes-agent[matrix]'
Mattermost needs no extra deps (uses aiohttp).
Salvaged from PR #1225 by @cyb0rgk1tty with fixes.
cd67f60e01