Mattermost Integration
Connect MailFellow to your Mattermost server to receive email notifications with interactive message buttons. You can view emails, resolve threads, assign to team members, and send new emails, all from Mattermost.
Features
- Email notifications with markdown formatting (sender, subject, category, snippet)
- Interactive message buttons: View, Resolve, Send Thanks, Assign, Block Sender, Delete
- Native Mattermost threading (reply chains)
- Real-time events via WebSocket (reactions, new messages)
- Send new emails with a guided flow
- Quick replies, assign, and unassign via text commands
- Message update and deletion support
- Automatic translation display for non-English emails
- Checkmark reaction (:white_check_mark:) to trigger reply
Connecting Mattermost
- Go to Settings > Channel
- Select Mattermost as the platform
- Enter the Channel ID of the channel where you want to receive emails
- Click Save
Tip: To find the Channel ID, click the channel name in Mattermost and look at the URL:
https://mattermost.example.com/team/channels/channel-idSelf-hosted? You will need to create a bot account and configure the token and server URL. See Getting Credentials > Mattermost for the full setup guide.
Available Commands
Type these in the channel or in a thread reply:
| Command | Description |
|---|---|
send email | Start a guided flow to send a new email |
quick <shortcut> | Reply with a saved quick response |
assign | Assign the thread to yourself |
assign @username | Assign to a specific team member |
unassign | Remove assignment |
Reactions
React to any email message with the :white_check_mark: (✅) emoji to trigger a reply action. This works the same way as in Discord and Slack.
WebSocket Connection
MailFellow connects to Mattermost via WebSocket for real-time events (new messages, reactions). The connection automatically reconnects if interrupted. No additional configuration is needed. The WebSocket URL is derived from your server URL.
Tip: If MailFellow is behind a reverse proxy, make sure WebSocket connections are allowed through (e.g.
proxy_set_header Upgrade $http_upgrade; in Nginx).Troubleshooting
Bot not posting messages
- Ensure the bot user has been added to the target channel
- Check that the Channel ID is correct in Settings
Action buttons not working
- Ensure Enable Interactive Messages is enabled in Mattermost System Console
- Verify MailFellow is reachable from the Mattermost server at
/api/mattermost/action
WebSocket disconnections
- MailFellow auto-reconnects after 5 seconds. Check network connectivity between MailFellow and Mattermost.
- Ensure your reverse proxy supports WebSocket upgrades.