- Create a Slack app
- Enable the Bot user, add
chat:write
andchannels:read
in Permissions>Scopes, and generate an OAuth token for it - Deploy to DigitalOcean using the token and signing secret from steps (1) and (2)
- Go back to the Slack App config and click on Event Subscriptions
- Enable and paste your app's URL in the Request URL field like so:
https://yourapp.ondigitalocean.app/slack/events
- Subscribe to the bot event
channel_created