Skip to main content

​
Create a Slack app

  1. Go to api.slack.com/apps and select Create New App.
  2. Choose Starter app and select the Slack workspace where the app will run.
  3. Open OAuth & Permissions. Under Bot Token Scopes, add chat:write.

​
Enable incoming webhooks

  1. In your app settings, open Incoming Webhooks.
  2. Turn on Activate Incoming Webhooks.
  3. Select Add New Webhook to Workspace. Choose the channel where Midway should post and authorize the app.
  4. Copy the generated webhook URL.
Each incoming webhook is tied to the channel selected when it is created. Slack grants the incoming-webhook permission as part of creating the webhook; this is separate from the chat:write bot scope. You can create additional webhooks for other channels from Incoming Webhooks.

​
Add the webhook to Midway

Run the Midway setup command and paste the webhook URL when prompted:
By default, Midway sends notifications to all configured methods. To restrict delivery, define notification.send_to and include Slack; configured methods left out of the list will not receive notifications. With pick_from: All, Midway sends through every method listed there:
pick_from can further select a subset of the methods in send_to for each notification. The current setup prompt accepts one webhook URL per configuration. Creating additional Slack webhooks does not add more Midway prompts; use a separate configuration for another channel. You can also add the webhook URL directly to midway.yaml under tokens.slack:
Slack may limit message delivery from apps that have not been published or distributed. Limits can depend on Slack’s current policies, so check Slack’s documentation before relying on an unpublished app for high-volume notifications.
Slack generally limits message posting to one message per second per channel, including messages sent through incoming webhooks. Short bursts may be allowed, but sustained higher-volume posting can be rate-limited. Some API methods have additional limits for certain non-Marketplace apps. See Slack’s rate limit documentation for current details.