Slack Notify GitHub Action

Learn how to automate Slack notifications directly from your GitHub Actions workflows using the Slack Notify action by rtCamp. By the end of this guide, you’ll be able to send build statuses, deployment alerts, and custom messages to any Slack channel.

Table of Contents

1. Action Inputs Reference
2. Creating a Slack Channel & Webhook
3. Testing Your Webhook
4. Storing the Webhook as a GitHub Secret
5. Adding the Slack Notification Job
6. Verifying Notifications in Slack
7. Using if: always() on Cancellation
8. Links and References

Action Inputs Reference

Use the following environment variables to configure your Slack messages. At minimum, set SLACK_CHANNEL and SLACK_WEBHOOK.

Example Usage

- name: Slack Notification
  uses: rtCamp/action-slack-notify@v2
  env:
    SLACK_CHANNEL: general
    SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
    SLACK_COLOR: ${{ job.status }}
    SLACK_ICON: https://github.com/rtCamp.png?size=48
    SLACK_TITLE: Build Notification
    SLACK_MESSAGE: 'Build Status :rocket:'
    SLACK_USERNAME: rtCamp

Creating a Slack Channel & Webhook

1. In your Slack workspace, create a new channel (e.g., github-actions-channel).
2. Navigate to https://api.slack.com/apps and click Create New App → From scratch.
3. Name the app GitHub Actions application, select your workspace, then Create App.
4. Under Features, enable Incoming Webhooks and click Add to Workspace.
5. Choose your channel and click Allow. Copy the generated webhook URL.

Testing Your Webhook

Before integrating into GitHub Actions, verify the webhook:

curl -X POST -H 'Content-type: application/json' \
  --data '{"text":"Hello, World!"}' YOUR_WEBHOOK_URL_HERE

Storing the Webhook as a GitHub Secret

1. In your GitHub repository, go to Settings > Secrets and variables > Actions.
2. Click New repository secret, name it SLACK_WEBHOOK, and paste your webhook URL.

Adding the Slack Notification Job

Incorporate the Slack notification at the end of your workflow to report statuses on success, failure, or cancellation. Below is a sample workflow:

on:
  push:
    branches:
      - main
      - 'feature/*'

env:
  MONGO_URI: 'mongodb+srv://supercluster.d83jj.mongodb.net/superData'
  MONGO_USERNAME: ${{ vars.MONGO_USERNAME }}
  MONGO_PASSWORD: ${{ secrets.MONGO_PASSWORD }}

jobs:
  unit-testing:
    # ...
  code-coverage:
    # ...
  dev-integration-testing:
    # ...
  prod-integration-testing:
    # ...

  slack-notification:
    if: always()
    name: Slack Notification
    needs: [dev-integration-testing, prod-integration-testing]
    continue-on-error: true
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Send Slack Notification
        uses: rtCamp/action-slack-notify@v2
        env:
          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
          SLACK_CHANNEL: github-actions-channel
          SLACK_COLOR: ${{ job.status }}
          SLACK_ICON: https://gitlab.com/sidd-harth/solar-system/-/raw/main/images/saturn.png
          SLACK_TITLE: Workflow Status
          SLACK_MESSAGE: ':hammer_and_wrench: Triggered by ${{ github.actor }}'

After the run completes, view the summary:

Verifying Notifications in Slack

Open your Slack channel (github-actions-channel) and confirm receipt of the notification:

Using if: always() on Cancellation

By using if: always(), your Slack notification step will run even if the workflow is manually canceled or fails. See GitHub Actions expressions for more details.

When you cancel the workflow mid-run, the notification still fires:

Links and References

• rtCamp/action-slack-notify GitHub Repository
• Slack Incoming Webhooks Documentation
• GitHub Actions Expressions
• GitHub Docs: Secrets