Howl

Because somebody should yell at you when your master build breaks.

howl is a tool that sends messages to Slack or Discord when your default branch build fails, typically on main or master. It is designed to be triggered on your CI (continuous integration) system when a failure occurs on your default branch. You can use it as a GitHub Action or as a standalone program, which can be installed with Hermit.

Slack setup

Set up a GitHub secret called SLACK_WEBHOOK_URL with your Slack Webhook URL, for example

https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX

Optional inputs

To use a channel other than the default channel set up in the Slack App bound to the webhook, set the SLACK_CHANNEL environment variable, for example

export SLACK_CHANNEL=C0000000000

For a more customized message or @-mentions, set the SLACK_TEXT environment variable, for example

export SLACK_TEXT="<!here> 🚒"

Discord setup

Set up a GitHub secret called DISCORD_WEBHOOK_URL with your Discord Webhook URL for the target discord channel, for example

https://discord.com/api/webhooks/1000000000000000000/XXXXXXXX-xxxxxxxxxxxxxxxxx

Optional inputs

For a more customized message or @-mentions, set the DISCORD_TEXT environment variable, for example

export DISCORD_TEXT="@here 🚒"

Local Testing

You can test the integration locally with

export SLACK_WEBHOOK_URL=https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX
export DISCORD_WEBHOOK_URL=https://discord.com/api/webhooks/1000000000000000000/XXXXXXXX-xxxxxxxxxxxxxxxxx'
howl

GitHub Action usage

Use the foxygoat/howl@v2 in you GitHub Actions Workflow that runs on the default branch, for example:

name: ci
on:
  push:
    branches: [main]

jobs:
  ci:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        run: make ci
  howl-on-fail:
    runs-on: ubuntu-latest
    needs: [ci]
    if: always() && contains(join(needs.*.result, ','), 'failure')
    steps:
      - uses: foxygoat/howl@v2
        with:
          slack-webhook-url: ${{ secrets.SLACK_WEBHOOK_URL }}
          slack-channel: C0000000000 # optional; channel ID
          slack-text: <!here> # optional; text or @-mention
          discord-webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
          discord-text: '@here' # optional; text or @-mention