Post Merged PRs to Mattermost

This GitHub Action collects all pull requests merged in the last 24 hours for the current repository and posts a formatted list to a Mattermost channel via an incoming webhook.

Features

• Uses the GitHub CLI (gh) to query merged PRs.
• Automatically detects the current repository ($GITHUB_REPOSITORY).
• Outputs a nicely formatted list including PR number, title, URL, and author.
• Sends the result to Mattermost using a webhook.
• If no PRs were merged in the last 24h, it posts a fallback message.

Inputs

Name	Required	Description
mattermost_webhook_url	Yes	Incoming webhook URL for your Mattermost channel.
gh_token	Yes	GitHub token (usually secrets.GITHUB_TOKEN) to authenticate with the GitHub CLI.
hours	No	How many hours back to search for merged PRs. (default: 24)
skip_if_no_prs	No	If it is true, skip sending if there is no prs

Example Usage

name: post-merged-prs
on:
  schedule:
    - cron: "0 0 * * *" # Runs daily at 00:00 UTC
  workflow_dispatch:

jobs:
  post-prs:
    runs-on: ubuntu-latest
    steps:
      - uses: Gen5HQ/mattermost-github-watcher@[version]
        with:
          mattermost_webhook_url: ${{ secrets.MATTERMOST_WEBHOOK_URL }}
          gh_token: ${{ secrets.GITHUB_TOKEN }}

How to get MATTERMOST_WEBHOOK_URL

Output Example

If PRs were merged in the last 24h, the Mattermost message will look like:

If no PRs were merged:

Requirements

• The GitHub CLI is preinstalled on GitHub-hosted runners.
• This action must have permission to read pull requests. By default, secrets.GITHUB_TOKEN is sufficient.