Mattermost — Send Mattermost messages. Fork/inspired from https://github.com/apex/actions/tree/master/slack

For the message format you can check the Mattermost documentation

You can use it as below:

on: [push, pull_request]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: mattermost/action-mattermost-notify@master
        with:
          MATTERMOST_WEBHOOK_URL: ${{ secrets.MM_WEBHOOK_URL }}
          MATTERMOST_CHANNEL: the-best-channel
          TEXT: |
            This is a message from ${{ github.repository }}.
            [Pipeline](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}) was completed :white_check_mark:
          MATTERMOST_USERNAME: ${{ github.triggering_actor }}
          MATTERMOST_ICON_URL: https://cdn3.iconfinder.com/data/icons/system-basic-vol-4-1/20/icon-note-attention-alt3-512.png

or alternatively you can use the PAYLOAD input:

on: [push, pull_request]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: mattermost/action-mattermost-notify@master
        with:
          MATTERMOST_WEBHOOK_URL: ${{ secrets.MM_WEBHOOK_URL }}
          PAYLOAD: |-
            {
              "text": "What a message from ${{ github.repository }}",
              "channel": "the-best-channel",
              "username": "${{ github.triggering_actor }}",
              "icon": "https://cdn3.iconfinder.com/data/icons/system-basic-vol-4-1/20/icon-note-attention-alt3-512.png"
            }

The action.yml file defines metadata about your action, such as input(s) and output(s). For details about this file, see Metadata syntax for GitHub Actions.

When you copy this repository, update action.yml with the name, description, inputs, and outputs for your action.

The src/ directory is the heart of your action! This contains the source code that will be run when your action is invoked. You can replace the contents of this directory with your own code.

There are a few things to keep in mind when writing your action code:

• Most GitHub Actions toolkit and CI/CD operations are processed asynchronously. In main.js, you will see that the action is run in an async function.

  const core = require('@actions/core')
  //...
  
  async function run() {
    try {
      //...
    } catch (error) {
      core.setFailed(error.message)
    }
  }

  For more information about the GitHub Actions toolkit, see the documentation.

So, what are you waiting for? Go ahead and start customizing your action!

1. Create a new branch

   git checkout -b releases/v1

2. Replace the contents of src/ with your action code

3. Add tests to __tests__/ for your source code

4. Format, test, and build the action

   npm run all

5. Commit your changes

   git add .
   git commit -m "My first action is ready!"

6. Push them to your repository

   git push -u origin releases/v1

7. Create a pull request and get feedback on your action

8. Merge the pull request into the main branch

Your action is now published! 🚀

For information about versioning your action, see Versioning in the GitHub Actions toolkit.