Github Action: Create Tag and Release when a pull request is merged into master/main branch with release notes parsed from merge comment

01_github-action-create-release-on-merge.md

This Github Action workflow along with the rest of these files/scripts will allow you to create a Tag as well as a Release with the release notes set to the text added in the body of the merge comment when a pull request is merged.

Note:

Merge comment title needs to contain the text "release" or else the workflow will not run (see line 11 of create-release.yml).

02_index.php

<?php

  // This workflow assumes that you're setting the version of your software using a constant as defined below
  // Adjust get-version.sh file as needed 

	define( 'PREFIX_SOFTWARE_VERSION', '2.0.0' );

  //
  // Code 
  //

03_get-version.sh

#!/bin/bash
INPUT=$(grep PREFIX_SOFTWARE_VERSION index.php)
SUBSTRING=$(echo $INPUT| cut -d "'" -f 4 )
echo v$SUBSTRING

04_create-release-notes-file.php

<?php

$commit_message = getenv( "COMMITTEXT" );

// Merge commit message has two new lines after title, this is set automatically by Github
$commit_message_parts = explode( "\n\n", $commit_message );

// Get everything after the commit message title
$commit_message_body = $commit_message_parts[1];

// Push commit message body (fix, changes etc ) into an array for formatting
$commit_message_body_lines = explode( "\n", $commit_message_body );

$release_notes = '';

foreach( $commit_message_body_lines as $commit_message_body_line ){
    // Format Markdown
    $release_notes .= '* ' . $commit_message_body_line . PHP_EOL;
}

// Write to file
file_put_contents( 'release_notes.txt', $release_notes );
exit;

05_create-release.yml

name: Create Release

on:
  push:
    branches:
      - main

jobs:
  create-release:
    runs-on: ubuntu-latest
    if: contains( github.event.head_commit.message, 'release' )
    steps:
     - name: Checkout Code
       uses: actions/checkout@v2
     - name: Setup PHP
       uses: shivammathur/setup-php@v2
       with: 
          php-version: '7.4'
     - name: Create Release Notes File
       env: 
        COMMITTEXT: "${{ github.event.head_commit.message }}"
       run: |
          php create-release-notes-file.php
     - name: Set Tag Output
       id: set-tag
       run:  echo "::set-output name=tag_name::$(sh get-version.sh)"
     - name: Create Tag
       uses: actions/github-script@v3
       env:
          TAG: ${{ steps.set-tag.outputs.tag_name }}
       with:
          github-token: ${{ github.token }}
          script: |
            github.git.createRef({
              owner: context.repo.owner,
              repo: context.repo.repo,
             ref: "refs/tags/${{ steps.set-tag.outputs.tag_name }}",
              sha: context.sha
            })
     - name: Create release
       uses: ncipollo/release-action@v1
       with:
        tag: ${{ steps.set-tag.outputs.tag_name }}
        bodyFile: './release_notes.txt'
        token: ${{ secrets.GITHUB_TOKEN }}