automation-create-pull-request.yaml

name: Generate Merge Log and Open Pull Request

on:
  workflow_call:
    inputs:
      repository-name:
        description: 'Repository name'
        required: true
        type: string
      main-branch:
        description: 'Main branch name'
        required: true
        type: string
      develop-branch:
        description: 'Develop branch name'
        required: true
        type: string
env:
  GH_TOKEN: ${{ github.token }}

jobs:
  generate-merge-log-and-open-pr:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout Repository
        uses: actions/checkout@v7
        with:
          fetch-depth: 0

      - name: Fetch Unmerged PRs
        id: fetch-unmerged-prs
        run: |
        
          git fetch --all
          
          # Get all the Pull Request head commits
          git fetch origin "+refs/pull/*/head:refs/remotes/origin/pr/*" &>/dev/null

          # Generate a list of all PR's contained in the specified branches
          git branch -r --merged origin/${{inputs.develop-branch}} | grep "origin/pr/*" | sort > inthis.txt
          git branch -r --merged origin/${{inputs.main-branch}} | grep "origin/pr/*" | sort > notinthis.txt
          
          # Clean up after getting all the PR head commits
          git remote prune origin &>/dev/null

          # Compare the lists of PR's contained in branches, and output result
          comm -23 inthis.txt notinthis.txt | sed "s,  origin/pr/,,g" > pr-numbers.txt
          
          # Clean up temp files
          rm inthis.txt
          rm notinthis.txt

      - name: Retrieve PR Info
        id: retrieve-pr-info
        run: |
          while read -r pr_number; do
            response=$(curl -s -o resp.json -H "Authorization: Bearer ${{ github.token }}" "https://api.github.com/repos/${{ inputs.repository-name }}/pulls/$pr_number")        
            
            if [[ $(cat resp.json | jq -r '.message') != "Not Found" ]]; then
              state=$(cat resp.json | jq -r '.state')
              merged=$(cat resp.json | jq -r '.merged')

               if [[ $state == "closed" && $merged == "true" ]]; then
                title=$(cat resp.json | jq -r '.title')
                date=$(cat resp.json | jq -r '.merged_at')
                user_handle=$(cat resp.json | jq -r '.user.login')
                merge_commit_sha=$(cat resp.json | jq -r '.merge_commit_sha')

                echo "#### $title (#$pr_number)" 
                echo "Merge commit SHA: $merge_commit_sha"
                echo "Author: @$user_handle"
                echo "Merged at: $date"
                echo ""
              fi
            fi
          done < pr-numbers.txt > prs.txt
          rm pr-numbers.txt
      - name: Fetch non-PR commits
        id: fetch-nonpr-commits
        run: |
          git fetch --all
          git log --no-merges --format="%s%nSHA: %H%nAuthor: %ae%nDate: %ad%n" --first-parent origin/${{ inputs.main-branch }}..origin/${{ inputs.develop-branch }} > commits.txt
      - name: Create Body Text
        id: create-body-text
        run: |
          touch body.txt
          if [[  -s prs.txt ]]; then
            echo "### Pull Requests" >> body.txt
            cat prs.txt >> body.txt
            echo >> body.txt
          fi
          if [[  -s commits.txt ]]; then
            echo "### Non-PR commits" >> body.txt
            cat commits.txt >> body.txt
            echo >> body.txt
          fi
          
          if [[ ! -s body.txt ]]; then
            echo "::warning::No changes found in ${{ inputs.develop-branch }} not found in ${{ inputs.main-branch }}. Skipping PR creation"
            exit 0
          fi

      - name: Create PR
        id: create-pr
        run: |
          if [[ -s body.txt ]]; then
            gh pr create --title "Automated PR - Merging ${{ inputs.develop-branch }} into ${{ inputs.main-branch }}" -F body.txt -B ${{ inputs.main-branch }} -H ${{ inputs.develop-branch }}
          fi