create-pr-when-pr-is-merged.yml

name: create-pr-when-pr-is-merged

on:
  pull_request:
    types:
      - closed
    branches:
      - main

env:
  BRANCH_NAME: random-update-in-readme
  BASE_BRANCH_NAME: main

jobs:
  create-pr-if-outdated:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@44c2b7a8a4ea60a981eaca3cf939b5f4305c123b # v4
        with:
          ref: ${{ env.BASE_BRANCH_NAME }}

      - name: update date in readme
        run: |
          echo "github PR number: ${{ github.event.pull_request.number }}"
          sed -i "s/.*Last Merged PR: \(.*\)/- Last Merged PR: #${{ github.event.pull_request.number }}/" README.md

      - name: leave a comment to the original PR
        uses: actions/github-script@v7
        with:
          script: |
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: `GitHub Actions has been triggered: https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}`
            })

      - name: check if need to commit
        id: need_commit
        run: |
          if [[ -n "$(git status --porcelain)" ]]; then
            echo "need_commit=true" >> "$GITHUB_OUTPUT"
          else
            echo "need_commit=false" >> "$GITHUB_OUTPUT"
          fi

      - name: commit and push
        if: steps.need_commit.outputs.need_commit == 'true'
        run: |
          git config user.name github-actions
          git config user.email github-actions@github.com
          git checkout -b ${{ env.BRANCH_NAME }}
          git add .
          git commit -m 'update date'
          git push -u origin HEAD -f

      - name: check if pr exists
        id: check_pr
        if: steps.need_commit.outputs.need_commit == 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }} # used by gh
        run: |
          # echo "count=$(gh pr list -S head:${{ env.BRANCH_NAME }} -B ${{ env.BASE_BRANCH_NAME }} | wc -l)" >> "$GITHUB_OUTPUT"
          pulls=$(curl -s -H "Accept: application/vnd.github.v3+json" -H "Authorization: token ${{ secrets.GITHUB_TOKEN }}" "https://api.github.com/repos/nakamasato/github-actions-practice/pulls?head=nakamasato:${{ env.BRANCH_NAME }}&base=${{ env.BASE_BRANCH_NAME }}")
          echo "$pulls | jq length"
          count=$(echo "$pulls" | jq length)
          pr_number=$(echo "$pulls" | jq '.[].number')
          echo "pr_number=$pr_number" >> "$GITHUB_OUTPUT"
          echo "count=$count" >> "$GITHUB_OUTPUT"

      - name: create pr
        if: ${{ steps.need_commit.outputs.need_commit == 'true' && steps.check_pr.outputs.count == 0 }}
        uses: octokit/request-action@v2.x
        id: create_pr
        with:
          route: POST /repos/${{ github.repository }}/pulls
          title: | # https://github.com/octokit/request-action/issues/118#issuecomment-913823682
            |-
              chore: create pr for random update
          head: nakamasato:${{ env.BRANCH_NAME }}
          base: ${{ env.BASE_BRANCH_NAME }}
          body: | # https://github.com/octokit/request-action#inputs
            |
            # What
            Update readme
            # Why
            To check GitHub Actions (triggered by #${{ github.event.pull_request.number }})
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      - name: get pull request number from new pull request
        if: ${{ steps.need_commit.outputs.need_commit == 'true' && steps.check_pr.outputs.count == 0 }}
        id: get_pr_number_from_new_pr
        run:
          echo "pr_number=${{ fromJson(steps.create_pr.outputs.data).number }}" >> "$GITHUB_OUTPUT"

      - name: get pull request number
        id: get_pr_number
        run: |
          if [[ ${{ steps.check_pr.outputs.pr_number }} != "" ]];then
            echo "pr_number=${{ steps.check_pr.outputs.pr_number }}" >> "$GITHUB_OUTPUT" # from existing pr
          else
            echo "pr_number=${{ steps.get_pr_number_from_new_pr.outputs.pr_number }}" >> "$GITHUB_OUTPUT" # from new pr
          fi

      - name: request reviwer
        if: steps.get_pr_number.outputs.pr_number != ''
        uses: octokit/request-action@v2.x
        with:
          route: POST /repos/${{ github.repository }}/pulls/${{ steps.get_pr_number.outputs.pr_number }}/requested_reviewers
          reviewers: "[\"${{ github.actor }}\"]" # the person who merges the pr
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      - name: leave a comment to the original PR
        if: steps.get_pr_number.outputs.pr_number != ''
        uses: actions/github-script@v7
        with:
          script: |
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: `## Pull Request\nPlease merge the PR #${{ steps.get_pr_number.outputs.pr_number }}`
            })