action.yml

# This Action checks Pull Request Titles, and updates them if they don't start with a Jira-ticket-formatted string
name: First Commit Jira to GitHub PR Title Updater
description: I make sure GitHub PR Titles start with a Jira ticket (and find it in first commit if I need to). Else, exit 1

# Permit being called from other Actions
on: workflow_call

jobs:
  pr_title_validate_and_update:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
        with:
          fetch-depth: 0
          ref: '${{ github.event.pull_request.base.ref }}'
      
      - name: Check and Update PR Title
        id: check_and_update_pr_title
        run: |

          ###
          # Set vars
          ###

          # If local_testing = true, set vars
          if [[ $local_testing == true ]]; then
            # If running locally for tesing
            GH_ORG="kymidd"
            GH_REPO="TestingPRUpdater"
            PR_TITLE="$PR_TITLE"
            GITHUB_TOKEN="$GITHUB_TOKEN"
            PULL_REQUEST_NUMBER=2
            BASE_BRANCH="main"
          else
            # If running as an Action
            GH_ORG="${{ github.repository_owner }}"
            GH_REPO=$(echo ${{ github.repository }} | cut -d "/" -f 2)
            PR_TITLE="${{ github.event.pull_request.title }}"
            GITHUB_TOKEN="${{ secrets.GITHUB_TOKEN }}"
            PULL_REQUEST_NUMBER="${{ github.event.pull_request.number }}"
            BASE_BRANCH="${{ github.event.pull_request.base.ref }}"
          fi


          ###
          # Functions
          ### 

          print_break() {
            # Print a break in the output
            echo ""
            echo "----------------------------------------"
            echo ""
          }

          exit_if_not_local() {
            # If not running locally, exit 
            if [[ $local_testing != true ]]; then
              print_break
              exit $1
            else

              echo "🔴 Running locally, not exiting with code $1, press any key to continue"

              # Wait for keypress to continue
              while true; do
                read -rsn1 key # Read a single character silently
                if [ $? = 0 ]; then
                  echo -e "\n$key is pressed, continuing"
                  break # Exit the loop
                else
                  echo "Waiting for a keypress"
                fi
              done

              print_break
            fi
          }

          update_pr_title() {
            echo "🟢 New PR title will be: $PR_TITLE"
            unset CURL
            CURL=$(curl -s \
              -X PATCH \
              -H "Accept: application/vnd.github+json" \
              -H "Authorization: Bearer $GITHUB_TOKEN" \
              -H "X-GitHub-Api-Version: 2022-11-28" \
              https://api.github.com/repos/$GH_ORG/$GH_REPO/pulls/$PULL_REQUEST_NUMBER \
              -d "{\"title\":\"$PR_TITLE\"}" 2>&1 || true)
              if [[ $(echo "$CURL" | jq -r '.title') == $PR_TITLE ]]; then
              echo "🟢 Successfully updated PR title"
              exit_if_not_local 0
            else
              echo "🔴 Something bad happened updating the PR title, please investigate response:"
              echo "$CURL"
              exit_if_not_local 1
            fi
          }


          ###
          # Check vars required to run
          ###

          if [[ -z $GH_ORG || -z $GH_REPO || -z $PR_TITLE || -z $GITHUB_TOKEN || -z $PULL_REQUEST_NUMBER || -z $BASE_BRANCH ]]; then
            echo "🔴 One or more variables are undefined, exiting"
            exit_if_not_local 1
          fi


          ###
          # Start
          ###

          print_break
          echo "🟢 The title of your pull request is currently $PR_TITLE"


          ###
          # Normalize inputs
          ### 

          # Capitalize the PR_TITLE to make regex matches easier downstream
          NORMALIZED_PR_TITLE=$(echo $PR_TITLE | tr '[:lower:]' '[:upper:]')


          ###
          # Look at PR commits, find first one, extract commit message
          ###

          # Checkout the PR branch
          git checkout -q "${{ github.event.pull_request.head.ref }}"

          # Find current branch name
          CURRENT_BRANCH=$(git branch | grep ^\* | cut -d "*" -f 2 | cut -d " " -f 2)

          # Find hash of commit most common ancestor, e.g. where branch began
          BRANCH_MERGE_BASE=$(git merge-base ${BASE_BRANCH} ${CURRENT_BRANCH})

          # Find all commits since common ancestor
          BRANCH_COMMITS=$(git rev-list ${BRANCH_MERGE_BASE}..HEAD)

          # Find first commit, extract commit message and then Jira ticket number
          FIRST_COMMIT=$(echo $BRANCH_COMMITS | head -n 1)
          FIRST_COMMIT_MESSAGE=$(git log --max-count=1 --format=%B "$FIRST_COMMIT" | awk 'NF')
          NORMALIZED_FIRST_COMMIT_MESSAGE=$(echo $FIRST_COMMIT_MESSAGE | tr '[:lower:]' '[:upper:]')
          JIRA_TICKET=$(echo $NORMALIZED_FIRST_COMMIT_MESSAGE | grep -o -E '^[A-Z]{2,}-[0-9]+' || true)

          # If commit message doesn't start with Jira ticket, exit
          if [ -z "$JIRA_TICKET" ]; then
            # No Jira ticket found in title at all, exit with failure code
            echo "🔴 No Jira ticket found at beginning of PR title or at beginning of first commit message."
            echo "🔴 Please update your PR title. You'll also likely need to \"git commit --amend\" your first commit message so Jira Commit Checker Action will succeed"
            print_break
            exit_if_not_local 1
          fi


          ###
          # Check if first commit matches PR title
          ###

          # Check if first commit matches PR title
          if [[ $PR_TITLE == $FIRST_COMMIT_MESSAGE ]]; then
            echo "🟢 First commit message matches PR title, no changes triggered"
            exit_if_not_local 0
          else
            echo "🔴 First commit message doesn't match PR title, updating PR title"
            print_break
            
            # Set new PR title to value of first commit message
            PR_TITLE="$FIRST_COMMIT_MESSAGE"
            update_pr_title
          fi