update-formula.yml

name: create PR to update formula

on:
  push:
    branches:
      - imgpkg-homebrew
permissions:
  pull-requests: write
  contents: none
  actions: none
  checks: none
  deployments: none
  issues: none
  packages: none
  repository-projects: none
  security-events: none
  statuses: none
jobs:
  update-imgpkg-homebrew:
    runs-on: ubuntu-latest
    steps:
    - name: Checkout
      uses: actions/checkout@v2
      with:
        repository: vmware-tanzu/homebrew-carvel
        ref: develop
    - name: pull-request
      env:
        INPUT_SOURCE_BRANCH: "imgpkg-homebrew"
        INPUT_DESTINATION_BRANCH: "develop"
        INPUT_PR_TITLE: "Update imgpkg homebrew Formula: ${{ github.ref }}"
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      run: |
        set -e
        set -o pipefail

        if [[ -z "$GITHUB_TOKEN" ]]; then
          echo "Set the GITHUB_TOKEN environment variable."
          exit 1
        fi

        if [[ ! -z "$INPUT_SOURCE_BRANCH" ]]; then
          SOURCE_BRANCH="$INPUT_SOURCE_BRANCH"
        elif [[ ! -z "$GITHUB_REF" ]]; then
          SOURCE_BRANCH=${GITHUB_REF/refs\/heads\//}  # Remove branch prefix
        else
          echo "Set the INPUT_SOURCE_BRANCH environment variable or trigger from a branch."
          exit 1
        fi

        DESTINATION_BRANCH="${INPUT_DESTINATION_BRANCH:-"master"}"

        # Github actions no longer auto set the username and GITHUB_TOKEN
        git remote set-url origin "https://$GITHUB_ACTOR:$GITHUB_TOKEN@github.com/$GITHUB_REPOSITORY"

        # Pull all branches references down locally so subsequent commands can see them
        git fetch origin '+refs/heads/*:refs/heads/*' --update-head-ok

        # Print out all branches
        git --no-pager branch -a -vv

        if [ "$(git rev-parse --revs-only "$SOURCE_BRANCH")" = "$(git rev-parse --revs-only "$DESTINATION_BRANCH")" ]; then
          echo "Source and destination branches are the same."
          exit 0
        fi

        # Do not proceed if there are no file differences, this avoids PRs with just a merge commit and no content
        LINES_CHANGED=$(git diff --name-only "$DESTINATION_BRANCH" "$SOURCE_BRANCH" -- | wc -l | awk '{print $1}')
        if [[ "$LINES_CHANGED" = "0" ]] && [[ ! "$INPUT_PR_ALLOW_EMPTY" ==  "true" ]]; then
          echo "No file changes detected between source and destination branches."
          exit 0
        fi


        # Workaround for `hub` auth error https://github.com/github/hub/issues/2149#issuecomment-513214342
        export GITHUB_USER="$GITHUB_ACTOR"

        PR_ARG="$INPUT_PR_TITLE"
        if [[ ! -z "$PR_ARG" ]]; then
          PR_ARG="-m \"$PR_ARG\""

          if [[ ! -z "$INPUT_PR_TEMPLATE" ]]; then
            sed -i 's/`/\\`/g; s/\$/\\\$/g' "$INPUT_PR_TEMPLATE"
            PR_ARG="$PR_ARG -m \"$(echo -e "$(cat "$INPUT_PR_TEMPLATE")")\""
          elif [[ ! -z "$INPUT_PR_BODY" ]]; then
            PR_ARG="$PR_ARG -m \"$INPUT_PR_BODY\""
          fi
        fi

        if [[ ! -z "$INPUT_PR_REVIEWER" ]]; then
          PR_ARG="$PR_ARG -r \"$INPUT_PR_REVIEWER\""
        fi

        if [[ ! -z "$INPUT_PR_ASSIGNEE" ]]; then
          PR_ARG="$PR_ARG -a \"$INPUT_PR_ASSIGNEE\""
        fi

        if [[ ! -z "$INPUT_PR_LABEL" ]]; then
          PR_ARG="$PR_ARG -l \"$INPUT_PR_LABEL\""
        fi

        if [[ ! -z "$INPUT_PR_MILESTONE" ]]; then
          PR_ARG="$PR_ARG -M \"$INPUT_PR_MILESTONE\""
        fi

        if [[ "$INPUT_PR_DRAFT" ==  "true" ]]; then
          PR_ARG="$PR_ARG -d"
        fi

        COMMAND="hub pull-request \
          -b $DESTINATION_BRANCH \
          -h $SOURCE_BRANCH \
          --no-edit \
          $PR_ARG \
          || true"

        echo "$COMMAND"

        PR_URL=$(sh -c "$COMMAND")
        if [[ "$?" != "0" ]]; then
          exit 1
        fi

        echo ${PR_URL}
        echo "::set-output name=pr_url::${PR_URL}"
        echo "::set-output name=pr_number::${PR_URL##*/}"
        if [[ "$LINES_CHANGED" = "0" ]]; then
          echo "::set-output name=has_changed_files::false"
        else
          echo "::set-output name=has_changed_files::true"
        fi