delete-pr-build-on-close.yml

name: Delete pre-release when a branch is deleted
# This workflow action deletes pre-releases when a PR is merged or closed.
#
# The CircleCI configuration builds CLI binaries when a PR is opened.
# These are uploaded to the upstream project as GitHub (pre-)releases.
#
# The release tag matches one of the following patterns:
#  - v1.2.3-example-branch-placeholder  # Branches on upstream
#  - v1.2.3-pull-12-head                # Branches from forks
#
# A "pull_request_target" event is used to delete pre-releases upstream.
#
# See https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#running-your-pull_request-workflow-when-a-pull-request-merges
# See https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows#pull_request_target
on:
  pull_request_target: # zizmor: ignore[dangerous-triggers]
    types:
      - closed

jobs:
  delete-pre-release:
    name: Delete pre-release if exists
    runs-on: ubuntu-latest
    permissions:
      contents: write
    steps:
      - name: Delete pre-release and tag named after branch
        env:
          GH_TOKEN: ${{ github.token }}
          PR_BRANCH: ${{ github.event.pull_request.head.ref }}
          PR_NUMBER: ${{ github.event.pull_request.number }}
          PR_REPO: ${{ github.event.pull_request.head.repo.full_name }}
        shell: bash
        run: |
          # Use either an upstream or fork PR branch
          if [[ "$PR_REPO" != "slackapi/slack-cli" ]]; then
            BRANCH="pull/$PR_NUMBER/head"
          else
            BRANCH="$PR_BRANCH"
          fi

          # Escape tags to create a semantic version
          REF=$(echo "${BRANCH}" | sed 's/\//-/g')
          RELEASE_FOUND=1

          # Delete tags matching the pull request branch from forks
          if GH_DEBUG=1 gh release --repo="slackapi/slack-cli" delete "${REF}" -y --cleanup-tag; then
            echo "Successfully deleted ${REF}"
            RELEASE_FOUND=0
          else
            echo "Did not find ${REF} tag, trying version prefixes..."
          fi

          # Figure out tag name from branch name. This is coupled to the tag name generation that exists in .circleci/config.yml's `create-github-release` job.
          RELEASES=$(gh release list --repo="slackapi/slack-cli" --order="desc" --json="tagName" --exclude-drafts --exclude-pre-releases --limit=24 --jq ".[] | .tagName")
          for TAGS in $RELEASES; do
            TAG_NAME="${TAGS}-${REF}"
            echo "Identified pre-release tagname to 🔪: $TAG_NAME"

            # Delete the pre-release
            if GH_DEBUG=1 gh release --repo="slackapi/slack-cli" delete "$TAG_NAME" -y --cleanup-tag; then
              echo "Successfully deleted $TAG_NAME"
              RELEASE_FOUND=0
            else
              echo "Failed to find $TAG_NAME, trying next..."
            fi
            sleep 1

            FEATURE_TAG_NAME="${TAGS}-${REF}-feature"
            echo "Identified feature-release tagname as 🔪: $FEATURE_TAG_NAME"

            # Delete a feature-release
            if GH_DEBUG=1 gh release --repo="slackapi/slack-cli" delete "$FEATURE_TAG_NAME" -y --cleanup-tag; then
              echo "Successfully deleted $FEATURE_TAG_NAME"
              RELEASE_FOUND=0
            else
              echo "Failed to find $FEATURE_TAG_NAME, trying next..."
            fi
            sleep 1
          done
          if [ "$RELEASE_FOUND" -ne 0 ]; then
            echo "No matching pre-releases tag was found for the branch $TAG_NAME in recent versions"
          fi
          exit "$RELEASE_FOUND"