action.yml

name: Auto-tag
description: Automatically delete and re-release tags so that other github action modules can use something similar to carets e.g. v0.1 or v3

runs:
  using: composite
  steps:

    - name: Checkout code
      uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4.2.1
      with:
        fetch-depth: 0
      if: ${{ github.event_name == 'workflow_dispatch' }}

    - name: Install PHP
      uses: shivammathur/setup-php@c541c155eee45413f5b09a52248675b1a2575231 # v2.31.1
      with:
        php-version: 8.1

    - name: Generate tag name
      id: generate_tag_name
      shell: bash
      env:
        GITHUB_REF: ${{ github.ref }}
        GITHUB_REPOSITORY: ${{ github.repository }}
        GITHUB_EVENT_NAME: ${{ github.event_name }}
      run: |
        # refs/tags/0.1.23 => 0.1.23
        TAG=""
        if [[ $GITHUB_EVENT_NAME == 'push' ]]; then
          # Use the current tag name the workflow was triggered on
          echo "Getting tag from github.ref"
          TAG=$(echo $GITHUB_REF | cut -c 11-)
          if ! [[ $TAG =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]; then
            echo "Invalid semver tag $TAG"
            exit 1
          fi
          echo "TAG is $TAG"
          MAJOR="${BASH_REMATCH[1]}"
          MINOR="${BASH_REMATCH[2]}"
        else
          echo "Getting tag from github api"
          # Find the highest semver tag on repo
          # Gets 100 most recently created tags from GitHub API
          # https://docs.github.com/en/rest/git/tags?apiVersion=2022-11-28
          RESP_CODE=$(curl -w %{http_code} -s -o __tags.json \
          -X GET "https://api.github.com/repos/$GITHUB_REPOSITORY/tags?per_page=100" \
          -H "Accept: application/vnd.github+json" \
          -H "Authorization: Bearer ${{ github.token }}" \
          -H "X-GitHub-Api-Version: 2022-11-28")
          if [[ $RESP_CODE != "200" ]]; then
              echo "Unable to read list of tags - HTTP response code was $RESP_CODE"
              cat __tags.json
              exit 1
          fi
          # Get highest semver tag from list
          TAG=$(php -r '
              $json = json_decode(file_get_contents("__tags.json"), true);
              $tags = [];
              foreach ($json as $record) {
                  if (preg_match("#^[0-9]+\.[0-9]+\.[0-9]+$#", $record["name"])) {
                      $tags[] = $record["name"];
                  }
              }
              usort($tags, "version_compare");
              echo $tags[count($tags) - 1] ?? "";
          ')
          if [[ $TAG == "" ]]; then
              echo "Unable to find any semver tags on repo"
              cat __tags.json
              exit 1
          fi
          echo "TAG is $TAG"
          [[ $TAG =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]
          # Ensure we are on the correct branch prior to tagging
          MAJOR="${BASH_REMATCH[1]}"
          MINOR="${BASH_REMATCH[2]}"
          git checkout $MAJOR.$MINOR
          if [[ $? != 0 ]]; then
              echo "Branch $MAJOR.$MINOR does not exist"
              exit 1
          fi
        fi
        NEW_TAG="v${MAJOR}"
        if [ "$MAJOR" == "0" ]; then
          NEW_TAG=("v${MAJOR}.${MINOR}")
        fi
        echo "NEW_TAG is $NEW_TAG"
        echo "new_tag=$NEW_TAG" >> "$GITHUB_OUTPUT"

    - name: Add tag to repo
      uses: silverstripe/gha-tag-release@v2
      with:
        skip_gauge_release: true
        tag: ${{ steps.generate_tag_name.outputs.new_tag }}
        delete_existing: true
        release: false

    - name: Delete temporary files
      shell: bash
      if: always()
      run: |
        if [[ -f __tags.json ]]; then
          rm __tags.json
        fi