action.yml

name: "git-config-from-token"
author: "Marco Ieni"
description: "Configure the git user corresponding to the `GITHUB_TOKEN` environment variable."
branding:
  icon: "zap"
  color: "yellow"
outputs:
  name:
    description: "Git author name"
    value: ${{ steps.git-author.outputs.name }}
  email:
    description: "Git author email"
    value: ${{ steps.git-author.outputs.email }}
runs:
  using: "composite"
  steps:
    - id: git-author
      name: Determine Git user info from GitHub token
      shell: bash
      run: |
        if [ -z "${GITHUB_TOKEN+x}" ]; then
          echo "Error: environment variable GITHUB_TOKEN is undefined"
          exit 1
        fi

        if [ -z "$GITHUB_TOKEN" ]; then
          echo "Error: environment variable GITHUB_TOKEN is empty"
          exit 1
        fi

        # The environment variable GITHUB_TOKEN is read by the `gh` cli
        VIEWER_JSON=$(gh api graphql -f query='query { viewer { name login databaseId }}' --jq '.data.viewer')
        VIEWER_NAME=$(jq --raw-output '.name | values' <<< "${VIEWER_JSON}")
        VIEWER_LOGIN=$(jq --raw-output '.login' <<< "${VIEWER_JSON}")
        VIEWER_DATABASE_ID=$(jq --raw-output '.databaseId' <<< "${VIEWER_JSON}")

        # Set the variable USER_NAME to the value of VIEWER_NAME if VIEWER_NAME is set and not null.
        # Otherwise, set USER_NAME to the value of VIEWER_LOGIN.
        USER_NAME="${VIEWER_NAME:-${VIEWER_LOGIN}}"
        USER_EMAIL="${VIEWER_DATABASE_ID}+${VIEWER_LOGIN}@users.noreply.github.com"

        git config --global user.name "${USER_NAME}"
        git config --global user.email "${USER_EMAIL}"

        echo "name=${USER_NAME}" >> "${GITHUB_OUTPUT}"
        echo "email=${USER_EMAIL}" >> "${GITHUB_OUTPUT}"