gitlab-actions/templates/pre-commit.yml

spec:
  inputs:
    as_job:
      type: string
      default: pre-commit
      description: The name of the job that will be included with this component.
    stage:
      default: .pre
      type: string
      description: The stage in which the job should run.
    image:
      type: string
      default: python:3.12-slim
      description: The container image to use for the job.
    autofix:
      type: boolean
      default: false
      description: If pre-commit should fix and push the changed. Requires token.
    access_token:
      type: string
      default: $CI_JOB_TOKEN
    deduplicate_mr_and_branch:
      type: boolean
      default: true
---
$[[ inputs.as_job ]]:
  stage: "$[[ inputs.stage ]]"
  image: "$[[ inputs.image ]]"
  variables:
    PRE_COMMIT_AUTO_FIX: "$[[ inputs.autofix ]]"
    PRE_COMMIT_DEDUPLICATE_MR_AND_BRANCH: "$[[ inputs.deduplicate_mr_and_branch ]]"
    PRE_COMMIT_ACCESS_TOKEN: "$[[ inputs.access_token ]]"
  script:
    - echo "Using image $[[ inputs.image ]] with ${CI_COMMIT_REF_SLUG}@${CI_COMMIT_SHORT_SHA}"
    - |
      # Ensure programms are installed
      if ! command -v git &> /dev/null; then
        echo "Installing git..."
        apt-get update > /dev/null
        apt-get install git --yes --no-install-recommends > /dev/null 2>&1
      fi
      if ! command -v pre-commit &> /dev/null; then
        echo "Installing pre-commit..."
        pip install --no-cache-dir pre-commit > /dev/null 2>&1
      fi
    - |
      # Running pre-commit
      if [[ -n "$PRE_COMMIT_AUTO_FIX_BRANCH_ONLY" && -n "$PRE_COMMIT_AUTO_FIX_MR_ONLY" ]]; then
          echo "invalid configuration. PRE_COMMIT_AUTO_FIX_BRANCH_ONLY and PRE_COMMIT_AUTO_FIX_MR_ONLY are mutually exclusive"
          exit 1
      fi

      status=0
      pre-commit run --all-files || status=$?
      if [[ $status -ne 0 ]]; then
          if [[ -n "$CI_COMMIT_BRANCH" ]]; then
              git remote set-url origin "https://gitlab-ci-token:${PRE_COMMIT_ACCESS_TOKEN:-$CI_JOB_TOKEN}@${CI_SERVER_HOST}/${CI_PROJECT_PATH}.git"
              git fetch origin
              git checkout $CI_COMMIT_BRANCH
          fi
          if [[ -n "$CI_MERGE_REQUEST_IID" ]]; then
              git remote set-url origin "https://gitlab-ci-token:${PRE_COMMIT_ACCESS_TOKEN:-$CI_JOB_TOKEN}@${CI_SERVER_HOST}/${CI_MERGE_REQUEST_SOURCE_PROJECT_PATH}.git"
              git fetch origin
          fi
          pre-commit run --all-files  # check the status passes now with autofix otherwise, it'll fail
      else
          exit 0  # we're all good
      fi

      if [[ "$PRE_COMMIT_AUTO_FIX" != "true" ]]; then
          exit 1 # fail the job
      fi

      git config --global user.email "$GITLAB_USER_EMAIL"
      git config --global user.name "$GITLAB_USER_NAME"

      # proceed with auto-fix
      if [[ -z "$PRE_COMMIT_ACCESS_TOKEN" ]]; then
          echo "Auto-fix is enabled, but no pre-commit access token found." >> /dev/stderr
          echo "To enable automatic fixes, please create a project access token with repository write scope and set the PRE_COMMIT_ACCESS_TOKEN variable" > /dev/stderr
          exit 1
      fi

      if [[ -n "$CI_COMMIT_BRANCH" ]]; then
          git add -u .
          git commit -m "auto fixes from pre-commit CI job" -m "job url: $CI_JOB_URL"
          git push
          exit 1
      elif [[ -n "$CI_MERGE_REQUEST_IID" ]]; then
          git add -u .
          git commit -m "auto fixes from pre-commit CI job" -m "job url: $CI_JOB_URL"
          git push origin HEAD:"$CI_MERGE_REQUEST_SOURCE_BRANCH_NAME"
          exit 1
      else
         echo "Auto fix is not supported in this context" > /dev/stderr
         echo "Auto fix is only available in branch and merge request pipelines" > /dev/stderr
         exit 1
      fi
  rules:
    - if: "$PRE_COMMIT_SKIP_BRANCH_PIPELINE && $CI_COMMIT_BRANCH"
      when: never
    - if: '$PRE_COMMIT_SKIP_MR_PIPELINE && $CI_PIPELINE_SOURCE == "merge_request_event"'
      when: never
    - if: '$PRE_COMMIT_AUTO_FIX_BRANCH_ONLY && $CI_PIPELINE_SOURCE == "merge_request_event"'
      variables:
        PRE_COMMIT_AUTO_FIX: ""
      when: on_success
      exists:
        - .pre-commit-config.yaml
    - if: '$PRE_COMMIT_DEDUPLICATE_MR_AND_BRANCH == "true" && $CI_COMMIT_BRANCH && $CI_OPEN_MERGE_REQUESTS'
      when: never
    - if: '$PRE_COMMIT_AUTO_FIX_MR_ONLY && $CI_PIPELINE_SOURCE != "merge_request_event"'
      variables:
        PRE_COMMIT_AUTO_FIX: ""
      exists:
        - .pre-commit-config.yaml
      when: on_success
    - if: '$CI_PIPELINE_SOURCE == "merge_request_event" && $CI_MERGE_REQUEST_EVENT_TYPE != "detached"'
      variables: # we don't support autofix for merged_result or merge_train pipelines, configure branch fixing instead
        PRE_COMMIT_AUTO_FIX: ""
      exists:
        - .pre-commit-config.yaml
    - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
      exists:
        - .pre-commit-config.yaml
      when: on_success
    - if: "$CI_COMMIT_BRANCH"
      exists:
        - .pre-commit-config.yaml
      when: on_success
    - when: never