action.yaml

name: "cleanlab/merge-bot"
description: "Deployment merge handler."
author: "Ryan Singman @ Cleanlab"
inputs:
  reviews_required: 
    description: "if reviews are required to merge"
    required: false
    default: true
  dependent_checks:
    description: "comma separated list of checks to depend on"
    required: false
    default: ""
  check_status_required:
    description: "status value(s) for check to be considered passed (as comma separated list)"
    required: false
    default: "success"
  blocking_label:
    description: "label to block merge on (leave empty to disable behavior)"
    required: false
    default: ""
  delete_branch:
    description: "if should delete source branch of PR after successful merge"
    required: false
    default: false
  merge_type:
    description: "type of merge to use (merge or fast-forward)"
    required: true
  github_token:
    description: "token used to access source repository"
    required: true
  

runs:
  using: composite

  steps:
    - uses: actions/checkout@v3

    - id: blocking_label_check
      run: |
        python $GITHUB_ACTION_PATH/merge_bot/check_blocking_label.py \
        --blocking-label ${{ inputs.blocking_label }} \
        --labels ${{ join(github.event.pull_request.labels.*.name, ' ') }} && \
        echo "success=1" >> $GITHUB_OUTPUT || \
        echo "success=0" >> $GITHUB_OUTPUT
      shell: bash

    # install Python dependencies for action
    - run: |
        pip install -r $GITHUB_ACTION_PATH/requirements.txt
      shell: bash

    # if reviews_required, check all reviews are passing
    - id: review_check
      if: ${{ inputs.reviews_required }}
      run: |
        GITHUB_TOKEN=${{ inputs.github_token }} \
        python $GITHUB_ACTION_PATH/merge_bot/check_review_approval.py \
        --repository ${{ github.repository }} \
        --pull-request-number ${{ github.event.pull_request.number }} && \
        echo "success=1" >> $GITHUB_OUTPUT || \
        echo "success=0" >> $GITHUB_OUTPUT
      shell: bash

    # if dependent checks, check all checks have required check status
    - id: dependents_check
      if: ${{ inputs.dependent_checks }}
      run: |
        GITHUB_TOKEN=${{ inputs.github_token }} \
        python $GITHUB_ACTION_PATH/merge_bot/check_dependent_checks.py \
        --checks "${{ inputs.dependent_checks }}" \
        --repository ${{ github.repository }} \
        --head-sha ${{ github.event.pull_request.head.sha }} \
        --passing-check-statuses ${{ inputs.check_status_required }} && \
        echo "success=1" >> $GITHUB_OUTPUT || \
        echo "success=0" >> $GITHUB_OUTPUT
      shell: bash

    # merge PR using merge type
    - id: merge
      if: ${{ steps.blocking_label_check.outputs.success == 1 && steps.review_check.outputs.success == 1 && steps.dependents_check.outputs.success == 1 }}
      uses: everlytic/branch-merge@1.1.5
      with:
        github_token: ${{ inputs.github_token }}
        source_ref: ${{ github.event.pull_request.head.ref }}
        target_branch: ${{ github.event.pull_request.base.ref }}
      continue-on-error: true
    
    # if delete source branch, delete branch
    - if: ${{ success() && inputs.delete_branch && steps.merge.outcome == 'success' }}
      run: |
        echo "${{ steps.merge }}"
        echo "Deleting source branch: ${{ github.event.pull_request.head.ref }}"
        git push --delete origin ${{ github.event.pull_request.head.ref }}
      shell: bash

    # if failed to merge, print message
    - if: failure()
      run:
        echo "Failed to merge -- exiting."
        exit 0
      shell: bash