close_merge_request.yml

name: Close MR on GitLab

on:
  pull_request:
    types: [closed]

jobs:
  close-merge-request:
    runs-on: ubuntu-latest
    steps:
      - name: close-merge-request
        env:
          GITLAB_API_ACCESS_TOKEN: ${{ secrets.GITLAB_API_ACCESS_TOKEN }}
          GITLAB_API: ${{ secrets.GITLAB_API }}
          GITLAB_PROJECT_ID: ${{ secrets.GITLAB_PROJECT_ID }}
          PR_SOURCE_BRANCH: ${{ github.head_ref }}
          PR_TARGET_BRANCH: ${{ github.base_ref }}
        run: |
          echo "PR_SOURCE_BRANCH: $PR_SOURCE_BRANCH"
          echo "PR_TARGET_BRANCH: $PR_TARGET_BRANCH"
          MR_IID=`curl \
            --header "Content-Type: application/json" \
            --header "PRIVATE-TOKEN: $GITLAB_API_ACCESS_TOKEN" \
            "$GITLAB_API/projects/$GITLAB_PROJECT_ID/merge_requests?state=opened&source_branch=$PR_SOURCE_BRANCH&target_branch=$PR_TARGET_BRANCH" \
            | jq '.[0].iid'`
          curl \
            --request PUT \
            --header "Content-Type: application/json" \
            --header "PRIVATE-TOKEN: $GITLAB_API_ACCESS_TOKEN" \
            "$GITLAB_API/projects/$GITLAB_PROJECT_ID/merge_requests/$MR_IID?state_event=close"