An action that closes all PRs by new contributors and marks them as invalid.

stop-hacktoberfest-spam.yml

name: Stop Hacktoberfest Spam

on:
  pull_request_target:

jobs:
  stop-spam:
    runs-on: ubuntu-latest

    steps:
      - name: Check if it's a new contributor
        # Based on https://github.com/actions/github-script#welcome-a-first-time-contributor
        id: new-contributor
        uses: actions/github-script@626af12fe9a53dc2972b48385e7fe7dec79145c9 # 3.0.0
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          result-encoding: string
          script: |
            const creator = context.payload.sender.login
            const opts = github.issues.listForRepo.endpoint.merge({
              ...context.issue,
              creator,
              state: 'all'
            })
            const issues = await github.paginate(opts)

            for (const issue of issues) {
              if (issue.number === context.issue.number) {
                continue
              }

              if (issue.pull_request) {
                return false // Creator is already a contributor.
              }
            }
            
            return true
      
      - name: Post friendly comment
        if: steps.new-contributor.outputs.result == 'true'
        uses: actions/github-script@626af12fe9a53dc2972b48385e7fe7dec79145c9 # 3.0.0
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            github.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: 'ADD A MESSAGE HERE THAT EXPLAINS WHY THE PR WILL BE AUTOCLOSED.'
            })
      
      - name: Label as invalid
        if: steps.new-contributor.outputs.result == 'true'
        uses: actions/github-script@626af12fe9a53dc2972b48385e7fe7dec79145c9 # 3.0.0
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            github.issues.addLabels({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              labels: ['invalid']
            })
          
      - name: Close PR
        if: steps.new-contributor.outputs.result == 'true'
        uses: actions/github-script@626af12fe9a53dc2972b48385e7fe7dec79145c9 # 3.0.0
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            github.pulls.update({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.issue.number,
              state: 'closed'
            })