binder.yml

name: Build and Cache Binder Image

on:
  push:
    branches:
      - master
      - main
    paths:
      - 'binder/**'
      - 'pyproject.toml'
      - 'environment.yml'
      - 'requirements.txt'
  pull_request:
    types: [opened, reopened, synchronize]
    paths:
      - 'binder/**'
      - 'pyproject.toml'
      - 'environment.yml'
      - 'requirements.txt'

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Build and trigger binder cache
        uses: jupyterhub/repo2docker-action@master
        with:
          NO_PUSH: "true"
          MYBINDERORG_TAG: ${{ github.head_ref || github.ref_name }}

      - name: Comment on PR with Binder link
        if: github.event_name == 'pull_request'
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const BRANCH_NAME = '${{ github.head_ref || github.ref_name }}';
            const REPO = '${{ github.repository }}';
            const OWNER = REPO.split('/')[0];
            const REPO_NAME = REPO.split('/')[1];

            const BODY = `🚀 **Binder is ready!**

            [![Launch on Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/${OWNER}/${REPO_NAME}/${BRANCH_NAME}?urlpath=lab%2Ftree%2Fnotebooks%2Fdemo.ipynb)

            Click the badge above to launch the notebook.`;

            const { data: comments } = await github.rest.issues.listComments({
              owner: OWNER,
              repo: REPO_NAME,
              issue_number: context.issue.number
            });

            const binderComment = comments.find(c => c.body.includes('Binder is ready'));

            if (binderComment) {
              await github.rest.issues.updateComment({
                owner: OWNER,
                repo: REPO_NAME,
                comment_id: binderComment.id,
                body: BODY
              });
            } else {
              await github.rest.issues.createComment({
                owner: OWNER,
                repo: REPO_NAME,
                issue_number: context.issue.number,
                body: BODY
              });
            }