PR Preview Deployments

Automatically deploy preview builds for each pull request. The preview mode auto-generates an undername from the PR number and posts a comment with the preview URL:

name: Deploy PR Preview

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  deploy-preview:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'

      - name: Install dependencies
        run: npm ci

      - name: Build
        run: npm run build

      - name: Deploy Preview
        uses: ar-io/ar-io-deploy@v2.0.0
        with:
          deploy-key: ${{ secrets.DEPLOY_KEY }}
          arns-key: ${{ secrets.ARNS_KEY }}
          arns-name: myapp
          preview: 'true'
          github-token: ${{ secrets.GITHUB_TOKEN }}
          deploy-folder: ./dist

When preview is enabled, the action will:

Auto-generate an undername like myapp-repo-pr-123 from the repository name and PR number
Post a comment on the PR with the preview URL (the token needs pull-requests: write)
Update the comment on subsequent pushes instead of creating new ones

Preview undernames are not removed when the PR closes; each costs one of the ArNS name's undername slots until you remove it. The action skips every step on a closed event, so subscribing to it costs nothing.

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