Expo Preview Action Fails with pull_request Event

[IZUMI-Zu]

Topic and Issue

When using the expo/expo-github-action with the preview command in GitHub Actions. This setup is necessary for securely handling sensitive tokens like EXPO_TOKEN, especially for external contributors. However:

• Using pull_request event instead results in external contributors not having access to EXPO_TOKEN, causing the error: "Skipped authentication: 'token' not provided."

My setup is basically the same as the example:

on: [pull_request]
jobs:
  preview:
    runs-on: ubuntu-latest
    steps:
      - name: 🏗 Setup repo
        uses: actions/checkout@v3
      - name: 🏗 Setup Node
        uses: actions/setup-node@v3
        with:
          node-version: 18.x
          cache: yarn
      - name: 🏗 Setup EAS
        uses: expo/expo-github-action@v8
        with:
          eas-version: latest
          token: ${{ secrets.EXPO_TOKEN }}
      - name: 📦 Install dependencies
        run: yarn install
      - name: 🚀 Create preview
        uses: expo/expo-github-action/preview@v8
        with:
          command: eas update --auto --branch pr-${{ github.event.number }}

Motivation

We want to set up an action that automatically comments on pull requests with preview links when contributors open a PR. This would allow for quick review by maintainers.

Is there a better way to achieve our goal of automatically creating and commenting Expo previews on pull requests, while maintaining security for external contributions? We're open to alternative approaches or configurations that might solve this issue.