Add GitHub App authentication support

llama-index-integrations/readers/llama-index-readers-github/CHANGELOG.md

@@ -1,5 +1,31 @@
 # CHANGELOG
 
+## [0.9.0]
+
+### Added
+
+- **GitHub App Authentication**: Added support for authenticating via GitHub App as an alternative to Personal Access Tokens (PAT)
+  - New `GitHubAppAuth` class for handling GitHub App authentication with automatic token management
+  - All client classes (`GithubClient`, `GitHubIssuesClient`, `GitHubCollaboratorsClient`) now support `github_app_auth` parameter
+  - Automatic installation token caching with 5-minute expiry buffer (300 seconds)
+  - Token auto-refresh when near expiry
+  - JWT generation using RS256 algorithm for GitHub App authentication
+  - Optional dependency group `[github-app]` for installing PyJWT with cryptographic support
+  - Comprehensive test suite with 25 test cases covering all authentication scenarios
+  - Example script demonstrating GitHub App usage patterns
+  - Updated README with GitHub App setup guide and troubleshooting section
+
+### Changed
+
+- Client initialization now accepts either `github_token` (PAT) or `github_app_auth` (GitHub App), but not both
+- `_get_auth_headers()` method is now async to support dynamic token fetching for GitHub App authentication
+
+### Backward Compatibility
+
+- All existing PAT-based authentication code remains fully functional and unchanged
+- No breaking changes to existing APIs
+- All 19 existing tests continue to pass
+
 ## [0.1.2] - 2024-02-13
 
 - Add maintainers and keywords from library.json (llamahub)

llama-index-integrations/readers/llama-index-readers-github/GITHUB_APP_QUICKSTART.md

@@ -0,0 +1,217 @@
+# GitHub App Authentication - Quick Start Guide
+
+This guide will help you quickly set up and use GitHub App authentication with the llama-index-readers-github package.
+
+## Prerequisites
+
+1. **Install the package with GitHub App support:**
+
+   ```bash
+   pip install llama-index-readers-github[github-app]
+   ```
+
+2. **Create a GitHub App** (one-time setup):
+
+   - Go to GitHub Settings → Developer settings → GitHub Apps → New GitHub App
+   - Fill in required fields (name, homepage URL, webhook URL - can use placeholder)
+   - Set permissions:
+     - Repository permissions → Contents: Read-only
+     - (Optional) Issues: Read-only (if using issues reader)
+   - Click "Create GitHub App"
+   - **Note your App ID** from the app settings page
+
+3. **Generate a private key:**
+
+   - On your GitHub App settings page, scroll to "Private keys"
+   - Click "Generate a private key"
+   - Save the downloaded `.pem` file securely
+
+4. **Install the GitHub App:**
+   - Go to your GitHub App settings → Install App
+   - Choose which account/organization to install it on
+   - Select repositories (all or specific ones)
+   - **Note your Installation ID** from the URL: `https://github.com/settings/installations/{installation_id}`
+
+## Quick Start Code
+
+```python
+from llama_index.readers.github import GithubRepositoryReader, GitHubAppAuth
+
+# 1. Set up authentication
+github_app_auth = GitHubAppAuth(
+    app_id="123456",  # Your GitHub App ID
+    private_key=open("your-app.pem").read(),  # Your private key
+    installation_id="789012",  # Your installation ID
+)
+
+# 2. Create reader
+reader = GithubRepositoryReader(
+    owner="owner-name",
+    repo="repo-name",
+    github_app_auth=github_app_auth,
+)
+
+# 3. Load documents
+documents = reader.load_data(branch="main")
+print(f"Loaded {len(documents)} documents")
+```
+
+## Environment Variables Method
+
+For better security, use environment variables:
+
+```python
+import os
+from llama_index.readers.github import GithubRepositoryReader, GitHubAppAuth
+
+# Load from environment variables
+github_app_auth = GitHubAppAuth(
+    app_id=os.environ["GITHUB_APP_ID"],
+    private_key=os.environ["GITHUB_PRIVATE_KEY"],
+    installation_id=os.environ["GITHUB_INSTALLATION_ID"],
+)
+
+reader = GithubRepositoryReader(
+    owner="owner-name",
+    repo="repo-name",
+    github_app_auth=github_app_auth,
+)
+
+documents = reader.load_data(branch="main")
+```
+
+Set environment variables in your shell:
+
+```bash
+export GITHUB_APP_ID="123456"
+export GITHUB_INSTALLATION_ID="789012"
+export GITHUB_PRIVATE_KEY="$(cat your-app.private-key.pem)"
+```
+
+## Key Features
+
+### Automatic Token Management
+
+Tokens are automatically:
+
+- ✅ Fetched when first needed
+- ✅ Cached in memory
+- ✅ Refreshed before expiration (5-minute buffer)
+- ✅ Handled transparently - you don't need to worry about it!
+
+### Error Handling
+
+```python
+from llama_index.readers.github import (
+    GitHubAppAuth,
+    GitHubAppAuthenticationError,
+)
+
+try:
+    github_app_auth = GitHubAppAuth(
+        app_id="123456",
+        private_key="invalid-key",
+        installation_id="789012",
+    )
+    token = github_app_auth.get_installation_token()
+except GitHubAppAuthenticationError as e:
+    print(f"Authentication failed: {e}")
+```
+
+### Force Token Refresh
+
+```python
+# Manually refresh the token if needed
+github_app_auth.get_installation_token(force_refresh=True)
+
+# Invalidate cached token (useful if token is revoked)
+github_app_auth.invalidate_token()
+```
+
+### GitHub Enterprise Support
+
+```python
+github_app_auth = GitHubAppAuth(
+    app_id="123456",
+    private_key="...",
+    installation_id="789012",
+    github_base_url="https://github.your-company.com/api/v3",  # Your GHE URL
+)
+```
+
+## Common Issues
+
+### Issue: `ImportError: cannot import name 'GitHubAppAuth'`
+
+**Solution:** Install with GitHub App support:
+
+```bash
+pip install llama-index-readers-github[github-app]
+```
+
+### Issue: `GitHubAppAuthenticationError: Failed to generate JWT`
+
+**Solution:** Check that your private key is valid:
+
+- Should have RSA headers
+- Should be the complete key including header and footer
+- Should be the `.pem` file downloaded from GitHub
+
+### Issue: `401 Unauthorized` when fetching token
+
+**Possible causes:**
+
+- Invalid App ID
+- Invalid private key
+- Invalid Installation ID
+- App not installed in the target organization/account
+
+**Solution:** Verify your credentials:
+
+1. Check App ID in GitHub App settings
+2. Regenerate and download a new private key
+3. Reinstall the app and note the new Installation ID
+
+### Issue: `403 Forbidden` when accessing repository
+
+**Possible causes:**
+
+- GitHub App doesn't have access to the repository
+- Insufficient permissions
+
+**Solution:**
+
+1. Go to GitHub Settings → Installations
+2. Click "Configure" on your app
+3. Add the repository to the app's access list
+4. Ensure "Contents" permission is set to "Read"
+
+## Comparison: PAT vs GitHub App
+
+| Feature        | Personal Access Token (PAT) | GitHub App                           |
+| -------------- | --------------------------- | ------------------------------------ |
+| **Rate Limit** | 5,000 requests/hour         | 5,000 requests/hour per installation |
+| **Scope**      | User-level access           | Repository/organization-level        |
+| **Security**   | Broader access              | Granular permissions                 |
+| **Expiration** | Manual rotation             | Automatic (1-hour tokens)            |
+| **Audit Logs** | Limited                     | Detailed                             |
+| **Best For**   | Personal projects           | Team/enterprise use                  |
+
+## Next Steps
+
+- See `examples/github_app_example.py` for more detailed examples
+- Read the full README.md for advanced features
+- Check IMPLEMENTATION_SUMMARY.md for technical details
+
+## Support
+
+If you encounter issues:
+
+1. Check the troubleshooting section in README.md
+2. Verify your GitHub App setup
+3. Review error messages carefully
+4. Open an issue on the llama-index repository with details
+
+---
+
+**Pro Tip:** Store your private key securely (e.g., using a secrets manager or environment variables). Never commit `.pem` files to version control!