This sample application demonstrates how to build a modern chat interface using DigitalOcean's GenAI Platform. It features real-time streaming responses, WebSocket communication, and proper authentication.

The AuthService handles authentication with the DigitalOcean GenAI Platform:

• Validates required environment variables
• Manages the Agent Access Key securely
• Provides the key for API authentication

The ChatService manages the chat functionality:

• Maintains WebSocket connections for real-time communication
• Handles message streaming from the AI
• Manages chat sessions and conversation history
• Processes incoming messages and outgoing responses

The application uses Express Session middleware for secure session handling:

• Authenticates WebSocket connections using session IDs
• Maintains user state across page refreshes
• Protects against session hijacking and tampering
• Uses SESSION_SECRET to sign and encrypt session data

• Node.js 18 or higher
• npm
• A DigitalOcean GenAI Platform account with:
  • An Agent Key (found in Settings > Endpoint Access Keys)
  • An Agent Endpoint URL

Create a .env file in the root directory:

# For local development only, App Platform will set PORT automatically
PORT=3000

# Required environment variables
AGENT_KEY=your-agent-key         # Created in Settings > Endpoint Access Keys
AGENT_ENDPOINT=your-agent-endpoint # Your agent's endpoint URL (must end with /api/v1/)
SESSION_SECRET=your-secret-key    # Long random string for session security

Important Notes:

1. The SESSION_SECRET should be:

   • A long, random string (at least 32 characters recommended)
   • Different between development and production environments
   • Kept secret and never committed to version control
   • Changed if potentially compromised

2. When deploying to DigitalOcean App Platform:

   • Do not set the PORT variable (managed automatically)
   • Set a strong SESSION_SECRET in the environment variables
   • Keep the SESSION_SECRET consistent across app instances

# Install dependencies
npm install

# Run tests
npm test

# Start development server
npm run dev

# Start production server
npm start

The application includes comprehensive tests for all major components:

# Run all tests
npm test

# Run tests in watch mode
npm run test:watch

# Run tests with coverage
npm run test:coverage

To deploy this application on DigitalOcean:

1. App Platform Setup:

   • Deploy as a single container/instance to maintain WebSocket connections
   • Set all environment variables listed above

2. GenAI Platform Requirements:

   • Create an AI Agent in your DigitalOcean account
   • Navigate to Settings > Endpoint Access Keys
   • Create a new access key and copy it to your environment variables
   • Copy the Endpoint URL from the agent settings

For detailed instructions on setting up and using AI Agents, please refer to:

• DigitalOcean GenAI Platform Documentation
• How to Use Agents Documentation

• Real-time streaming responses
• WebSocket-based communication
• Secure authentication
• Session persistence
• Markdown support in chat
• Code syntax highlighting
• Dark/Light theme support
• Mobile-responsive design

• Never commit your .env file
• Always use a strong SESSION_SECRET
• The application validates all required environment variables on startup
• WebSocket connections are authenticated using session IDs
• Access tokens are managed securely in memory

ISC License