# Mock GDS MCP Server

A **Remote MCP** (Model Context Protocol) server that simulates Global Distribution System (GDS) functionality for testing and demonstration purposes. Uses **MCP 2025-11-25 Streamable HTTP** transport (HTTP/1.1 + Server-Sent Events).

## ⚠️ IMPORTANT SAFETY NOTICE

**THIS IS A MOCK SERVER FOR TESTING AND DEMONSTRATION ONLY**

- ❌ Does NOT connect to real GDS systems
- ❌ Does NOT process real bookings or transactions
- ❌ Does NOT charge credit cards or process payments
- ✅ All bookings are simulated with `TEST-` prefixed PNRs
- ✅ Safe for development, testing, and training environments

See [SAFETY_DISCLAIMER.md](./SAFETY_DISCLAIMER.md) for complete details.

---

## Features

- **Remote MCP Access**: HTTP/1.1 + SSE transport per MCP 2025-11-25 specification
- **Flight Operations**: Search flights, create bookings, retrieve confirmations
- **Hotel Bookings**: Search and book hotels with realistic pricing
- **Car Rentals**: Search and book rental cars from major providers
- **Multi-Service Bundling**: Combined bookings under single PNR
- **Session Management**: Isolated sessions with UUID v4 IDs and TTL
- **Rate Limiting**: 100 requests/minute per IP (Valkey-backed)
- **Realistic Mock Data**: Valid IATA codes, realistic pricing, professional presentation
- **Docker Ready**: Multi-platform container images (amd64/arm64)

## Quick Start

### Prerequisites

- Node.js 20+ LTS
- Docker and Docker Compose (recommended)
- Valkey 8.0+ or Redis (for storage backend)

### Installation

#### Option 1: Docker Deployment (Recommended)

```bash
# Clone repository
git clone <repository-url>
cd gds-mock-mcp

# Build and start all services
docker compose up -d

# Verify health
curl http://localhost:3000/health
```

#### Option 2: Local Development

```bash
# Install dependencies
npm install

# Start Valkey
docker run -d --name valkey -p 6379:6379 valkey/valkey:8-alpine

# Start HTTP server
node src/index.js

```

### Testing the Server

```bash
# Check health
curl http://localhost:3000/health

# Initialize MCP session
curl -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "mcp-protocol-version: 2025-11-25" \
  -d '{
    "jsonrpc": "2.0",
    "method": "initialize",
    "id": 1,
    "params": {
      "protocolVersion": "2025-11-25",
      "capabilities": {},
      "clientInfo": {"name": "test-client", "version": "1.0.0"}
    }
  }'
```

**Environment Variables:**

You can customize deployment with environment variables:

```bash
# Custom port
PORT=8080 docker compose up -d

# Change log level
LOG_LEVEL=debug docker compose up -d

# Bind to specific host
HOST=0.0.0.0 docker compose up -d
```

## MCP Tools

The server provides **11 MCP tools** for travel booking operations:

### Flight Operations
- `searchFlights` - Search for available flights
- `bookFlight` - Book a flight with passenger details

### Hotel Operations
- `searchHotels` - Search for hotels by city
- `bookHotel` - Book a hotel room

### Car Rental Operations
- `searchCars` - Search for rental cars
- `bookCar` - Book a rental car

### Booking Management
- `retrieveBooking` - Get booking details by PNR
- `cancelBooking` - Cancel an existing booking
- `listBookings` - List all bookings in session

### Session Management
- `getSessionInfo` - Get current session information
- `clearSession` - Clear all bookings from session

## Usage Examples

### Health Check

```bash
curl http://localhost:3000/health
```

### 1. Initialize MCP Session

First, initialize to get a session ID:

```bash
curl -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "mcp-protocol-version: 2025-11-25" \
  -d '{
    "jsonrpc": "2.0",
    "method": "initialize",
    "id": 1,
    "params": {
      "protocolVersion": "2025-11-25",
      "capabilities": {},
      "clientInfo": {"name": "test-client", "version": "1.0.0"}
    }
  }'
```

**Extract the session ID from the response headers:**
```
< mcp-session-id: 550e8400-e29b-41d4-a716-446655440000
```

### 2. List Available Tools

```bash
# Use the session ID from step 1
SESSION_ID="550e8400-e29b-41d4-a716-446655440000"

curl -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "mcp-protocol-version: 2025-11-25" \
  -H "mcp-session-id: $SESSION_ID" \
  -d '{
    "jsonrpc": "2.0",
    "method": "tools/list",
    "id": 2,
    "params": {}
  }'
```

### 3. Search Flights

```bash
curl -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "mcp-protocol-version: 2025-11-25" \
  -H "mcp-session-id: $SESSION_ID" \
  -d '{
    "jsonrpc": "2.0",
    "method": "tools/call",
    "id": 3,
    "params": {
      "name": "searchFlights",
      "arguments": {
        "origin": "JFK",
        "destination": "LAX",
        "departureDate": "2026-05-01",
        "passengers": 1
      }
    }
  }'
```

## Architecture

### Remote MCP Transport

- **Protocol**: MCP 2025-11-25 Streamable HTTP
- **Transport**: HTTP/1.1 + Server-Sent Events (SSE)
- **Endpoint**: `/mcp` for all MCP operations
- **Session Management**: UUID v4 session IDs with 1-hour TTL

### Production Deployment

For production use, consider using Nginx as a reverse proxy to add:
- TLS/SSL encryption (HTTPS)
- HTTP/2 support for clients
- Additional rate limiting
- Request logging

See `docker/nginx.conf.example` for a sample Nginx configuration.

## Usage

### MCP Tool: searchFlights

Search for available flights between two airports.

**Input:**
```json
{
  "origin": "JFK",
  "destination": "LAX",
  "departureDate": "2026-06-15",
  "passengers": { "adults": 2 },
  "cabin": "economy"
}
```

**Output:**
```json
{
  "search": { "origin": "JFK", "destination": "LAX", "departureDate": "2026-06-15" },
  "results": [
    {
      "id": "flight-0-1234567890",
      "flightNumber": "AA123",
      "airlineCode": "AA",
      "airlineName": "American Airlines",
      "originCode": "JFK",
      "destinationCode": "LAX",
      "departureTime": "2026-06-15T08:00:00",
      "arrivalTime": "2026-06-15T11:30:00",
      "duration": 390,
      "cabin": "economy",
      "price": 29900,
      "seatsAvailable": 15,
      "bookingClass": "Y",
      "status": "available"
    }
  ],
  "resultCount": 5
}
```

### MCP Tool: bookFlight

Create a flight booking.

**Input:**
```json
{
  "flightId": "flight-0-1234567890",
  "passengers": [
    {
      "firstName": "John",
      "lastName": "Doe",
      "type": "adult",
      "email": "john.doe@example.com"
    }
  ],
  "contactEmail": "john.doe@example.com",
  "flightDetails": { /* full flight object from search */ }
}
```

**Output:**
```json
{
  "success": true,
  "pnr": "TEST-A1B2C3",
  "status": "confirmed",
  "message": "Flight booked successfully. PNR: TEST-A1B2C3",
  "booking": {
    "pnr": "TEST-A1B2C3",
    "passengers": [...],
    "flights": [...],
    "totalPrice": 29900,
    "currency": "USD"
  }
}
```

### MCP Tool: retrieveBooking

Retrieve booking details by PNR.

**Input:**
```json
{
  "pnr": "TEST-A1B2C3"
}
```

### MCP Tool: cancelBooking

Cancel an existing booking.

**Input:**
```json
{
  "pnr": "TEST-A1B2C3"
}
```

### MCP Tool: listBookings

List all bookings in current session.

**Input:**
```json
{
  "limit": 10,
  "offset": 0
}
```

## Configuration

Configuration is managed via environment variables. Copy `.env.example` to `.env` and customize:

```bash
cp .env.example .env
```

### Key Configuration Options

| Variable | Default | Description |
|----------|---------|-------------|
| `LOG_LEVEL` | `info` | Logging verbosity (silent, error, warn, info, debug, trace) |
| `VALKEY_HOST` | `localhost` | Valkey/Redis host |
| `VALKEY_PORT` | `6379` | Valkey/Redis port |
| `MCP_SESSION_TIMEOUT` | `3600` | Session timeout in seconds (1 hour) |
| `MOCK_DATA_SEED` | `random` | Data generation mode (random, fixed, demo) |

## Architecture

```
┌─────────────────┐
│  MCP Client     │
│  (CLI/Agent)    │
└────────┬────────┘
         │ stdio
         ▼
┌─────────────────┐
│  GDS Mock MCP   │
│  Server         │
│  (Node.js 20)   │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│  Valkey 8.0+    │
│  (Storage)      │
└─────────────────┘
```

## Project Structure

```
├── src/
│   ├── index.js           # Entry point
│   ├── server.js          # MCP server
│   ├── tools/             # MCP tool handlers
│   │   ├── flights.js     # Flight operations
│   │   └── bookings.js    # Booking management
│   ├── data/              # Mock data generators
│   │   ├── airports.js    # Airport data (100+ airports)
│   │   ├── airlines.js    # Airline data (30+ carriers)
│   │   ├── flights.js     # Flight generator
│   │   └── pnr.js         # PNR generation
│   ├── session/           # Session management
│   │   ├── manager.js     # Session lifecycle
│   │   └── storage.js     # Valkey client
│   ├── validation/        # Input validation
│   └── utils/             # Utilities (logging, errors)
├── docker/
│   ├── Dockerfile         # Multi-stage build
│   └── docker-bake.hcl    # Multi-platform config
├── tests/                 # Test suite
└── specs/                 # Design documents
```

## Development

### Running Tests

```bash
npm test                  # All tests
npm run test:unit         # Unit tests only
npm run test:integration  # Integration tests only
```

### Code Quality

```bash
npm run lint              # Check code style
npm run lint:fix          # Fix code style issues
npm run format            # Format with Prettier
npm run format:check      # Check formatting
```

### Building Docker Images

```bash
# Build for all platforms
npm run docker:build

# Or use buildx directly
docker buildx bake -f docker/docker-bake.hcl

# Build for specific platform
docker buildx bake -f docker/docker-bake.hcl amd64
docker buildx bake -f docker/docker-bake.hcl arm64
```

## Troubleshooting

### Server Won't Start

**Problem:** Server exits immediately after starting

**Solution:**
1. Check Valkey is running: `docker-compose ps valkey`
2. Verify connection: `docker-compose logs valkey`
3. Check environment variables: `cat .env`

### Connection Refused

**Problem:** `ECONNREFUSED` error connecting to Valkey

**Solution:**
1. Ensure Valkey service is healthy: `docker-compose ps`
2. Check network connectivity: `docker network ls`
3. Verify `VALKEY_HOST` matches service name in docker-compose

### Session Expired Errors

**Problem:** `Session expired` errors during testing

**Solution:**
1. Increase `MCP_SESSION_TIMEOUT` in `.env`
2. Ensure consistent session ID usage
3. Check system time synchronization

### PNR Not Found

**Problem:** `Booking not found` when retrieving by PNR

**Solution:**
1. Verify PNR format: `TEST-XXXXXX`
2. Confirm session ID matches booking session
3. Check Valkey data persistence: `docker-compose logs valkey`

## Performance

- **Search Response Time**: < 100ms (mock data generation)
- **Booking Creation**: < 200ms (Valkey write)
- **Concurrent Sessions**: 50+ simultaneous MCP connections
- **Session Capacity**: 1000+ bookings per session
- **Memory Footprint**: ~50MB (Node.js + dependencies)

## Contributing

This is a mock server for testing purposes. Contributions welcome for:

- Additional airline/airport data
- Enhanced mock data realism
- Performance optimizations
- Bug fixes

## License

MIT License - See LICENSE file for details

## Support

For issues and questions:
- GitHub Issues: <repository-url>/issues
- Documentation: See `/specs` directory for detailed design docs

---

**Remember**: This is a MOCK server. All bookings are simulated. Never use in production systems requiring real GDS connectivity.