CData MCP Gateway

A lightweight HTTP streaming gateway that bridges CData's stdio-based MCP servers with HTTP-based MCP clients like the MCP Inspector.

Overview

This gateway enables HTTP clients to communicate with CData MCP Servers (like Salesforce, SQL Server, etc.) that use stdio transport. It handles:

• Protocol translation between HTTP streaming and stdio
• Session management for multiple concurrent clients
• Interception of unsupported MCP methods

Features

• HTTP to stdio bridge: Translates HTTP streaming requests to stdio communication
• Session management: Maintains a default shared session for all requests
• Method interception: Handles methods that CData servers don't implement (resources/list, logging/setLevel)
• Environment-based configuration: Uses .env file for configuration
• Full tool support: CData server properly returns all tools with connection name prefixes

Installation

npm install

Configuration

Create a .env file:

# Server Configuration
PORT=3000
LOG_LEVEL=info

# MCP Server Configuration
# For CData MCP Servers (Salesforce as an example)

# Windows
MCP_COMMAND=C:/Program Files/CData/CData MCP Server for Salesforce 2024/jre/bin/java.exe
MCP_ARGS=-jar,C:/Program Files/CData/CData MCP Server for Salesforce 2024/lib/cdata.mcp.salesforce.jar,salesforce_dev

# MacOS
MCP_COMMAND=/Applications/CData MCP Servers for Salesforce 2025.app/Contents/Payload/jre/Contents/Home/bin/java
MCP_ARGS=-Dfile.encoding=UTF-8,-jar,/Applications/CData MCP Servers for Salesforce 2025.app/Contents/Payload/lib/cdata.mcp.salesforce.jar,salesforce_dev

The last argument in MCP_ARGS is used as the connection name for tool prefixing.

Usage

Development

npm run dev

Production

npm run build
npm start

With MCP Inspector

# Start the gateway
npm run dev

# In another terminal, start the MCP Inspector
npx @modelcontextprotocol/inspector http://localhost:3000/mcp

Available Tools

When connected to a CData Salesforce server with connection name salesforce_dev:

• salesforce_dev_get_tables - List all available tables
• salesforce_dev_get_columns - Get column information for a table
• salesforce_dev_run_query - Execute SQL SELECT queries
• salesforce_dev_run_nonquery - Execute INSERT/UPDATE/DELETE statements
• salesforce_dev_add_row - Add a new record to a table

Architecture

MCP (HTTP) Client
         ↓
    HTTP/SSE Transport
         ↓
    MCP Gateway (this project)
         ↓
    stdio Transport
         ↓
CData MCP Server (Java process)
         ↓
    Salesforce/SQL/etc API

File Structure

src/
├── gateway.ts    # Main gateway implementation
├── index.ts      # Express server setup
└── logger.ts     # Logging configuration

License

MIT