# MCP MySQL Server

A MCP MySQL server with DDL support, permission control and operation logs.

## Version History

### v2.0.2 (Latest)
- ✅ **Configuration File Support**: Added JSON configuration file support with `--config` parameter
- ✅ **Command Line Arguments**: Added `--help` and `--config` command line options
- ✅ **Backward Compatibility**: Maintained environment variable support as fallback
- ✅ **Enhanced Documentation**: Updated README with configuration examples and usage instructions

### v2.0.1
- ✅ **DDL SQL Logging**: Added dedicated DDL SQL operation logging to `ddl.sql` file
- ✅ **Success-Only Logging**: Only successful DDL operations are recorded to the SQL file
- ✅ **Timestamped Entries**: Each DDL operation includes precise timestamp comments
- ✅ **Auto-Formatting**: SQL statements are automatically formatted with semicolon endings
- ✅ **New Tool**: Added `get_ddl_sql_logs` tool for querying DDL operation history
- ✅ **Enhanced Logging**: Improved logging configuration with separate DDL log file support

### v2.0.0
- ✅ Initial release with DDL support
- ✅ Permission control system
- ✅ Operation logging
- ✅ Connection pool management

## Features

- ✅ SQL query execution (DDL and DML)
- ✅ Database information retrieval
- ✅ Operation logging
- ✅ Connection pool management
- ✅ Auto-reconnection mechanism
- ✅ Health checks
- ✅ Error handling and recovery

## Installation

### Global Installation (Recommended)
```bash
npm install -g @bobliu1996/mcp-server-mysql
```

### Local Installation
```bash
npm install @bobliu1996/mcp-server-mysql
```

### From Source
```bash
git clone https://github.com/liliangshan/mcp-server-mysql.git
cd mcp-server-mysql
npm install
```

## Configuration

### Configuration File

The server now uses JSON configuration files and supports the `--config` parameter to specify the configuration file path.

#### Configuration File Structure

```json
{
  "mysql": {
    "host": "localhost",
    "port": 3306,
    "user": "root",
    "password": "",
    "database": ""
  },
  "permissions": {
    "allowDDL": false,
    "allowDrop": false,
    "allowDelete": false
  },
  "logging": {
    "logDir": "./logs",
    "logFile": "mcp-mysql.log",
    "ddlLogFile": "ddl.sql"
  }
}
```

#### Configuration Parameters

| Parameter | Description | Default |
|-----------|-------------|---------|
| `mysql.host` | MySQL server address | `localhost` |
| `mysql.port` | MySQL server port | `3306` |
| `mysql.user` | MySQL username | `root` |
| `mysql.password` | MySQL password | `` |
| `mysql.database` | Default database | `` |
| `permissions.allowDDL` | Allow DDL operations | `false` |
| `permissions.allowDrop` | Allow DROP operations | `false` |
| `permissions.allowDelete` | Allow DELETE operations | `false` |
| `logging.logDir` | Log directory | `./logs` |
| `logging.logFile` | Log filename | `mcp-mysql.log` |
| `logging.ddlLogFile` | DDL log filename | `ddl.sql` |

#### Configuration Examples

**Basic Configuration (config.json):**
```json
{
  "mysql": {
    "host": "localhost",
    "port": 3306,
    "user": "root",
    "password": "your_password",
    "database": "test_db"
  },
  "permissions": {
    "allowDDL": true,
    "allowDrop": false,
    "allowDelete": true
  },
  "logging": {
    "logDir": "./logs",
    "logFile": "mcp-mysql.log",
    "ddlLogFile": "ddl.sql"
  }
}
```

## Usage

### 1. Using Default Configuration File
```bash
# Direct run with default config.json
mcp-server-mysql

# Using npx (Recommended)
npx @bobliu1996/mcp-server-mysql
```

### 2. Specify Configuration File
```bash
# Use custom configuration file
mcp-server-mysql --config /path/to/your-config.json

# Using npx
npx @bobliu1996/mcp-server-mysql --config ./my-config.json
```

### 3. Show Help
```bash
mcp-server-mysql --help
```

### 4. Direct Start (Source Installation)
```bash
# Use default configuration
npm start

# Use custom configuration
npm start -- --config ./my-config.json
```

### 5. Managed Start (Recommended for Production)
```bash
# Use default configuration
npm run start-managed

# Use custom configuration
npm run start-managed -- --config ./prod-config.json
```

Managed start provides:
- Auto-restart (up to 10 times)
- Error recovery
- Process management
- Logging

### 6. Development Mode
```bash
npm run dev
```

## Editor Integration

### Cursor Editor Configuration

1. Create `.cursor/mcp.json` file in your project root:

**Using Configuration File (Recommended):**
```json
{
  "mcpServers": {
    "mysql": {
      "command": "npx",
      "args": ["@bobliu1996/mcp-server-mysql", "--config", "./config.json"]
    }
  }
}
```

**Multiple Instances Configuration (Support running multiple servers simultaneously):**
```json
{
  "mcpServers": {
    "mysql-dev": {
      "command": "npx",
      "args": ["@bobliu1996/mcp-server-mysql", "--config", "./config-dev.json"]
    },
    "mysql-prod": {
      "command": "npx",
      "args": ["@bobliu1996/mcp-server-mysql", "--config", "./config-prod.json"]
    }
  }
}
```

**Tool Name Isolation**: Each server instance automatically adds an instance prefix to tool names:

- **Development Instance**: `dev_sql_query`, `dev_get_database_info`, etc.
- **Production Instance**: `prod_sql_query`, `prod_get_database_info`, etc.

**Using Environment Variables (Backward Compatible):**
```json
{
  "mcpServers": {
    "mysql": {
      "command": "npx",
      "args": ["@bobliu1996/mcp-server-mysql"],
      "env": {
        "MYSQL_HOST": "your_host",
        "MYSQL_PORT": "3306",
        "MYSQL_USER": "your_user",
        "MYSQL_PASSWORD": "your_password",
        "MYSQL_DATABASE": "your_database",
        "ALLOW_DDL": "false",
        "ALLOW_DROP": "false",
        "ALLOW_DELETE": "false"
      }
    }
  }
}
```

### VS Code Configuration

1. Install the MCP extension for VS Code
2. Create `.vscode/settings.json` file:

**Using Configuration File (Recommended):**
```json
{
  "mcp.servers": {
    "mysql": {
      "command": "npx",
      "args": ["@bobliu1996/mcp-server-mysql", "--config", "./config.json"]
    }
  }
}
```

**Using Environment Variables (Backward Compatible):**
```json
{
  "mcp.servers": {
    "mysql": {
      "command": "npx",
      "args": ["@bobliu1996/mcp-server-mysql"],
      "env": {
        "MYSQL_HOST": "your_host",
        "MYSQL_PORT": "3306",
        "MYSQL_USER": "your_user",
        "MYSQL_PASSWORD": "your_password",
        "MYSQL_DATABASE": "your_database",
        "ALLOW_DDL": "false",
        "ALLOW_DROP": "false",
        "ALLOW_DELETE": "false"
      }
    }
  }
}
```

### As MCP Server

The server communicates with MCP clients via stdin/stdout after startup:

```json
{"jsonrpc": "2.0", "id": 1, "method": "initialize", "params": {"protocolVersion": "2025-06-18"}}
```

### Available Tools

1. **sql_query**: Execute SQL queries
   ```json
   {
     "jsonrpc": "2.0",
     "id": 2,
     "method": "tools/call",
     "params": {
       "name": "sql_query",
       "arguments": {
         "sql": "SELECT * FROM users LIMIT 10"
       }
     }
   }
   ```

2. **get_database_info**: Get database information
   ```json
   {
     "jsonrpc": "2.0",
     "id": 3,
     "method": "tools/call",
     "params": {
       "name": "get_database_info",
       "arguments": {}
     }
   }
   ```

3. **get_operation_logs**: Get operation logs
   ```json
   {
     "jsonrpc": "2.0",
     "id": 4,
     "method": "tools/call",
     "params": {
       "name": "get_operation_logs",
       "arguments": {
         "limit": 50,
         "offset": 0
       }
     }
   }
   ```

4. **get_ddl_sql_logs**: Get DDL SQL operation logs (v2.0.1+)
   ```json
   {
     "jsonrpc": "2.0",
     "id": 5,
     "method": "tools/call",
     "params": {
       "name": "get_ddl_sql_logs",
       "arguments": {
         "limit": 50,
         "offset": 0
       }
     }
   }
   ```

5. **check_permissions**: Check database permissions
   ```json
   {
     "jsonrpc": "2.0",
     "id": 6,
     "method": "tools/call",
     "params": {
       "name": "check_permissions",
       "arguments": {}
     }
   }
   ```

## Connection Pool Features

- **Auto-creation**: Automatically creates connection pool on `notifications/initialized`
- **Health checks**: Checks connection pool status every 5 minutes
- **Auto-reconnection**: Automatically recreates connection pool when it fails
- **Connection reuse**: Uses connection pool for better performance
- **Graceful shutdown**: Properly releases connections when server shuts down

## Logging

### General Logs
Log file location: `./logs/mcp-mysql.log`

Logged content:
- All requests and responses
- SQL operation records
- Error messages
- Connection pool status changes

### DDL SQL Logs (v2.0.1+)
DDL log file location: `./logs/ddl.sql`

Features:
- **Success-Only Recording**: Only successful DDL operations are recorded
- **Timestamped Entries**: Each operation includes precise timestamp comments
- **Auto-Formatting**: SQL statements are automatically formatted with semicolon endings
- **Executable Format**: Can be directly executed to recreate database structure

Example DDL log format:
```sql
# 2024-01-15 14:23:45
CREATE TABLE users (id INT PRIMARY KEY, name VARCHAR(100));
# 2024-01-15 14:24:12
ALTER TABLE users ADD COLUMN email VARCHAR(255);
# 2024-01-15 14:25:33
CREATE INDEX idx_email ON users(email);
```

#### DDL Logging Benefits

**🔄 Database Synchronization**
- **Production Sync**: Easily synchronize database schema changes from development to production environments
- **Multi-Environment Deployment**: Apply the same DDL changes across staging, testing, and production databases
- **Rollback Support**: Maintain a complete history of schema changes for easy rollback operations

**📋 Development Workflow**
- **Schema Versioning**: Track database evolution with timestamped change history
- **Team Collaboration**: Share database structure changes with team members through executable SQL files
- **Code Review**: Review database changes alongside application code changes

**🛡️ Operational Excellence**
- **Audit Trail**: Maintain comprehensive audit logs of all database structure modifications
- **Compliance**: Meet regulatory requirements for database change tracking
- **Disaster Recovery**: Quickly rebuild database structure from DDL logs in case of data loss

**⚡ Performance & Reliability**
- **Clean Execution**: Only successful operations are recorded, ensuring reliable script execution
- **Error Prevention**: Failed operations are excluded, preventing script execution errors
- **Automated Formatting**: Consistent SQL formatting reduces manual errors and improves readability

## Error Handling

- Individual request errors don't affect the entire server
- Connection pool errors are automatically recovered
- Process exceptions are automatically restarted (managed mode)

## Environment Variables

| Variable | Default | Description |
|----------|---------|-------------|
| MYSQL_HOST | localhost | MySQL host address |
| MYSQL_PORT | 3306 | MySQL port |
| MYSQL_USER | root | MySQL username |
| MYSQL_PASSWORD | | MySQL password |
| MYSQL_DATABASE | | Database name |
| ALLOW_DDL | false | Whether to allow DDL operations (CREATE, ALTER, TRUNCATE, RENAME, COMMENT). Set to 'true' to enable |
| ALLOW_DROP | false | Whether to allow DROP operations. Set to 'true' to enable |
| ALLOW_DELETE | false | Whether to allow DELETE operations. Set to 'true' to enable |
| MCP_LOG_DIR | ./logs | Log directory |
| MCP_LOG_FILE | mcp-mysql.log | Log filename |
| MCP_DDL_LOG_FILE | ddl.sql | DDL SQL log filename (v2.0.1+) |

## Development

### Project Structure
```
mcpmysql/
├── src/
│   └── server-final.js    # Main server file
├── start-server.js        # Managed startup script
├── package.json
└── README.md
```

### Testing
```bash
npm test
```

## Quick Start

### 1. Install Package
```bash
npm install -g @bobliu1996/mcp-server-mysql
```

### 2. Configure Environment Variables
```bash
export MYSQL_HOST=localhost
export MYSQL_PORT=3306
export MYSQL_USER=root
export MYSQL_PASSWORD=your_password
export MYSQL_DATABASE=your_database
export ALLOW_DDL=false
export ALLOW_DROP=false
export ALLOW_DELETE=false
```

**Permission Control Examples:**
```bash
# Default: Disable all destructive operations (safe mode)
export ALLOW_DDL=false
export ALLOW_DROP=false
export ALLOW_DELETE=false

# Allow DDL but disable DROP and DELETE
export ALLOW_DDL=true
export ALLOW_DROP=false
export ALLOW_DELETE=false

# Allow everything except DELETE
export ALLOW_DDL=true
export ALLOW_DROP=true
export ALLOW_DELETE=false

# Enable all operations (use with caution)
export ALLOW_DDL=true
export ALLOW_DROP=true
export ALLOW_DELETE=true
```

### 3. Run Server
```bash
mcp-server-mysql
```

## License

MIT