Go-SQL-Proxy

This project implements a SQL proxy server in Golang that acts as an intermediary between a client and a MySQL server. The proxy server can handle protocol decoding and data transfer while measuring and updating metrics for monitoring purposes.

Project Structure

The project is structured as follows:

• pkg/
  • config/
    • config.go: Contains the configuration settings and loads them from environment variables.
  • logging/
    • logging.go: Handles setting up and configuring the logger using Logrus.
  • metrics/
    • metrics.go: Implements metrics collection and exposes Prometheus metrics endpoints.
  • health/
    • health.go: Handles health check endpoints for database connectivity.
  • protocol/
    • flags.go: Defines MySQL capability flags used in the protocol.
    • math.go: Contains utility functions for mathematical operations.
    • protocol.go: Implements decoding and encoding of MySQL protocol packets.
  • proxy/
    • NewConnection.go: Creates a new proxy connection to the target MySQL server.
    • NewProxy.go: Creates a new instance of the Proxy server.
    • HandleConnection.go: Manages data transfer and protocol decoding for a connection.
    • proxyHandle.go: Handles a new connection request in a goroutine.
    • transferData.go: Handles data transfer between client and server while measuring latency.
    • StartProxy.go: Starts the proxy server and accepts incoming connections.
    • EnableDecoding.go: Enables protocol decoding for the proxy.
    • handleProtocolDecoding.go: Decodes the MySQL protocol handshake.
  • models/
    • Proxy.go: Defines the structure for the proxy server configuration and state.
    • Connection.go: Represents a connection to a MySQL server.
• main.go: Main entry point of the proxy server application.

Running the Server

To start the Go-SQL-Proxy server, the main entry point is main.go. The server can be started by running this file with the necessary environment variables configured to set up the proxy settings.

To run the server, execute the following command:

go run main.go

Configuration

The proxy is configured through environment variables:

Basic Configuration

• DEBUG: Enable debug logging (default: false)
• METRICS_PORT: Port for metrics/health endpoints (default: 9090)
• BIND_ADDRESS: Proxy bind address (default: 0.0.0.0)
• BIND_PORT: Proxy listening port (default: 3306)

Database Connection

• SOURCE_DATABASE_SERVER: Target MySQL server hostname
• SOURCE_DATABASE_PORT: Target MySQL server port (default: 25060)
• SOURCE_DATABASE_USER: MySQL username
• SOURCE_DATABASE_PASSWORD: MySQL password
• SOURCE_DATABASE_NAME: Default database name

SSL/TLS Configuration

• USE_SSL: Enable SSL/TLS connection to upstream MySQL (default: false)
• SSL_SKIP_VERIFY: Skip SSL certificate verification (default: false)
• SSL_CA_FILE: Path to CA certificate file for SSL verification
• SSL_CERT_FILE: Path to client certificate file for mutual TLS
• SSL_KEY_FILE: Path to client key file for mutual TLS

Example: Connecting to PlanetScale

export SOURCE_DATABASE_SERVER=your-database.planetscale.com
export SOURCE_DATABASE_PORT=3306
export SOURCE_DATABASE_USER=your-username
export SOURCE_DATABASE_PASSWORD=your-password
export SOURCE_DATABASE_NAME=your-database
export USE_SSL=true
export SSL_SKIP_VERIFY=true

go run main.go

Note

• This implementation serves as a basic demonstration of a SQL proxy server and may require additional features for production use.
• Ensure proper configuration of database access and proxy settings before running the server in a production environment.

Feel free to explore and extend this project for your specific use case or requirements!