Go Chat Server

A production-ready, real-time chat server built with Go, demonstrating concurrent programming, WebSocket communication, and clean architecture patterns.

Table of Contents

• Overview
• Features
• Architecture
• Requirements
• Installation
• Configuration
• Running the Server
• Usage
• API Documentation
• Testing
• Deployment
• Troubleshooting
• License

Overview

This project is a real-time chat server that showcases Go's strengths in concurrent programming and network communication. It implements a WebSocket-based messaging system with multiple chat rooms, user presence tracking, and message history persistence.

The application demonstrates:

• Goroutine management and channel-based communication
• WebSocket protocol implementation
• Real-time message broadcasting
• Clean architecture with separation of concerns
• Production-ready error handling and logging

Features

Core Functionality

• Real-time messaging with WebSocket support
• Multiple chat rooms (general, technology, random)
• User presence indicators
• Message history (last 100 messages per room)
• Persistent message storage in memory

User Features

• Custom username on join
• Room switching with /join command
• User list display with /users command
• Help system with /help command
• Current room display with /room command

Technical Features

• Concurrent client handling with goroutines
• Graceful shutdown handling
• Cross-origin resource sharing (CORS) enabled
• Mobile-responsive web interface
• Network-wide accessibility

Architecture

┌─────────────────────────────────────────────────────────────┐ │ Client Browser │ │ (WebSocket Connection) │ └──────────────────────────┬──────────────────────────────────┘ │ ▼ ┌─────────────────────────────────────────────────────────────┐ │ Go Server │ │ ┌─────────────┐ ┌─────────────┐ ┌─────────────────────┐ │ │ │ Hub │ │ Client │ │ Message Protocol │ │ │ │ - Registry │ │ - Read Pump │ │ - Chat Messages │ │ │ │ - Rooms │ │ - Write Pump│ │ - System Messages │ │ │ │ - Broadcast │ │ - Commands │ │ - Command Handling │ │ │ └─────────────┘ └─────────────┘ └─────────────────────┘ │ └─────────────────────────────────────────────────────────────┘ │ ▼ ┌─────────────────────────────────────────────────────────────┐ │ In-Memory Storage │ │ (Message History per Room) │ └─────────────────────────────────────────────────────────────┘

Design Patterns Used

• Hub Pattern: Centralized client and room management
• Observer Pattern: Message broadcasting to multiple clients
• Command Pattern: Chat command processing
• Factory Pattern: Message creation and validation

Requirements

Tool	Version	Verification Command
Go	1.21+	go version
Git	Latest	git --version
Make	3.81+	make --version