Async HTTP Server (C++17)

A high-performance asynchronous HTTP server built with Reactor + Thread Pool architecture, implemented in native C++17. Supports 10K+ concurrent connections with full HTTP/1.1 protocol implementation.

Features

Architectural

• Reactor Pattern based on Linux epoll (edge-triggered)
• Thread Pool for CPU-intensive tasks (HTTP parsing, business logic)
• Zero-copy notifications via pipe for inter-thread communication
• Lock-free structures for concurrent metadata access

Networking

• Full HTTP/1.1 support (keep-alive, pipeline, chunked encoding)
• Connection management with timeouts and request limits
• Graceful shutdown with active connection completion
• Non-blocking I/O at all processing stages

Architecture

Overview

┌─────────────────────────────────────────────────────┐
│                    Main Thread (Reactor)            │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐ │
│  │   epoll     │  │   pipe      │  │   timer     │ │
│  │   (I/O)     │◄─┤(notifications)│  │(timeouts)  │ │
│  └──────┬──────┘  └─────────────┘  └─────────────┘ │
│         │                                          │
│         ▼                                          │
│  ┌─────────────┐       ┌─────────────────────┐    │
│  │ Connection  │──────►│   Thread Pool       │    │
│  │   State     │       │  (Worker Threads)   │    │
│  │   Machine   │◄──────│  • HTTP Parsing     │    │
│  └─────────────┘       │  • Business Logic   │    │
│                        └─────────────────────┘    │
└─────────────────────────────────────────────────────┘

Quick Start

Prerequisites

• Linux or WSL 2 (Ubuntu 20.04+)
• CMake 3.15+
• GCC 9+ or Clang 10+
• Git

Install Dependencies (Ubuntu/WSL)

sudo apt update
sudo apt install -y build-essential cmake git

Clone and Build

# Clone repository
git clone https://github.com/yourusername/async-http-server.git
cd async-http-server

# Create build directory
mkdir build && cd build

# Configure CMake
cmake .. -DCMAKE_BUILD_TYPE=Release

# Build project
make -j$(nproc)

# Run server
./server

Server will start on localhost:8080. Test it:

curl http://localhost:8080/
# Output: Processed in thread pool. Path: /

HTTP Features

Supported Methods

• ✅ GET - Retrieve resources
• ✅ HEAD - Resource headers
• ⏳ POST - Partial support
• ❌ PUT, DELETE, PATCH - In development

# Supported headers
Connection: keep-alive
Keep-Alive: timeout=5, max=100
Content-Length: 123
Host: example.com
User-Agent: Custom-Client/1.0

Keep-Alive Parameters

Parameter	Default	Description
timeout	30 seconds	Time to wait for next request
max	100 requests	Maximum requests per connection
Connection	keep-alive	Connection state management