🚀 CExpress

Because C deserves frameworks as simple as Express.js

A lightweight HTTP server framework for C that brings the simplicity of Express.js to the power and performance of C.

CExpress is a minimal, high-performance HTTP server framework written in C that provides Express.js-like functionality for building web applications and APIs. Perfect for microservices, APIs, static file serving, and rapid prototyping without the overhead of larger frameworks.

📖 Full documentation available at: CExpress Docs

📚 Table of Contents

• Overview
• Features
• Installation
• Quick Start
• Examples
• API Reference
• Architecture
• Performance
• Contributing

📖 Overview

CExpress brings the familiar Express.js patterns to C development:

• Rapid Prototyping: Build and test instantly
• Simple routing: GET, POST, PUT, DELETE
• Handler-based architecture: Modular, clean code
• Static file serving: Out of the box
• JSON API support: Built-in response formatting
• Cross-platform: Linux and macOS

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✨ Features

🎯 Core Features

• Lightweight: Minimal memory footprint and dependencies
• Fast: Built on efficient C socket programming
• Simple: Express.js-inspired API design
• Flexible: Support for various use cases and patterns

🔧 Technical Features

• HTTP/1.1 compliant request/response handling
• Dynamic routing with method and path matching
• Memory management with automatic cleanup
• Error handling with proper HTTP status codes
• Signal handling for graceful shutdown
• Concurrent client support with select() multiplexing

🌐 Supported Use Cases

• REST APIs and microservices
• Static file hosting
• Web application backends
• Rapid development servers
• Prototyping and testing
• Embedded web interfaces

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Installation

CExpress can be installed as a shared C library in two ways:

1. Install from GitHub (macOS & Linux)

Prerequisites

• GCC or Clang compiler
• Make utility

Install

git clone https://github.com/Karl-Michaud/CExpress.git
cd CExpress
make install

This will:

• Copy the shared library (libCExpress.dylib on macOS, or libCExpress.so on Linux) to /usr/local/lib/
• Copy the header files to /usr/local/include/CExpress/

Uninstall

To remove CExpress, run:

make uninstall

Notes

• To install to a different location, set the PREFIX variable:

  make install PREFIX=/custom/path

• For Linux, the shared library extension is .so; for macOS, it is .dylib.

2. Install via Homebrew (macOS)

Install

brew tap Karl-Michaud/cexpress
brew install cexpress

(Optional) Verify installation:

gcc -o test test.c -lCExpress
./test

Uninstall

brew uninstall cexpress

(Optional) Remove the tap and clear cached downloads:

brew untap Karl-Michaud/cexpress
brew cleanup

This will remove the CExpress library and headers installed by Homebrew.

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🚀 Quick Start

#include <CExpress/server.h>
#include <stdio.h>
#include <stdlib.h>

char *hello_handler(void) {
    char *response = malloc(50);
    strcpy(response, "Hello from CExpress!");
    return response;
}

int main(void) {
    // Initialize server
    Server *server = server_init(8080, 10, 5, DEV);
    if (!server) {
        fprintf(stderr, "Failed to initialize server\n");
        return 1;
    }
    
    // Add route
    server_add_route(server, GET, "/hello", hello_handler);
    
    // Start server
    server_start(server);
    
    // Cleanup (automatic on shutdown)
    return 0;
}

Compile and Run

gcc -o server main.c -lCExpress
./server

Test with:

curl http://localhost:8080/hello

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📝 Examples

Found in examples/

1. Hello World → minimal GET route
2. JSON API → Multi-method API with JSON responses, error handling, and data management.
3. Static Files → serve HTML, CSS, JS
4. REST API → Full CRUD operations with proper REST patterns and status codes.

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📖 API Reference

Server Management

// Initialize server
Server *server_init(int port, int max_clients, int backlog, Mode mode);

// Start server (blocks until shutdown)
int server_start(Server *server);

// Clean up resources
void server_free(Server *server);

Routing

// Add route
int server_add_route(Server *server, method_t method, path_t path, HandlerFunc handler);

// Remove route
int server_remove_route(Server *server, method_t method, path_t path);

Handler Functions

// Handler function signature
typedef char *(*HandlerFunc)(void);

// Example handler
char *my_handler(void) {
    char *response = malloc(100);
    strcpy(response, "Hello World!");
    return response;
}

HTTP Methods

typedef enum {GET, POST, PUT, DELETE, FAIL} method_t;

Server Modes

typedef enum {DEV, PROD} Mode;
// DEV  - localhost only (127.0.0.1)
// PROD - all interfaces (0.0.0.0)

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Architecture

CExpress follows a modular architecture:

┌─────────────────┐
│   Public API    │  ← server.h
├─────────────────┤
│   Server Core   │  ← server.c
├─────────────────┤
│   Routing       │  ← routers.c/h
├─────────────────┤
│   Handlers      │  ← handlers.c/h
├─────────────────┤
│   Utilities     │  ← utils.c/h
└─────────────────┘

Request Flow

1. Client Request → Server Socket
2. Accept Connection → Client List
3. Read Data → Buffer
4. Parse Header → Extract Method/Path
5. Find Route → Router List
6. Execute Handler → Generate Response
7. Send Response → Client
8. Cleanup → Memory Management

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⚡ Performance

CExpress is designed for performance:

• Low Latency: Direct socket programming
• Memory Efficient: Minimal allocations and automatic cleanup
• Concurrent: Multiple client support
• Lightweight: Small binary size and memory footprint
• Rapid Prototyping: Instantly build and test web applications without the overhead of large frameworks

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🤝 Contributing

I welcome contributions! Here's how to get started:

Development Setup

1. Fork the repository & create a feature branch
2. Make your changes & add tests if applicable
3. Submit a PR 🚀

Areas for Contribution

• Additional HTTP methods
• Middleware support
• WebSocket support
• Enhanced error handling
• Performance optimizations
• Additional examples

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Made by Karl-Alexandre Michaud

Because C deserves frameworks as simple as Express.js