Parallel Web Server

A high-performance multithreaded HTTP web server written in Rust, built for handling multiple concurrent connections efficiently using a thread pool architecture.

Features

• Multithreaded Architecture: Uses a thread pool with worker threads to handle multiple concurrent client connections
• Graceful Shutdown: Supports Ctrl-C interruption with proper cleanup
• Request Statistics: Tracks and reports statistics about handled requests
• Response Caching: Implements caching mechanism for improved performance
• Static File Serving: Serves HTML files with appropriate responses
• Error Handling: Returns proper HTTP 404 responses for not found resources

Project Structure

src/
├── main.rs           # Entry point - sets up thread pool, listener, and reporters
├── lib.rs            # Library exports
├── thread_pool.rs    # Thread pool implementation for managing worker threads
├── tcp.rs            # TCP listener with cancellation support
├── handler.rs        # HTTP request handler
├── cache.rs          # Caching mechanism for responses
└── statistic.rs      # Statistics collection and reporting

Prerequisites

• Rust 1.70 or later

Building

cargo build

Running

cargo run

The server will start listening on localhost:7878 and print:

Run `curl http://localhost:7878/KEY` to query the server with KEY

Usage

Testing with curl

# Request a simple response
curl http://localhost:7878/hello

# Request with sleep delay
curl http://localhost:7878/sleep

# Request a non-existent resource (404)
curl http://localhost:7878/notfound

Browser Access

Open your browser and navigate to:

• http://localhost:7878/hello - Hello page
• http://localhost:7878/sleep - Sleep test page
• http://localhost:7878/notfound - Not found page

Graceful Shutdown

Press Ctrl-C to gracefully shut down the server. The server will:

1. Stop accepting new connections
2. Wait for all ongoing requests to complete
3. Print final statistics
4. Exit cleanly

Architecture

Thread Pool

The server uses a custom thread pool to manage worker threads. The thread pool:

• Pre-allocates a fixed number of worker threads
• Distributes incoming jobs across available workers
• Ensures graceful shutdown by joining all worker threads

Connection Handling

1. Listener Thread: Accepts incoming TCP connections
2. Worker Threads: Handle individual HTTP requests
3. Reporter Thread: Aggregates and reports statistics from all workers

Statistics

The server tracks:

• Number of requests handled
• Response types and status codes
• Request metadata and timing information

Dependencies

• crossbeam (0.8.4): Provides efficient multi-threading primitives
• ctrlc (3.4): Handles Ctrl-C signals for graceful shutdown
• regex (1.11.1): Regular expression support for request parsing

Configuration

Default settings:

• Address: localhost:7878
• Thread Pool Size: 7 worker threads
• HTML Files: hello.html, notfound.html, sleep.html

Future Enhancements

• Configurable port and address
• Adjustable thread pool size
• Additional HTTP methods support (POST, PUT, DELETE)
• HTTPS/TLS support
• Logging framework integration
• Configuration file support

License

This project is educational and provided as-is.