Webserv

A complete HTTP/1.1 server implemented in C++98 as part of the 42 school Webserv project.

Description

Webserv is an asynchronous non-blocking web server capable of handling multiple simultaneous clients through an event-driven architecture based on poll(). It implements the main features of a modern HTTP server including virtual hosting, CGI execution, and request handling.

Features

HTTP/1.1 Protocol

• Supported methods: GET, POST, DELETE
• Chunked transfer encoding
• Timeout management: headers, inactivity, CGI
• Complete HTTP status codes (2xx, 3xx, 4xx, 5xx)
• Standard HTTP headers with automatic MIME type detection

HTTP Methods

GET

• File serving with efficient streaming
• AutoIndex: HTML generation of directory listings
• Automatic MIME type detection

POST

• File upload
• Automatic unique filename generation
• Write permission verification
• Request body parsing with size limits

DELETE

• File/directory deletion
• Security checks for accessible paths

Common Gateway Interface (CGI)

• Process forking with pipe communication
• Standard CGI environment variables
• Configurable execution timeout (4s default)
• Complete CGI response header handling

Virtual Hosting

• Multi-server: multiple servers in one instance
• Selection by:
  • IP:Port binding
  • Hostname via Host header
• Multiple locations with path matching
• Hierarchical configuration with value inheritance

Technical Architecture

• Event-driven architecture with poll() loop
• Non-blocking I/O on all sockets
• Multiplexing: up to 100 simultaneous clients
• State management: requests and responses with state machine

Usage

Server Launch

# With default configuration
./webserv

# With custom configuration file
./webserv path/to/config.conf

Technical Architecture

Concurrency Model

The server uses an event-driven model with multiplexing:

• Main loop with poll() (1000ms timeout)
• Non-blocking I/O for all sockets
• Simultaneous handling of up to 100 clients
• Request/response states with state machine

Class Hierarchy

WebServer (Singleton)
├── VirtualHost[] (virtual servers)
│   ├── BindingInfo (IP:Port)
│   └── Location[] (locations)
└── Client[] (connected clients)
    ├── HttpRequest (parsing)
    ├── HttpResponse (generation)
    └── ARequestHandler (abstract handler)
        ├── MethodHandler (GET/POST/DELETE)
        └── CGIHandler (CGI execution)

Timeouts and Limits

Parameter	Value	Description
REQUEST_HEADERS_TIMEOUT	4s	Header read timeout
INACTIVITY_TIMEOUT	7s	Client inactivity timeout
CGI_EXECUTION_TIMEOUT	4s	CGI execution timeout
MAX_CLIENTS	100	Maximum simultaneous clients
READ_BUFFER	8192	Read buffer size
WRITE_BUFFER	8192	Write buffer size