twisted/twisted
Twisted
Twisted is an event-driven networking engine for Python that provides a framework for building asynchronous network applications. At its core, it uses a reactor-based event loop to drive all input and output, dispatching callbacks in a single thread without blocking. The library implements a deferred promise chain for composing asynchronous logic, along with a protocol and factory pattern that separates connection state management from protocol handling, enabling reusable handlers for different network protocols.
The framework supports multiple event loops across platforms, including select, poll, epoll, kqueue, and IOCP, all behind a uniform reactor adaptation interface. Its transport abstraction layer decouples data transmission from protocol implementations, allowing TCP, UDP, SSL, and Unix sockets to be used interchangeably. A plugin-based service architecture enables modular extension of server capabilities, while inline callback scheduling allows delayed or repeated callbacks to run directly on the reactor without threads.
Twisted provides implementations for a wide range of network protocols, including HTTP clients and servers with WSGI support, DNS resolution and server creation, SSH and Telnet for remote shell access and file transfer, email handling via SMTP, POP3, and IMAP, and instant messaging through IRC and XMPP. The library also includes tools for testing asynchronous code that integrates with the event loop and deferred patterns.
Features
- Event-Driven Networking - Core event-driven networking engine using a reactor pattern and deferred callbacks for async I/O.
- Reactor Pattern Event Loops - Drives all asynchronous I/O through a reactor-based event loop that polls and dispatches callbacks.
- Asynchronous Event Loops - Core reactor-based event loop drives all asynchronous I/O operations.
- HTTP Clients and Servers - Ships HTTP client and server implementations with WSGI support for building web applications.
- Asynchronous Web Servers - Ships a full asynchronous HTTP server with WSGI support for hosting web applications.
- Deferred Promise Objects - Implements deferred promise objects for composing asynchronous callbacks and error handling chains.
- Platform Event Loop Adapters - Switches between select, poll, epoll, kqueue, and IOCP event loops transparently.
- Asynchronous Network Clients - Constructs clients that send and receive data over network protocols without blocking on I/O.
- Network Protocol Implementations - Provides a toolkit for implementing custom and standard network protocols with built-in support.
- Custom Protocol Servers - Enables building custom protocol servers by handling connections and parsing messages asynchronously.
- Platform Event Loop Pumps - Runs network code on select, poll, epoll, kqueue, IOCP, or GUI event loops for cross-platform compatibility.
- Transport Abstraction Layers - Decouples data transmission from protocol implementations, supporting TCP, UDP, SSL, and Unix sockets.
- Async I/O Runtimes - Provides a Python async I/O framework with a reactor pattern for non-blocking network operations.
- Concurrent Connection Handling - Manages many simultaneous network connections using an event-driven, non-blocking I/O model.
- SSH Server Hosting - Provides SSH server and client implementations for secure remote shell access and file transfer.
- SSH and Telnet Clients - Provides SSH and Telnet client and server implementations for secure remote shell access.
- Protocol and Factory Patterns - Implements the protocol and factory pattern to separate connection state from protocol logic.
- Platform Event Loop Adapters - Provides a uniform adapter interface over select, poll, epoll, kqueue, and IOCP event loops.
- Inline Callback Schedulers - Provides inline callback scheduling on the reactor for delayed and repeated tasks without threads.
- Asynchronous Network Programming - Provides a framework for building asynchronous network applications with custom protocol handlers.
- Multi-Protocol Networking Libraries - Supports multiple network protocols including IRC, XMPP, SMTP, POP3, IMAP, SSH, and Telnet.
- Asynchronous Web Servers - Serves web applications by routing HTTP requests to application logic asynchronously.
- IRC and XMPP Protocol Implementations - Provides IRC and XMPP protocol implementations for building messaging applications.
- IRC and XMPP Libraries - Implements IRC and XMPP client and server protocols for building chat applications.
- Remote Command Execution - Executes shell commands on remote hosts via SSH connections.
- Asynchronous HTTP Servers - Ships an asynchronous HTTP server with WSGI support for non-blocking web application hosting.
- DNS Record Resolvers - Resolves domain names and serves as a custom DNS server for domain name resolution.
- DNS Resolution - Ships DNS resolution and server creation tools for domain name lookup and custom DNS services.
- Hostname Resolvers - Provides DNS client capabilities for hostname resolution and reverse lookups.
- Instant Messaging Services - Implements IRC and XMPP protocols for real-time instant messaging.
- IMAP, POP3, and SMTP Implementations - Provides client and server implementations for SMTP, POP3, and IMAP email protocols.
- IRC and XMPP Chat Clients - Ships IRC and XMPP client implementations for connecting to chat networks.
- Real-Time Messaging - Supports IRC and XMPP protocols for building real-time chat and instant messaging applications.
- Email Sending and Retrieval - Implements SMTP, POP3, and IMAP protocols for sending, receiving, and managing email.
- Authenticated SSH Connections - Implements SSH client connections with authentication and command execution.
- SFTP File Transfers - Implements SFTP file transfer capabilities over encrypted SSH connections for remote file management.
- DNS Server Creators - Includes tools for creating custom DNS servers alongside client-side resolution.
- SSH and Telnet Server Emulators - Provides SSHv2 and Telnet server implementations for hosting remote access services.
- SSH and Telnet Server Implementations - Provides SSHv2 and Telnet server implementations for remote shell access.
- Plugin-Based Architectures - Ships a plugin-based service architecture for modular extension of server capabilities.
- SSH and Telnet Remote Shells - Provides SSH and Telnet server and client implementations for remote shell sessions.
- Concurrent Code Testing - Runs unit tests designed for event-driven code that integrates with reactor and deferred patterns.
- Async - Provides tools for running unit tests on asynchronous code that integrates with the event loop.
- Asynchronous Programming - Implements an event-driven networking engine.
