asyncio — Asynchronous异步 I/O

---

Hello World!

import asyncio
async def main():
    print('Hello ...')
    await asyncio.sleep(1)
    print('... World!')

# Python 3.7+
asyncio.run(main())

asyncio is a library to write concurrent code using the async/await syntax.是一个使用异步/等待语法编写并发代码的库。

asyncio is used as a foundation for multiple Python asynchronous frameworks that provide high-performance network and web-servers, database connection libraries, distributed task queues, etc.用作提供高性能网络和web服务器、数据库连接库、分布式任务队列等的多个Python异步框架的基础。

asyncio is often a perfect fit for IO-bound and high-level structured network code.通常非常适合IO绑定和高级结构化网络代码。

asyncio provides a set of high-level APIs to:提供一组高级API，用于：

• run Python coroutines concurrently and have full control over their execution;并发运行Python协程，并完全控制其执行；

• perform network IO and IPC;实施网络IO和IPC；

• control subprocesses;控制子进程；

• distribute tasks via queues;通过队列分发任务；

• synchronize concurrent code;同步并发代码；

Additionally, there are low-level APIs for library and framework developers to:此外，库和框架开发人员还可以使用低级API：

• create and manage event loops, which provide asynchronous APIs for networking, running subprocesses, handling OS signals, etc;创建和管理事件循环，为networking、运行subprocesses、处理OS signals等提供异步API；

• implement efficient protocols using transports;使用传输实现高效协议；

• bridge callback-based libraries and code with async/await syntax.使用异步/等待语法桥接基于回调的库和代码。

Reference参考

High-level APIs高级API

• Coroutines and Tasks协同程序和任务
• Streams流
• Synchronization Primitives同步原语
• Subprocesses子进程
• Queues队列
• Exceptions异常

Low-level APIs低级API

• Event Loop事件循环
• Futures期货
• Transports and Protocols传输和协议
• Policies策略
• Platform Support平台支撑

Guides and Tutorials指南和教程

• High-level API Index高级API索引
• Low-level API Index低级别API索引
• Developing with asyncio使用asyncio开发

Note

The source code for asyncio can be found in Lib/asyncio/.asyncio的源代码可以在Lib/asyncio/中找到。