Eventlet Documentation¶
Warning¶
New usages of eventlet are now heavily discouraged! Please read the following.
Eventlet was created almost 18 years ago, at a time where async features were absent from the CPython stdlib. With time eventlet evolved and CPython too, but since several years the maintenance activity of eventlet decreased leading to a growing gap between eventlet and the CPython implementation.
This gap is now too high and can lead you to unexpected side effects and bugs in your applications.
Eventlet now follows a new maintenance policy. Only maintenance for stability and bug fixing will be provided. No new features will be accepted, except those related to the asyncio migration. Usages in new projects are discouraged. Our goal is to plan the retirement of eventlet and to give you ways to move away from eventlet.
If you are looking for a library to manage async network programming, and if you do not yet use eventlet, then, we encourage you to use asyncio, which is the official async library of the CPython stdlib.
If you already use eventlet, we hope to enable migration to asyncio for some use cases; see Migrating off of Eventlet. Only new features related to the migration solution will be accepted.
If you have questions concerning maintenance goals or concerning the migration do not hesitate to open a new issue, we will be happy to answer them.
Installation¶
The easiest way to get Eventlet is to use pip:
pip install -U eventlet
To install latest development version once:
pip install -U https://github.com/eventlet/eventlet/archive/master.zip
Usage¶
Code talks! This is a simple web crawler that fetches a bunch of urls concurrently:
urls = [
"http://www.google.com/intl/en_ALL/images/logo.gif",
"http://python.org/images/python-logo.gif",
"http://us.i1.yimg.com/us.yimg.com/i/ww/beta/y3.gif",
]
import eventlet
from eventlet.green.urllib.request import urlopen
def fetch(url):
return urlopen(url).read()
pool = eventlet.GreenPool()
for body in pool.imap(fetch, urls):
print("got body", len(body))
Supported Python Versions¶
Currently supporting CPython 3.7+.
Concepts & References¶
- Asyncio in Eventlet
- Basic Usage
- Primary API
- Design Patterns
- Greening The World
- Examples
- Using SSL With Eventlet
- Threads
- Zeromq
- Understanding Eventlet Hubs
- Environment Variables
- Module Reference
asyncio- Integration withasynciobackdoor– Python interactive interpreter within a running processcorolocal– Coroutine local storagedagpool– Dependency-Driven Greenthreads- Module Contents
debug– Debugging tools for Eventletdb_pool– DBAPI 2 database connection poolingevent– Cross-greenthread primitivegreenpool– Green Thread Poolsgreenthread– Green Thread Implementationpools- Generic pools of resourcesqueue– Queue classsemaphore– Semaphore classestimeout– Universal Timeoutswebsocket– Websocket Serverwsgi– WSGI servereventlet.green.zmq– ØMQ support
Want to contribute?¶
License¶
Eventlet is made available under the terms of the open source MIT license
Changelog¶
For further details about released versions of Eventlet please take a look at the Changelog.