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我想通过使用this module在Python中实现一个简单的网络套接字服务器。为了学习的目的，服务器应该以它收到的反向版本回复。例如，如果客户端发送“Hello Server”，则服务器应以“revreS olleH”响应。我的代码是基于关闭文档here创建一个Simpe Python网络套接字服务器
由于consumer()和producer()功能/协同程序的例子并没有在文档中提供的，我参加了一个刺创造他们，但想到我误解并不明显，我的东西。该代码当前返回字符串'nothing'而不是客户端发送的反向版本。
仅供参考，由于我使用的机器是Python 3.4.3，因此必须调整代码以适应该版本。这就是为什么现在你会看到更新的代码被注释掉的原因。当我学习这些东西时，也包含了很多文档。
现在，codez ...
index.py：
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#########################
# Dependencies
#########################
# asyncio
# websockets
#########################
# Modules
#########################
import asyncio
import websockets
#########################
# Functions
#########################
# async indicates an asynchronous function.
# Calling them doesn't actually run them,
# but instead a coroutine object is returned,
# which can then be passed to the event loop to be executed later on.
# Python ≥ 3.5: async def producer(reply):
@asyncio.coroutine
def producer(reply=None):
"""Sends the reply to producer_handler."""
if reply is None:
return 'nothing'
else:
return reply
# Python ≥ 3.5: async def consumer(message):
@asyncio.coroutine
def consumer(message):
"""Reverses message then sends it to the producer."""
reply = message[::-1]
#await producer(reply)
yield from producer(reply)
# async def consumer_handler(websocket):
@asyncio.coroutine
def consumer_handler(websocket):
"""Handles incoming websocket messages."""
while True:
# await calls an asynchronous function.
#message = await websocket.recv()
message = yield from websocket.recv()
# Python ≥ 3.5: await consumer(message)
yield from consumer(message)
#async def producer_handler(websocket):
@asyncio.coroutine
def producer_handler(websocket):
"""Handles outgoing websocket messages."""
while True:
#message = await producer()
message = yield from producer()
#await websocket.send(message)
yield from websocket.send(message)
#async def handler(websocket, path):
@asyncio.coroutine
def handler(websocket, path):
"""Enables reading and writing messages on the same websocket connection."""
# A Future is an object that is supposed to have a result in the future.
# ensure_future:
# schedules the execution of a coroutine object,
# wraps it in a future, then returns a Task object.
# If the argument is a Future, it is returned directly.
# Python ≥ 3.5
#consumer_task = asyncio.ensure_future(consumer_handler(websocket))
#producer_task = asyncio.ensure_future(producer_handler(websocket))
consumer_task = asyncio.async(consumer_handler(websocket))
producer_task = asyncio.async(producer_handler(websocket))
# .wait:
# wait for the Futures and coroutine objects given
# by the sequence futures to complete. Coroutines will be
# wrapped in Tasks. Returns two sets of Future: (done, pending).
#done, pending = await asyncio.wait(
done, pending = yield from asyncio.wait(
# The futures.
[consumer_task, producer_task],
# FIRST_COMPLETED: the function will return when
# any future finishes or is cancelled.
return_when=asyncio.FIRST_COMPLETED,
)
for task in pending:
task.cancel()
#########################
# Start script
#########################
def main():
# Creates a WebSocket server.
start_server = websockets.serve(handler, '127.0.0.1', 8000)
# Get the event loop for the current context.
# Run until the Future is done.
asyncio.get_event_loop().run_until_complete(start_server)
# Run until stop() is called.
asyncio.get_event_loop().run_forever()
#########################
# Script entry point.
#########################
if __name__ == '__main__':
main()
的index.html：
<!DOCTYPE html>
<html>
<head>
<title>WebSocket demo</title>
</head>
<body>
<script>
// Create the websocket.
var ws = new WebSocket("ws://127.0.0.1:8000/"),
messages = document.createElement('ul');
// Called when the websocket is opened.
ws.onopen = function(event) {
ws.send('Hello Server!');
};
// Called when a message is received from server.
ws.onmessage = function(event) {
var messages = document.getElementsByTagName('ul')[0],
message = document.createElement('li'),
content = document.createTextNode(event.data);
message.appendChild(content);
messages.appendChild(message);
};
document.body.appendChild(messages);
</script>
</body>
</html>