Question

我有一个简单的命令和控制服务器server.py（完全不安全 - 不要使用），被动客户端update_client.py和另一个可以发送命令update_commander.py的客户端。 http://0.0.0.0:8080/处有一个http端点，列出连接的客户端。当update_commander.py脚本退出其客户端时，可以正确清理它。当update_client.py断开连接时，服务器不会注意到断开连接，并且在update_commander.py发送的其他消息时，我会为每个ghost客户端连接收到错误socket.send() raised exception.。清理代码标有### CLEANUP CODE ###

我觉得我应该做的是当我尝试发送到套接字时捕获错误但没有引发异常，只是向stdout发送消息。

server.py

import uuid
import asyncio
import aiohttp
from aiohttp import web


class Client(object):

    def __init__(self):
        self.websocket = None
        self.name = None


class ClientList(web.View):
    async def get(self):

        clients = self.request.app['clients']

        client_list = [client.name for name, client in clients.items()]
        txt = ", ".join(client_list)
        return web.Response(text=txt)


class WebSocket(web.View):
    async def get(self):
        ws = web.WebSocketResponse()
        await ws.prepare(self.request)

        # session = await get_session(self.request)
        # user = User(self.request.db, {'id': session.get('user')})
        # login = await user.get_login()
        login = str(uuid.uuid4())
        client = Client()
        client.name = login
        client.websocket = ws
        self.request.app['clients'][client.name] = client
        print('%s connected.' % login)

        for _ws in [c.websocket for name, c in self.request.app['clients'].items()]:
            _ws.send_str('%s joined' % login)

        async for msg in ws:
            if msg.tp == aiohttp.WSMsgType.text:
                if msg.data == 'close':
                    await ws.close()
                else:
                    # do something here like save it
                    print('%s sent: %s' % (login, msg.data))
                    # Send message to all clients other clients
                    for _ws in [c.websocket for name, c in self.request.app['clients'].items()]:
                        try:
                            _ws.send_str('(%s) %s' % (login, msg.data))
                            asyncio.sleep(0)
                        except:
                            print(ws.exception())
            elif msg.tp == aiohttp.WSMsgType.error:
                print('ws connection closed with exception %s' % ws.exception())

        ### CLEANUP CODE ###
        await client.websocket.close()
        del self.request.app['clients'][client.name]
        for _ws in [c.websocket for name, c in self.request.app['clients'].items()]:
            _ws.send_str('%s disconected' % login)
        print('%s disconnected' % login)

        return ws


routes = [
    ('GET', '/',        ClientList,  'main'),
    ('GET', '/ws',      WebSocket,   'chat'),
]

app = web.Application()

for route in routes:
    app.router.add_route(route[0], route[1], route[2], name=route[3])
app['clients'] = {}
web.run_app(app)

commander.py

import asyncio
import aiohttp
import os

HOST = os.getenv('HOST', '0.0.0.0')
PORT = int(os.getenv('PORT', 8080))

URL = f'http://{HOST}:{PORT}/ws'


async def main():
    session = aiohttp.ClientSession()
    async with session.ws_connect(URL) as ws:

        await prompt_and_send(ws)
        async for msg in ws:
            print('Message received from server:', msg.data)
            await prompt_and_send(ws)

            if msg.type in (aiohttp.WSMsgType.CLOSED,
                            aiohttp.WSMsgType.ERROR):
                break


async def prompt_and_send(ws):
    new_msg_to_send = input('Type a message to send to the server: ')
    if new_msg_to_send == 'exit':
        print('Exiting!')
        raise SystemExit(0)
    await ws.send_str(new_msg_to_send)


if __name__ == '__main__':
    print('Type "exit" to quit')
    loop = asyncio.get_event_loop()
    loop.run_until_complete(main())

client.py

import aiohttp
import asyncio
import os
import time
import logging
import sys

logging.basicConfig(
        level=logging.DEBUG,

        format='%(name)s: %(message)s',
        stream=sys.stderr,
        )
log = logging.getLogger('main')

HOST = os.getenv('HOST', '0.0.0.0')
PORT = int(os.getenv('PORT', 8080))

URL = f'http://{HOST}:{PORT}/ws'


async def callback(msg):

    if msg == 'time':
        #ws.send_str(time.time())
        print(msg)
    else:
        print(msg)

async def main():
    session = aiohttp.ClientSession()
    async with session.ws_connect(URL) as ws:
        async for msg in ws:
            if msg.type == aiohttp.WSMsgType.TEXT:
                await callback(msg.data)
            elif msg.type == aiohttp.WSMsgType.CLOSED:
                print("CLOSED")
                break
            elif msg.type == aiohttp.WSMsgType.ERROR:
                print("error")
                break

if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    tasks = loop.run_until_complete(main())
    try:
        loop.run_forever()
    except KeyboardInterrupt as e:
        print("Caught keyboard interrupt. Canceling tasks...")
        tasks.cancel()
        loop.run_forever()
    finally:
        log.debug('closing server')
        loop.run_until_complete(loop.shutdown_asyncgens())  # python 3.6 only
        log.debug('closing event loop')
        loop.close()

Answer 1

因此，有时只是将问题清楚地表达给别人帮助。我通过将整个async for msg in ws:包装在try / finally中来修复它。

    try:
        async for msg in ws:
            if msg.tp == aiohttp.WSMsgType.text:
                if msg.data == 'close':
                    await ws.close()
                else:
                    # do something here like save it
                    print('%s sent: %s' % (login, msg.data))
                    # Send message to all clients other clients
                    for _ws in [c.websocket for name, c in self.request.app['clients'].items()]:

                            _ws.send_str('(%s) %s' % (login, msg.data))
            elif msg.tp == aiohttp.WSMsgType.error:
                print('ws connection closed with exception %s' % ws.exception())
    finally:
        await client.websocket.close()
        del self.request.app['clients'][client.name]
        for _ws in [c.websocket for name, c in self.request.app['clients'].items()]:
            _ws.send_str('%s disconected' % login)
        print('%s disconnected' % login)

当客户端不正常退出时，如何检测服务器上的Python aiohttp Web套接字的关闭

1 个答案: