设置多线程异步的调用顺序.协议数据已接收

Question

当使用asyncio通过TCP套接字接收多个文件时，我很难处理received_data的调用顺序。当一次发送3个数据流时，我的输出如下：

DEBUG connection_made ('127.0.0.1', 33972) new connection was made
DEBUG connection_made ('127.0.0.1', 33974) new connection was made
DEBUG connection_made ('127.0.0.1', 33976) new connection was made
DEBUG data_received ('127.0.0.1', 33976) data received from new connection
DEBUG data_received ('127.0.0.1', 33974) data received from new connection
DEBUG data_received ('127.0.0.1', 33972) data received from new connection

我假设它的行为类似于从最新到最旧的连接接收数据的堆栈，但这只是猜测。

是否有可能改变这种行为，使数据按照连接的顺序接收？这一点很重要，因为我需要从第一个连接接收的数据来进一步处理以下连接。

我的代码如下：

import asyncio
class AIO(asyncio.Protocol):
def __init__(self):
self.extra = bytearray()
def connection_made(self, transport):
global request_time
peer = transport.get_extra_info('peername')
logger.debug('{} new connection was made'.format(peer))
self.transport = transport
request_time = str(time.time())
def data_received(self, request, msgid=1):
peer = self.transport.get_extra_info('peername')
logger.debug('{} data received from new connection'.format(peer))
self.extra.extend(request)

Answer 1

首先，我建议使用更高级别的流API，而不是传输/协议。然后，如果您需要维护连接时观察到的顺序，您可以使用一系列asyncio.Events自行执行。例如：

import asyncio, itertools
class Comm:
def __init__(self):
self.extra = bytearray()
self.preceding_evt = None
async def serve(self, r, w):
preceding_evt = self.preceding_evt
self.preceding_evt = this_evt = asyncio.Event()
while True:
request = await r.read(4096)
# wait for the preceding connection to receive and store data
# before we store ours
if preceding_evt is not None:
await preceding_evt.wait()
preceding_evt.clear()
# self.extra now contains data from previous connections
self.extra.extend(request)
# inform the subsequent connection that we got data
this_evt.set()
w.close()
async def main():
comm = Comm()
server = await asyncio.start_server(comm.serve, '127.0.0.1', 8888)
async with server:
await server.serve_forever()
asyncio.run(main())