python-asyncio - 获取 OSError : (Address already in use) while runnning a function that uses trio-sockets in a while loop

Question

代码

import trio
from trio import socket

async def listen(host, port):
   while True:
        fullmsg = ""
        sock = socket.socket()
        await sock.bind((host, port))
        sock.listen()
        print(f'Awaiting Receive On {host}:{port}')
        conn, addr = await sock.accept()
        print(f'Connection Received From {addr[0]}:{addr[1]}')
        while True:
            try:
                msg = await conn.recv(8)
                if len(msg.decode().strip()) > 0:
                    print(f'Received {len(msg.strip())} bytes')
                    fullmsg += msg.decode().strip()
                else:
                    break
            except Exception as e:
                print(f'DEBUG: {e}')
        sock.shutdown(0)
        sock.close()
        print(fullmsg)


# function that runs the listen function:
async def create():
    async with trio.open_nursery() as nursery:
            nursery.start_soon(listen, '127.0.0.1', 6969)


# To run the program
trio.run(create)

我想在每次收到长度为 0 的消息或连接被客户端关闭时一遍又一遍地运行该函数，但是当该函数完成第一个 while 循环的第一次迭代时，它会给出一个 OSError 说端口已经正在使用。我在循环结束时关闭并关闭了我的套接字，但我仍然不知道程序在哪里出错。

程序的输出

Awaiting Receive On 127.0.0.1:6969
Connection Received From 127.0.0.1:37122
Received 8 bytes
Received 5 bytes
Hello, World!
Traceback (most recent call last):
  File "./ape.py", line 68, in <module>
    trio.run(create)
  File "/usr/local/lib/python3.8/dist-packages/trio/_core/_run.py", line 1804, in run
    raise runner.main_task_outcome.error
  File "./ape.py", line 59, in create
    nursery.start_soon(listen, '127.0.0.1', 6969)
  File "/usr/local/lib/python3.8/dist-packages/trio/_core/_run.py", line 730, in __aexit__
    raise combined_error_from_nursery
  File "./ape.py", line 15, in listen
    await sock.bind((host, port))
  File "/usr/local/lib/python3.8/dist-packages/trio/_socket.py", line 473, in bind
    return self._sock.bind(address)
OSError: [Errno 98] Address already in use

Answer 1

就像其他人在评论中所说的那样，问题是在 Unix-y 平台上，您必须设置 SO_REUSEADDR如果您希望能够关闭监听套接字，然后立即打开一个绑定(bind)到同一端口的新套接字，请使用套接字选项。

但请注意，在 Windows 上，您永远不应该设置 SO_REUSEADDR选项，因为在 Windows 上，您想要的行为默认启用，SO_REUSEADDR被重新定义为“关闭安全”选项。
trio.socket非常底层并且暴露了所有这些细节，所以如果你想自己处理它们，它可以让你这样做。但大多数用户最好使用更高级的助手，如 trio.serve_tcp。 ，它将自动处理很多这些细节。