python - Python-如何通过socket.makefile执行套接字通信？

Question

根据对这篇文章的最高评价答案:

Socket : 2 way communication in python

和码头:

https://docs.python.org/3/library/socket.html#targetText=socket.makefile

我试图弄清楚如何使用socket.makefile通过套接字发送/接收。这是我到目前为止的内容:

Server.py:

# Server.py

import socket

# module-level variables
HOST='127.0.0.1'
PORT=65439

ACK_TEXT = 'text_received'


def main():
    # instantiate a socket object
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    print('socket instantiated')

    # bind the socket
    sock.bind((HOST, PORT))
    print('socket binded')

    # start the socket listening
    sock.listen(10)
    print('socket now listening')

    # accept the socket response from the client, get the connection object
    conn, addr = sock.accept()              # Note: execution waits here until the client calls sock.connect()
    print('socket accepted, got connection object')

    sockFile = sock.makefile()

    while True:
        message = sockFile.readline()
        print('received: ' + str(message))
    # end while
# end main

if __name__ == '__main__':
    main()

Client.py:

# Client.py

import socket
import time

# module-level variables
HOST='127.0.0.1'
PORT=65439

ACK_TEXT = 'text_received'


def main():
    # instantiate a socket object
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    print('socket instantiated')

    # connect the socket
    sock.connect((HOST, PORT))    # Note: if execution gets here before the server starts up, this line will cause a crash
    print('socket connected')

    sockFile = sock.makefile(mode='w')

    myCounter = 0
    while True:
        message = 'message ' + str(myCounter)
        print('sending: ' + message)

        sockFile.write(message)

        myCounter += 1
        time.sleep(1)       # wait for 1 sec before sending next text message
    # end while
# end main

if __name__ == '__main__':
    main()

现在，如果我启动服务器，那么来自单独命令提示符的客户端，该客户端似乎正在运行:

Client.py输出:

$ python3 Client.py 
socket instantiated
socket connected
sending: message 0
sending: message 1
sending: message 2
sending: message 3
sending: message 4
sending: message 5

但是服务器失败并显示以下错误:

$ python3 Server.py 
socket instantiated
socket binded
socket now listening
socket accepted, got connection object
Traceback (most recent call last):
  File "Server.py", line 38, in <module>
    main()
  File "Server.py", line 32, in main
    message = sockFile.readline()
  File "/usr/lib/python3.6/socket.py", line 586, in readinto
    return self._sock.recv_into(b)
OSError: [Errno 107] Transport endpoint is not connected

使用 socket.makefile时如何在服务器上成功连接传输终结点？我不确定这种情况下的语法是什么。我最终并没有像使用更传统的方式在服务器上那样使用 conn和 addr，也许这就是我要出问题的地方？

- - 编辑 - -

在 Server.py中，我尝试将 connection与 makefile()函数结合使用，如下所示:

.
.
.
    # accept the socket response from the client, get the connection object
    conn, addr = sock.accept()              # Note: execution waits here until the client calls sock.connect()
    print('socket accepted, got connection object')

    connFile = conn.makefile()

    while True:
        message = connFile.readline()
        print('received: ' + str(message))
    # end while
.
.
.

但这也不起作用， Client.py仍然像以前一样工作，但是现在 Server.py只是挂起了:

$ python3 Server.py 
socket instantiated
socket binded
socket now listening
socket accepted, got connection object
(hangs here forever)

-编辑2-

现在我真的很困惑。根据这篇文章:

https://bugs.python.org/issue35928

我几乎复制了海报代码，因此Server.py现在看起来像这样:

# Server.py

import socket

# module-level variables
HOST='127.0.0.1'
PORT=65439

ACK_TEXT = 'text_received'

def main():
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:

        s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        s.bind((HOST, PORT))

        print(f'Waiting for connection on port {s.getsockname()[1]}')
        s.listen(1)

        conn, addr = s.accept()
        print(f'Connected by {addr}')

        with conn:
            f = conn.makefile(mode='rw')

            while True:
                print('before f.readline()')
                m = f.readline()
                print('after f.readline()')
                print(f'msg: {m!r}')

                if not m:
                    exit(0)

                f.write(m)
                f.flush()

# end main

if __name__ == '__main__':
    main()

且 Server.py仍卡在读取器上!!

$ python3 Server.py 
Waiting for connection on port 65439
Connected by ('127.0.0.1', 47536)
before f.readline()

根据回复中的最后一篇帖子，据说海报的原始关注点已解决，因此现在应该可以解决。我仍然不确定如何做到这一点。

-编辑3-

我正在使用最新更新的 Ubuntu 18.04.3和 Python 3.6.9(如果有关系的话)

Answer 1

在您的服务器代码中:

conn, addr = sock.accept()
calls sock.connect()
sockFile = sock.makefile()

    while True:
        message = sockFile.readline()

您制作了一个客户端套接字(conn)，但从未使用过。
客户端正在写，所以您应该从客户端套接字(conn)中读取
我也认为您应该从while循环内部调用accept。

while True:
        conn, addr = sock.accept()
        sockFile = conn.makefile()
        message = sockFile.readline()