Python 套接字挂起程序

Question

我正在用Python开发一个简单的HTTP服务器。我从这里获取一些零碎的东西：http://hg.python.org/cpython/file/3.3/Lib/socketserver.py 看看 Python 的标准库如何处理它。

我的

问题是，一旦我尝试接受请求，我的程序就会挂起。这是我的代码，它只有 100 行，所以我直接在这里发布它。

我有一个 process（） 函数，它处于一个永远循环的循环中，它应该处理新的连接。在里面，我有一个打印语句，只能打印一次。

print（'processing'） in TCPServer.process（）

我尝试过线程化进程（），但我得到了相同的结果。

"""."""
import socket
import select
from abc import abstractmethod, ABCMeta

class BaseServer(metaclass=ABCMeta):
    def __init__(self, server_address, server_port, RequestHandlerClass):
        self._server_address = server_address
        self._server_port = server_port
        self._RequestHandlerClass = RequestHandlerClass
        self._running = False
    def serve_forever(self):
        self._running = True
        while self._running:
            self.process()
    @abstractmethod
    def process(self):
        pass
    def shutdown(self):
        self._running = False

class TCPServer(BaseServer):
    def __init__(self,
                server_address,
                server_port,
                RequestHandlerClass,
                address_family=socket.AF_INET,
                socket_type=socket.SOCK_STREAM,
                request_queue_size=1,
                bind=True):
        super(TCPServer, self).__init__(server_address,
                                        server_port,
                                        RequestHandlerClass)
        self._address_family = address_family
        self._socket_type = socket_type
        self._request_queue_size = request_queue_size
        self._socket = socket.socket(self._address_family, self._socket_type)
        self._read_list = [self._socket]
        if bind:
            self.bind()
    def bind(self):
        self._socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        self._socket.bind((self._server_address, self._server_port))
        self._socket.listen(self._request_queue_size)
    def shutdown(self):
        super().shutdown()
        self._socket.close()
    def process(self):
        print('processing')
        readable, writeable, errored = select.select(self._read_list, [], [])
        for socket in readable:
            if socket is self._socket:
                client_socket, client_address = self._socket.accept()
                self._read_list.append(client_socket)
                print('connection from: ', client_address)
            else:
                self._RequestHandlerClass(client_socket)
                self._read_list.remove(client_socket)

class BaseRequestHandler(metaclass=ABCMeta):
    def __init__(self, client_socket):
        self._client_socket = client_socket
        self.setup()
        try:
            self.handle()
        finally:
            self.finish()
    @abstractmethod
    def setup(self):
        pass
    @abstractmethod
    def handle(self):
        pass
    @abstractmethod
    def finish(self):
        pass

class HTTPRequestHandler(BaseRequestHandler):
    def setup(self):
        print('REQUEST SETUP')
        print(self._client_socket.recv(2048))
    def handle(self):
        print('REQUEST HANDLE')
    def finish(self):
        print('REQUEST FINISH')
        self._client_socket.close()

if __name__ == '__main__':
    tcp_server = TCPServer(server_address='',
                        server_port=9000,
                        RequestHandlerClass=HTTPRequestHandler)
    tcp_server.serve_forever()

Answer 1

我运行了你的代码，但无法让它挂起。但是，process()函数中存在一个致命错误，在该错误中，您在else:分支中引用client_socket，但此时未定义client_socket。您可能打算指socket.

我能够在端口 9000 上与服务器建立两个连接，并为每个连接获得"连接自："行。一旦其中一个连接发送了某些内容，您的服务器就会由于上述原因而崩溃。