我已经走到了尽头 - 我无法想象这一点 . 我是Python的新手,我正在编写一个TCP服务器/客户端应用程序 .
服务器侦听连接并生成线程以处理连接 . 通信非常简单 - 客户端 Build 连接,发送消息,服务器响应然后关闭连接(ala HTTP)
问题是我的服务器代码不能始终从客户端接收任何数据 . 服务器接受新连接,旋转新线程,然后阻止.recv方法 .
Server Listener
class TCPListener(threading.Thread):
def __init__(self, ip = settings.BIND_IP, port = settings.BIND_PORT):
super(TCPListener, self).__init__()
self.daemon = True
self._port = port
self._ip = ip
self.stop = threading.Event()
self.stop.clear()
self.tcp_server_socket = socket(AF_INET, SOCK_STREAM)
self.tcp_server_socket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
self.tcp_server_socket.setblocking(False)
self.tcp_server_socket.bind((self._ip, self._port))
def run(self):
# Listen for client connection requests
with lock:
utils.log_message("Listening for ledger messages on port {0}".format(self._port))
try:
self.tcp_server_socket.listen(5)
# List for managing spawned threads
socket_threads = []
# Non-blocking socket loop that can be interrupted with a signal/event
while True and not self.stop.is_set():
try:
client_socket, address = self.tcp_server_socket.accept()
# Spawn thread
client_thread = TCPConnectionThread(client_socket)
client_thread.start()
socket_threads.append(client_thread)
except Exception as e:
continue
# Clean up all the threads
for thread in socket_threads:
thread.join()
except Exception as e:
print("Could not bind to port: {0}".format(e))
finally:
self.tcp_server_socket.close()
Server Connection Handler
class TCPConnectionThread(threading.Thread):
def __init__(self, socket):
super(TCPConnectionThread, self).__init__()
with lock:
utils.log_message("Spawning TCP Connection Thread from {0}".format(socket.getsockname()))
self._socket = socket
def run(self):
# Get message
message = ''
data = True
while data:
data = self._socket.recv(4096) #BLOCKS HERE 99% OF THE TIME
message+=data.decode()
with lock:
utils.log_message("Received message from {0}:\n{1}".format(self._socket.getsockname(), message))
self._socket.sendall(response)
self._socket.close()
从我的客户端处理连接的线程只是阻塞 . 如果我在该点(socket.recv)上放置一个断点,它可能会收到数据,但如果我正常运行它会无限期地阻塞 . 我不确定为什么调试它会影响它,也许会引入延迟?我可以在wireshark中看到客户端正在发送消息而服务器确认它,但它永远不会从recv()返回 .
任何帮助将不胜感激 . 我浪费了太多时间在最有可能是一个简单的bug上 .
2 回答
self._socket.recv
是阻止通话 . 它将阻塞,直到它在套接字上接收数据 . 我认为问题是:服务器接收数据但再次进入循环并等待进一步的数据 . 退出循环的标准是什么?如果客户端发送数据但未断开连接,则循环将始终处于活动状态 . 只有当客户端断开连接时,循环才会中断 .
我相信你为自己制造的东西过于复杂 . 请参阅Python Cookbook中的以下示例:
至少这个:
应该照顾你的阻止问题 .