实现一个程序, 原意是结合argparse接收命令行参数, 然后通过asyncore进行转发, 从而实现
我在命令行下执行程序监听一个端口,当在浏览器里输入localhost:port的时候,自动转发到远程remoteaddr, 然后再接收转发的conn返回给client,代码是这样的。
import argparse
import asyncore
import socket
LOCAL_SERVER_HOST = 'localhost'
REMOTE_SERVER_HOST = 'www.domain.com'
BUFSIZE = 4096
class PortForward(asyncore.dispatcher):
def __init__(self,ip,port,remoteip,remoteport,backlog=5):
asyncore.dispatcher.__init__(self)
self.remoteip = remoteip
self.remoteport = remoteport
self.create_socket(socket.AF_INET,socket.SOCK_STREAM)
self.set_reuse_addr()
self.bind((ip,port))
self.listen(backlog)
def handle_accept(self):
conn,addr = self.accept()
print('Connected',addr)
Sender(Receiver(conn),self.remoteip,self.remoteport) #这里,是在Sender类里传入一个Receiver类对象方法,与下面的self.receiver = receiver #传入相对应,因为需要使用Sender发送,所以要把传入的receiver绑定成当前自己sender,或者说绑定到sender上。
class Receiver(asyncore.dispatcher):
def __init__(self,conn):
asyncore.dispatcher.__init__(self,conn)
self.from_remote_buffer = ''
self.to_remote_buffer = ''
self.sender = None
def handle_connect(self):
pass
def handle_read(self):
read = self.recv(4096)
self.from_remote_buffer += read
def writable(self):
return (len(self.to_remote_buffer)>0)
def handle_write(self):
sent = self.send(self.to_remote_buffer)
self.to_remote_buffer = self.to_remote_buffer[sent:]
def handle_close(self):
self.close()
if self.sender:
self.sender.close()
class Sender(asyncore.dispatcher):
def __init__(self,receiver,remoteaddr,remoteport):
asyncore.dispatcher.__init__(self)
self.receiver = receiver #传入一个receiver对象
receiver.sender = self #把receiver对象绑定成自己
self.create_socket(socket.AF_INET,socket.SOCK_STREAM)
self.connect((remoteaddr,remoteport))
def handle_connect(self):
pass
def handle_read(self):
read = self.recv(4096)
self.receiver.to_remote_buffer += read #
def writable(self):
return (len(self.receiver.from_remote_buffer)>0)
def handle_write(self):
sent = self.send(self.receiver.from_remote_buffer)
self.receiver.from_remote_buffer = self.receiver.from_remote_buffer[sent:]
def handle_close(self):
self.close()
self.receiver.close()
Sender负责把接收到的发给服务端, Receiver负责把发送返回的conn反馈给client,比较疑惑的就是
self.receiver.from_remote_buffer self.receiver.to_remote_buffer 这么写是什么意思, 为什么要这么写
新手, 也许问题问的并不适合,但真心求教