真难以自信，使用Python强大的类库，可以用这么简短的代码就写好一个本地的HTTP代理！
真难以自信，这是我用Python花了连续6个小时写的第一个程序（之前写的一个Hello world除外）！
真难以自信，我就这样爱上了Python……
所以，以后在我博客上估计会有不少Python代码了……

现在我使用Python仍然停留在Thinking In The C++ Way而不是Thinking In The Python Way，所以最近会打算看一些Python类库里面的代码，看看别人是如何写的。

一开始使用Python3.2编写这个代理服务器，后来移植到Python2.7上去，这两个版本的差异还真的挺大的，我记得移植的时候改了不少地方。
我用py2exe编译了不需要Python运行环境的Windows可执行文件版本，方便大家测试，貌似编译之后比较臃肿。

这里有一篇关于如何使用py2exe编译python脚本的文章：
www.cnblogs.com/jans2002/archive/2006/09/30/519393.html

下载地址：sogouproxy win32

Python源代码：

'''
    Hey guys!
    This is a the first python program(except hello worlds) I have written. 
    With HTTPServer, I can easily write a webserver.
    Python is such a powerful language that many complicated problems can be
    solved by a few lines of code.

    Welcome to visit my blog: www.xiaoxia.org
    The proxy program is just coded for fun :-)
'''

from threading import Thread
from struct import unpack
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
from httplib import HTTPResponse
from SocketServer import ThreadingMixIn
import socket
import time, sys, random

x_sogou_auth = "9CD285F1E7ADB0BD403C22AD1D545F40/30/853edc6d49ba4e27"
proxy_host = "h0.cnc.bj.ie.sogou.com"
proxy_port = 80

def calc_sogou_hash(t, host):
    s = (t + host + 'SogouExplorerProxy').encode('ascii')
    code = len(s)
    dwords = int(len(s)/4)
    rest = len(s) % 4
    v = unpack(str(dwords) + 'i'+str(rest)+'s', s)
    for vv in v:
        if(type(vv)==type('i')):
            break
        a = (vv & 0xFFFF)
        b = (vv >> 16)
        code += a
        code = code ^ (((code<<5)^b) << 0xb)
        # To avoid overflows
        code &= 0xffffffff
        code += code >> 0xb
    if rest == 3:
        code += ord(s[len(s)-2]) * 256 + ord(s[len(s)-3])
        code = code ^ ((code ^ (ord(s[len(s)-1])*4)) << 0x10)
        code &= 0xffffffff
        code += code >> 0xb
    elif rest == 2:
        code += ord(s[len(s)-1]) * 256 + ord(s[len(s)-2])
        code ^= code << 0xb
        code &= 0xffffffff
        code += code >> 0x11
    elif rest == 1:
        code += ord(s[len(s)-1])
        code ^= code << 0xa
        code &= 0xffffffff
        code += code >> 0x1
    code ^= code * 8
    code &= 0xffffffff
    code += code >> 5
    code ^= code << 4
    code = code & 0xffffffff
    code += code >> 0x11
    code ^= code << 0x19
    code = code & 0xffffffff
    code += code >> 6
    code = code & 0xffffffff
    return hex(code)[2:].rstrip('L').zfill(8)

class Handler(BaseHTTPRequestHandler):
    s = 0
    def do_proxy(self):
        try:
            if self.s == 0:
                self.s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                self.s.connect((proxy_host, proxy_port))
            self.s.send(self.requestline.encode('ascii') + b"\r\n")
            # Add Sogou Verification Tags
            self.headers["X-Sogou-Auth"] = x_sogou_auth
            t = hex(int(time.time()))[2:].rstrip('L').zfill(8)
            self.headers["X-Sogou-Tag"] = calc_sogou_hash(t, self.headers['Host'])
            self.headers["X-Sogou-Timestamp"] = t
            self.s.send(str(self.headers).encode('ascii') + b"\r\n")
            # Send Post data
            if(self.command=='POST'):
                self.s.send(self.rfile.read(int(self.headers['Content-Length'])))
            response = HTTPResponse(self.s, method=self.command, buffering=True)
            response.begin()
            # Reply to the browser
            status = "HTTP/1.1 " + str(response.status) + " " + response.reason
            self.wfile.write(status.encode('ascii') + b'\r\n')
            h = ''
            for hh, vv in response.getheaders():
                if hh.upper()!='TRANSFER-ENCODING':
                    h += hh + ': ' + vv + '\r\n'
            self.wfile.write(h.encode('ascii') + b'\r\n')
            while True:
                response_data = response.read(8192)
                if(len(response_data) == 0):
                    break
                self.wfile.write(response_data)
        except socket.error:
            print('socket error for ' + self.requestline)
    def do_POST(self):
        self.do_proxy()
    def do_GET(self):
        self.do_proxy()

class ThreadingHTTPServer(ThreadingMixIn, HTTPServer):
    pass

server = ThreadingHTTPServer(("127.0.0.1", 1998), Handler)

#print(calc_sogou_hash('4d8cdaed', 'www.youku.com'))

print('Please select your network:\n\
      1. CERNET(The China Education and Research Network)\n\
      2. CTCNET(China Telecommunications Corporation)\n\
      3. CNCNET(China NetCom)\n\
      4. DXT(Dian Xin Tong)\n')
i = int(input('Input the number: '))
if i==1:
    proxy_host = 'h' + str(random.randint(0,10)) + '.edu.bj.ie.sogou.com'
elif i==2:
    proxy_host = 'h' + str(random.randint(0,3)) + '.ctc.bj.ie.sogou.com'
elif i==3:
    proxy_host = 'h' + str(random.randint(0,3)) + '.cnc.bj.ie.sogou.com'
elif i==4:
    proxy_host = 'h' + str(random.randint(0,10)) + '.dxt.bj.ie.sogou.com'

print('Proxy over ' + proxy_host)
server.serve_forever()