googlecode ：https://code.google.com/archive/p/python-proxy/source/default/source

# -*- coding: cp1252 -*-

# <PythonProxy.py>

#

#Copyright (c) <2009> <F醔io Domingues - fnds3000 in gmail.com>

#

#Permission is hereby granted, free of charge, to any person

#obtaining a copy of this software and associated documentation

#files (the "Software"), to deal in the Software without

#restriction, including without limitation the rights to use,

#copy, modify, merge, publish, distribute, sublicense, and/or sell

#copies of the Software, and to permit persons to whom the

#Software is furnished to do so, subject to the following

#conditions:

#

#The above copyright notice and this permission notice shall be

#included in all copies or substantial portions of the Software.

#

#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

#EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

#OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

#NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

#HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

#WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

#FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

#OTHER DEALINGS IN THE SOFTWARE.

"""\

Copyright (c) <2009> <F醔io Domingues - fnds3000 in gmail.com> <MIT Licence>

                  **************************************

                 *** Python Proxy - A Fast HTTP proxy ***

                  **************************************

Neste momento este proxy ?um Elie Proxy.

Suporta os m閠odos HTTP:

 - OPTIONS;

 - GET;

 - HEAD;

 - POST;

 - PUT;

 - DELETE;

 - TRACE;

 - CONENCT.

Suporta:

 - Conex鮡s dos cliente em IPv4 ou IPv6;

 - Conex鮡s ao alvo em IPv4 e IPv6;

 - Conex鮡s todo o tipo de transmiss鉶 de dados TCP (CONNECT tunneling),

     p.e. liga珲es SSL, como ?o caso do HTTPS.

A fazer:

 - Verificar se o input vindo do cliente est?correcto;

   - Enviar os devidos HTTP erros se n鉶, ou simplesmente quebrar a liga玢o;

 - Criar um gestor de erros;

 - Criar ficheiro log de erros;

 - Colocar excep珲es nos s韙ios onde ?previs韛el a ocorr阯cia de erros,

     p.e.sockets e ficheiros;

 - Rever tudo e melhorar a estrutura do programar e colocar nomes adequados nas

     vari醰eis e m閠odos;

 - Comentar o programa decentemente;

 - Doc Strings.

Funcionalidades futuras:

 - Adiconar a funcionalidade de proxy an髇imo e transparente;

 - Suportar FTP?.

(!) Aten玢o o que se segue s?tem efeito em conex鮡s n鉶 CONNECT, para estas o

 proxy ?sempre Elite.

Qual a diferen鏰 entre um proxy Elite, An髇imo e Transparente?

 - Um proxy elite ?totalmente an髇imo, o servidor que o recebe n鉶 consegue ter

     conhecimento da exist阯cia do proxy e n鉶 recebe o endere鏾 IP do cliente;

 - Quando ?usado um proxy an髇imo o servidor sabe que o cliente est?a usar um

     proxy mas n鉶 sabe o endere鏾 IP do cliente;

     ?enviado o cabe鏰lho HTTP "Proxy-agent".

 - Um proxy transparente fornece ao servidor o IP do cliente e um informa玢o que

     se est?a usar um proxy.

     S鉶 enviados os cabe鏰lhos HTTP "Proxy-agent" e "HTTP_X_FORWARDED_FOR".

"""

import socket, thread, select

__version__ = '0.1.0 Draft 1'

BUFLEN = 8192

VERSION = 'Python Proxy/'+__version__

HTTPVER = 'HTTP/1.1'

class ConnectionHandler:

    def __init__(self, connection, address, timeout):

        self.client = connection

        self.client_buffer = ''

        self.timeout = timeout

        self.method, self.path, self.protocol = self.get_base_header()

        if self.method=='CONNECT':

            self.method_CONNECT()

        elif self.method in ('OPTIONS', 'GET', 'HEAD', 'POST', 'PUT',

                             'DELETE', 'TRACE'):

            self.method_others()

        self.client.close()

        self.target.close()

    def get_base_header(self):

        while 1:

            self.client_buffer += self.client.recv(BUFLEN)

            end = self.client_buffer.find('\n')

            if end!=-1:

                break

        print '%s'%self.client_buffer[:end]#debug

        data = (self.client_buffer[:end+1]).split()

        self.client_buffer = self.client_buffer[end+1:]

        return data

    def method_CONNECT(self):

        self._connect_target(self.path)

        self.client.send(HTTPVER+' 200 Connection established\n'+

                         'Proxy-agent: %s\n\n'%VERSION)

        self.client_buffer = ''

        self._read_write()        

    def method_others(self):

        self.path = self.path[7:]

        i = self.path.find('/')

        host = self.path[:i]

        path = self.path[i:]

        self._connect_target(host)

        self.target.send('%s %s %s\n'%(self.method, path, self.protocol)+

                         self.client_buffer)

        self.client_buffer = ''

        self._read_write()

    def _connect_target(self, host):

        i = host.find(':')

        if i!=-1:

            port = int(host[i+1:])

            host = host[:i]

        else:

            port = 80

        (soc_family, _, _, _, address) = socket.getaddrinfo(host, port)[0]

        self.target = socket.socket(soc_family)

        self.target.connect(address)

    def _read_write(self):

        time_out_max = self.timeout/3

        socs = [self.client, self.target]

        count = 0

        while 1:

            count += 1

            (recv, _, error) = select.select(socs, [], socs, 3)

            if error:

                break

            if recv:

                for in_ in recv:

                    data = in_.recv(BUFLEN)

                    if in_ is self.client:

                        out = self.target

                    else:

                        out = self.client

                    if data:

                        out.send(data)

                        count = 0

            if count == time_out_max:

                break

def start_server(host='', port=8080, IPv6=False, timeout=60,

                  handler=ConnectionHandler):

    if IPv6==True:

        soc_type=socket.AF_INET6

    else:

        soc_type=socket.AF_INET

    soc = socket.socket(soc_type)

    soc.bind((host, port))

    print "Serving on %s:%d."%(host, port)#debug

    soc.listen(0)

    while 1:

        thread.start_new_thread(handler, soc.accept()+(timeout,))

if __name__ == '__main__':

    start_server()