# urllib2 opener to connection through a proxy using the CONNECT method, (useful for SSL)

# tested with python 2.4

import urllib2

import urllib

import httplib

import socket

class ProxyHTTPConnection(httplib.HTTPConnection):

    _ports = {'http' : 80, 'https' : 443}

    def request(self, method, url, body=None, headers={}):

        #request is called before connect, so can interpret url and get

        #real host/port to be used to make CONNECT request to proxy

        proto, rest = urllib.splittype(url)

        if proto is None:

            raise ValueError, "unknown URL type: %s" % url

        #get host

        host, rest = urllib.splithost(rest)

        #try to get port

        host, port = urllib.splitport(host)

        #if port is not defined try to get from proto

        if port is None:

            try:

                port = self._ports[proto]

            except KeyError:

                raise ValueError, "unknown protocol for: %s" % url

        self._real_host = host

        self._real_port = port

        httplib.HTTPConnection.request(self, method, url, body, headers)

    def connect(self):

        httplib.HTTPConnection.connect(self)

        #send proxy CONNECT request

        self.send("CONNECT %s:%d HTTP/1.0\r\n\r\n" % (self._real_host, self._real_port))

        #expect a HTTP/1.0 200 Connection established

        response = self.response_class(self.sock, strict=self.strict, method=self._method)

        (version, code, message) = response._read_status()

        #probably here we can handle auth requests...

        if code != 200:

            #proxy returned and error, abort connection, and raise exception

            self.close()

            raise socket.error, "Proxy connection failed: %d %s" % (code, message.strip())

        #eat up header block from proxy....

        while True:

            #should not use directly fp probablu

            line = response.fp.readline()

            if line == '\r\n': break

class ProxyHTTPSConnection(ProxyHTTPConnection):

    default_port = 443

    def __init__(self, host, port = None, key_file = None, cert_file = None, strict = None):

        ProxyHTTPConnection.__init__(self, host, port)

        self.key_file = key_file

        self.cert_file = cert_file

    def connect(self):

        ProxyHTTPConnection.connect(self)

        #make the sock ssl-aware

        ssl = socket.ssl(self.sock, self.key_file, self.cert_file)

        self.sock = httplib.FakeSocket(self.sock, ssl)

class ConnectHTTPHandler(urllib2.HTTPHandler):

    def do_open(self, http_class, req):

        return urllib2.HTTPHandler.do_open(self, ProxyHTTPConnection, req)

class ConnectHTTPSHandler(urllib2.HTTPSHandler):

    def do_open(self, http_class, req):

        return urllib2.HTTPSHandler.do_open(self, ProxyHTTPSConnection, req)

if __name__ == '__main__':

    import sys

    opener = urllib2.build_opener(ConnectHTTPHandler, ConnectHTTPSHandler)

    urllib2.install_opener(opener)

    req = urllib2.Request(url='http://google.com')

    req.set_proxy('10.101.1.1:80', 'http')

    f = urllib2.urlopen(req)

    print f.read()