proxy: python3 support no_proxy and vendor socksipy

https://github.com/httplib2/httplib2/issues/11

3 files changed, 505 insertions, 17 deletions

diff --git a/python3/httplib2/__init__.py b/python3/httplib2/__init__.py
index bc82d5a..61e69b2 100644
--- a/python3/httplib2/__init__.py
+++ b/python3/httplib2/__init__.py
@@ -53,8 +53,9 @@ import ssl
 try:
     import socks
 except ImportError:
-    socks = None
-
+    # TODO: remove this fallback and copypasted socksipy module upon py2/3 merge,
+    # idea is to have soft-dependency on any compatible module called socks
+    from . import socks
 from .iri2uri import iri2uri
 
 def has_timeout(timeout):
@@ -745,8 +746,14 @@ class KeyCerts(Credentials):
     pass
 
 
+class AllHosts(object):
+    pass
+
+
 class ProxyInfo(object):
   """Collect information required to use a proxy."""
+  bypass_hosts = ()
+
   def __init__(self, proxy_type, proxy_host, proxy_port, proxy_rdns=True, proxy_user=None, proxy_pass=None, proxy_headers=None):
       """
         Args:
@@ -780,6 +787,21 @@ class ProxyInfo(object):
   def isgood(self):
     return socks and (self.proxy_host != None) and (self.proxy_port != None)
 
+  def applies_to(self, hostname):
+    return not self.bypass_host(hostname)
+
+  def bypass_host(self, hostname):
+    """Has this host been excluded from the proxy config"""
+    if self.bypass_hosts is AllHosts:
+      return True
+
+    bypass = False
+    for domain in self.bypass_hosts:
+      if hostname.endswith(domain):
+        bypass = True
+
+    return bypass
+
 
 def proxy_info_from_environment(method='http'):
     """
@@ -792,10 +814,10 @@ def proxy_info_from_environment(method='http'):
     url = os.environ.get(env_var, os.environ.get(env_var.upper()))
     if not url:
         return
-    return proxy_info_from_url(url, method)
+    return proxy_info_from_url(url, method, noproxy=None)
 
 
-def proxy_info_from_url(url, method='http'):
+def proxy_info_from_url(url, method='http', noproxy=None):
     """
     Construct a ProxyInfo from a URL (such as http_proxy env var)
     """
@@ -821,16 +843,30 @@ def proxy_info_from_url(url, method='http'):
     else:
         port = dict(https=443, http=80)[method]
 
-    proxy_type = 3 # socks.PROXY_TYPE_HTTP
-    return ProxyInfo(
-        proxy_type = proxy_type,
-        proxy_host = host,
-        proxy_port = port,
-        proxy_user = username or None,
-        proxy_pass = password or None,
-        proxy_headers = None,
+    proxy_type = 3  # socks.PROXY_TYPE_HTTP
+    pi = ProxyInfo(
+        proxy_type=proxy_type,
+        proxy_host=host,
+        proxy_port=port,
+        proxy_user=username or None,
+        proxy_pass=password or None,
+        proxy_headers=None,
     )
 
+    bypass_hosts = []
+    # If not given an explicit noproxy value, respect values in env vars.
+    if noproxy is None:
+        noproxy = os.environ.get('no_proxy', os.environ.get('NO_PROXY', ''))
+    # Special case: A single '*' character means all hosts should be bypassed.
+    if noproxy == '*':
+        bypass_hosts = AllHosts
+    elif noproxy.strip():
+        bypass_hosts = noproxy.split(',')
+        bypass_hosts = tuple(filter(bool, bypass_hosts))  # To exclude empty string.
+
+    pi.bypass_hosts = bypass_hosts
+    return pi
+
 
 class HTTPConnectionWithTimeout(http.client.HTTPConnection):
     """HTTPConnection subclass that supports timeouts
diff --git a/python3/httplib2/socks.py b/python3/httplib2/socks.py
new file mode 100644
index 0000000..dbbe511
--- /dev/null
+++ b/python3/httplib2/socks.py
@@ -0,0 +1,448 @@
+"""SocksiPy - Python SOCKS module.
+Version 1.00
+
+Copyright 2006 Dan-Haim. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+3. Neither the name of Dan Haim nor the names of his contributors may be used
+   to endorse or promote products derived from this software without specific
+   prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY DAN HAIM "AS IS" AND ANY EXPRESS OR IMPLIED
+WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+EVENT SHALL DAN HAIM OR HIS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMANGE.
+
+
+This module provides a standard socket-like interface for Python
+for tunneling connections through SOCKS proxies.
+
+"""
+
+"""
+
+Minor modifications made by Christopher Gilbert (http://motomastyle.com/)
+for use in PyLoris (http://pyloris.sourceforge.net/)
+
+Minor modifications made by Mario Vilas (http://breakingcode.wordpress.com/)
+mainly to merge bug fixes found in Sourceforge
+
+"""
+
+import base64
+import socket
+import struct
+import sys
+
+if getattr(socket, 'socket', None) is None:
+    raise ImportError('socket.socket missing, proxy support unusable')
+
+PROXY_TYPE_SOCKS4 = 1
+PROXY_TYPE_SOCKS5 = 2
+PROXY_TYPE_HTTP = 3
+PROXY_TYPE_HTTP_NO_TUNNEL = 4
+
+_defaultproxy = None
+_orgsocket = socket.socket
+
+class ProxyError(Exception): pass
+class GeneralProxyError(ProxyError): pass
+class Socks5AuthError(ProxyError): pass
+class Socks5Error(ProxyError): pass
+class Socks4Error(ProxyError): pass
+class HTTPError(ProxyError): pass
+
+_generalerrors = ("success",
+    "invalid data",
+    "not connected",
+    "not available",
+    "bad proxy type",
+    "bad input")
+
+_socks5errors = ("succeeded",
+    "general SOCKS server failure",
+    "connection not allowed by ruleset",
+    "Network unreachable",
+    "Host unreachable",
+    "Connection refused",
+    "TTL expired",
+    "Command not supported",
+    "Address type not supported",
+    "Unknown error")
+
+_socks5autherrors = ("succeeded",
+    "authentication is required",
+    "all offered authentication methods were rejected",
+    "unknown username or invalid password",
+    "unknown error")
+
+_socks4errors = ("request granted",
+    "request rejected or failed",
+    "request rejected because SOCKS server cannot connect to identd on the client",
+    "request rejected because the client program and identd report different user-ids",
+    "unknown error")
+
+def setdefaultproxy(proxytype=None, addr=None, port=None, rdns=True, username=None, password=None):
+    """setdefaultproxy(proxytype, addr[, port[, rdns[, username[, password]]]])
+    Sets a default proxy which all further socksocket objects will use,
+    unless explicitly changed.
+    """
+    global _defaultproxy
+    _defaultproxy = (proxytype, addr, port, rdns, username, password)
+
+def wrapmodule(module):
+    """wrapmodule(module)
+    Attempts to replace a module's socket library with a SOCKS socket. Must set
+    a default proxy using setdefaultproxy(...) first.
+    This will only work on modules that import socket directly into the namespace;
+    most of the Python Standard Library falls into this category.
+    """
+    if _defaultproxy != None:
+        module.socket.socket = socksocket
+    else:
+        raise GeneralProxyError((4, "no proxy specified"))
+
+class socksocket(socket.socket):
+    """socksocket([family[, type[, proto]]]) -> socket object
+    Open a SOCKS enabled socket. The parameters are the same as
+    those of the standard socket init. In order for SOCKS to work,
+    you must specify family=AF_INET, type=SOCK_STREAM and proto=0.
+    """
+
+    def __init__(self, family=socket.AF_INET, type=socket.SOCK_STREAM, proto=0, _sock=None):
+        _orgsocket.__init__(self, family, type, proto, _sock)
+        if _defaultproxy != None:
+            self.__proxy = _defaultproxy
+        else:
+            self.__proxy = (None, None, None, None, None, None)
+        self.__proxysockname = None
+        self.__proxypeername = None
+        self.__httptunnel = True
+
+    def __recvall(self, count):
+        """__recvall(count) -> data
+        Receive EXACTLY the number of bytes requested from the socket.
+        Blocks until the required number of bytes have been received.
+        """
+        data = self.recv(count)
+        while len(data) < count:
+            d = self.recv(count-len(data))
+            if not d: raise GeneralProxyError((0, "connection closed unexpectedly"))
+            data = data + d
+        return data
+
+    def sendall(self, content, *args):
+        """ override socket.socket.sendall method to rewrite the header
+        for non-tunneling proxies if needed
+        """
+        if not self.__httptunnel:
+            content = self.__rewriteproxy(content)
+        return super(socksocket, self).sendall(content, *args)
+
+    def __rewriteproxy(self, header):
+        """ rewrite HTTP request headers to support non-tunneling proxies
+        (i.e. those which do not support the CONNECT method).
+        This only works for HTTP (not HTTPS) since HTTPS requires tunneling.
+        """
+        host, endpt = None, None
+        hdrs = header.split("\r\n")
+        for hdr in hdrs:
+            if hdr.lower().startswith("host:"):
+                host = hdr
+            elif hdr.lower().startswith("get") or hdr.lower().startswith("post"):
+                endpt = hdr
+        if host and endpt:
+            hdrs.remove(host)
+            hdrs.remove(endpt)
+            host = host.split(" ")[1]
+            endpt = endpt.split(" ")
+            if (self.__proxy[4] != None and self.__proxy[5] != None):
+                hdrs.insert(0, self.__getauthheader())
+            hdrs.insert(0, "Host: %s" % host)
+            hdrs.insert(0, "%s http://%s%s %s" % (endpt[0], host, endpt[1], endpt[2]))
+        return "\r\n".join(hdrs)
+
+    def __getauthheader(self):
+        auth = self.__proxy[4] + ":" + self.__proxy[5]
+        return "Proxy-Authorization: Basic " + base64.b64encode(auth)
+
+    def setproxy(self, proxytype=None, addr=None, port=None, rdns=True, username=None, password=None, headers=None):
+        """setproxy(proxytype, addr[, port[, rdns[, username[, password]]]])
+        Sets the proxy to be used.
+        proxytype -    The type of the proxy to be used. Three types
+                are supported: PROXY_TYPE_SOCKS4 (including socks4a),
+                PROXY_TYPE_SOCKS5 and PROXY_TYPE_HTTP
+        addr -        The address of the server (IP or DNS).
+        port -        The port of the server. Defaults to 1080 for SOCKS
+                servers and 8080 for HTTP proxy servers.
+        rdns -        Should DNS queries be preformed on the remote side
+                (rather than the local side). The default is True.
+                Note: This has no effect with SOCKS4 servers.
+        username -    Username to authenticate with to the server.
+                The default is no authentication.
+        password -    Password to authenticate with to the server.
+                Only relevant when username is also provided.
+        headers -     Additional or modified headers for the proxy connect request.
+        """
+        self.__proxy = (proxytype, addr, port, rdns, username, password, headers)
+
+    def __negotiatesocks5(self, destaddr, destport):
+        """__negotiatesocks5(self,destaddr,destport)
+        Negotiates a connection through a SOCKS5 server.
+        """
+        # First we'll send the authentication packages we support.
+        if (self.__proxy[4]!=None) and (self.__proxy[5]!=None):
+            # The username/password details were supplied to the
+            # setproxy method so we support the USERNAME/PASSWORD
+            # authentication (in addition to the standard none).
+            self.sendall(struct.pack('BBBB', 0x05, 0x02, 0x00, 0x02))
+        else:
+            # No username/password were entered, therefore we
+            # only support connections with no authentication.
+            self.sendall(struct.pack('BBB', 0x05, 0x01, 0x00))
+        # We'll receive the server's response to determine which
+        # method was selected
+        chosenauth = self.__recvall(2)
+        if chosenauth[0:1] != chr(0x05).encode():
+            self.close()
+            raise GeneralProxyError((1, _generalerrors[1]))
+        # Check the chosen authentication method
+        if chosenauth[1:2] == chr(0x00).encode():
+            # No authentication is required
+            pass
+        elif chosenauth[1:2] == chr(0x02).encode():
+            # Okay, we need to perform a basic username/password
+            # authentication.
+            self.sendall(chr(0x01).encode() + chr(len(self.__proxy[4])) + self.__proxy[4] + chr(len(self.__proxy[5])) + self.__proxy[5])
+            authstat = self.__recvall(2)
+            if authstat[0:1] != chr(0x01).encode():
+                # Bad response
+                self.close()
+                raise GeneralProxyError((1, _generalerrors[1]))
+            if authstat[1:2] != chr(0x00).encode():
+                # Authentication failed
+                self.close()
+                raise Socks5AuthError((3, _socks5autherrors[3]))
+            # Authentication succeeded
+        else:
+            # Reaching here is always bad
+            self.close()
+            if chosenauth[1] == chr(0xFF).encode():
+                raise Socks5AuthError((2, _socks5autherrors[2]))
+            else:
+                raise GeneralProxyError((1, _generalerrors[1]))
+        # Now we can request the actual connection
+        req = struct.pack('BBB', 0x05, 0x01, 0x00)
+        # If the given destination address is an IP address, we'll
+        # use the IPv4 address request even if remote resolving was specified.
+        try:
+            ipaddr = socket.inet_aton(destaddr)
+            req = req + chr(0x01).encode() + ipaddr
+        except socket.error:
+            # Well it's not an IP number,  so it's probably a DNS name.
+            if self.__proxy[3]:
+                # Resolve remotely
+                ipaddr = None
+                req = req + chr(0x03).encode() + chr(len(destaddr)).encode() + destaddr.encode()
+            else:
+                # Resolve locally
+                ipaddr = socket.inet_aton(socket.gethostbyname(destaddr))
+                req = req + chr(0x01).encode() + ipaddr
+        req = req + struct.pack(">H", destport)
+        self.sendall(req)
+        # Get the response
+        resp = self.__recvall(4)
+        if resp[0:1] != chr(0x05).encode():
+            self.close()
+            raise GeneralProxyError((1, _generalerrors[1]))
+        elif resp[1:2] != chr(0x00).encode():
+            # Connection failed
+            self.close()
+            if ord(resp[1:2])<=8:
+                raise Socks5Error((ord(resp[1:2]), _socks5errors[ord(resp[1:2])]))
+            else:
+                raise Socks5Error((9, _socks5errors[9]))
+        # Get the bound address/port
+        elif resp[3:4] == chr(0x01).encode():
+            boundaddr = self.__recvall(4)
+        elif resp[3:4] == chr(0x03).encode():
+            resp = resp + self.recv(1)
+            boundaddr = self.__recvall(ord(resp[4:5]))
+        else:
+            self.close()
+            raise GeneralProxyError((1,_generalerrors[1]))
+        boundport = struct.unpack(">H", self.__recvall(2))[0]
+        self.__proxysockname = (boundaddr, boundport)
+        if ipaddr != None:
+            self.__proxypeername = (socket.inet_ntoa(ipaddr), destport)
+        else:
+            self.__proxypeername = (destaddr, destport)
+
+    def getproxysockname(self):
+        """getsockname() -> address info
+        Returns the bound IP address and port number at the proxy.
+        """
+        return self.__proxysockname
+
+    def getproxypeername(self):
+        """getproxypeername() -> address info
+        Returns the IP and port number of the proxy.
+        """
+        return _orgsocket.getpeername(self)
+
+    def getpeername(self):
+        """getpeername() -> address info
+        Returns the IP address and port number of the destination
+        machine (note: getproxypeername returns the proxy)
+        """
+        return self.__proxypeername
+
+    def __negotiatesocks4(self,destaddr,destport):
+        """__negotiatesocks4(self,destaddr,destport)
+        Negotiates a connection through a SOCKS4 server.
+        """
+        # Check if the destination address provided is an IP address
+        rmtrslv = False
+        try:
+            ipaddr = socket.inet_aton(destaddr)
+        except socket.error:
+            # It's a DNS name. Check where it should be resolved.
+            if self.__proxy[3]:
+                ipaddr = struct.pack("BBBB", 0x00, 0x00, 0x00, 0x01)
+                rmtrslv = True
+            else:
+                ipaddr = socket.inet_aton(socket.gethostbyname(destaddr))
+        # Construct the request packet
+        req = struct.pack(">BBH", 0x04, 0x01, destport) + ipaddr
+        # The username parameter is considered userid for SOCKS4
+        if self.__proxy[4] != None:
+            req = req + self.__proxy[4]
+        req = req + chr(0x00).encode()
+        # DNS name if remote resolving is required
+        # NOTE: This is actually an extension to the SOCKS4 protocol
+        # called SOCKS4A and may not be supported in all cases.
+        if rmtrslv:
+            req = req + destaddr + chr(0x00).encode()
+        self.sendall(req)
+        # Get the response from the server
+        resp = self.__recvall(8)
+        if resp[0:1] != chr(0x00).encode():
+            # Bad data
+            self.close()
+            raise GeneralProxyError((1,_generalerrors[1]))
+        if resp[1:2] != chr(0x5A).encode():
+            # Server returned an error
+            self.close()
+            if ord(resp[1:2]) in (91, 92, 93):
+                self.close()
+                raise Socks4Error((ord(resp[1:2]), _socks4errors[ord(resp[1:2]) - 90]))
+            else:
+                raise Socks4Error((94, _socks4errors[4]))
+        # Get the bound address/port
+        self.__proxysockname = (socket.inet_ntoa(resp[4:]), struct.unpack(">H", resp[2:4])[0])
+        if rmtrslv != None:
+            self.__proxypeername = (socket.inet_ntoa(ipaddr), destport)
+        else:
+            self.__proxypeername = (destaddr, destport)
+
+    def __negotiatehttp(self, destaddr, destport):
+        """__negotiatehttp(self,destaddr,destport)
+        Negotiates a connection through an HTTP server.
+        """
+        # If we need to resolve locally, we do this now
+        if not self.__proxy[3]:
+            addr = socket.gethostbyname(destaddr)
+        else:
+            addr = destaddr
+        headers =  ["CONNECT ", addr, ":", str(destport), " HTTP/1.1\r\n"]
+        wrote_host_header = False
+        wrote_auth_header = False
+        if self.__proxy[6] != None:
+            for key, val in self.__proxy[6].iteritems():
+                headers += [key, ": ", val, "\r\n"]
+                wrote_host_header = (key.lower() == "host")
+                wrote_auth_header = (key.lower() == "proxy-authorization")
+        if not wrote_host_header:
+            headers += ["Host: ", destaddr, "\r\n"]
+        if not wrote_auth_header:
+            if (self.__proxy[4] != None and self.__proxy[5] != None):
+                headers += [self.__getauthheader(), "\r\n"]
+        headers.append("\r\n")
+        self.sendall("".join(headers).encode())
+        # We read the response until we get the string "\r\n\r\n"
+        resp = self.recv(1)
+        while resp.find("\r\n\r\n".encode()) == -1:
+            resp = resp + self.recv(1)
+        # We just need the first line to check if the connection
+        # was successful
+        statusline = resp.splitlines()[0].split(" ".encode(), 2)
+        if statusline[0] not in ("HTTP/1.0".encode(), "HTTP/1.1".encode()):
+            self.close()
+            raise GeneralProxyError((1, _generalerrors[1]))
+        try:
+            statuscode = int(statusline[1])
+        except ValueError:
+            self.close()
+            raise GeneralProxyError((1, _generalerrors[1]))
+        if statuscode != 200:
+            self.close()
+            raise HTTPError((statuscode, statusline[2]))
+        self.__proxysockname = ("0.0.0.0", 0)
+        self.__proxypeername = (addr, destport)
+
+    def connect(self, destpair):
+        """connect(self, despair)
+        Connects to the specified destination through a proxy.
+        destpar - A tuple of the IP/DNS address and the port number.
+        (identical to socket's connect).
+        To select the proxy server use setproxy().
+        """
+        # Do a minimal input check first
+        if (not type(destpair) in (list,tuple)) or (len(destpair) < 2) or (not isinstance(destpair[0], basestring)) or (type(destpair[1]) != int):
+            raise GeneralProxyError((5, _generalerrors[5]))
+        if self.__proxy[0] == PROXY_TYPE_SOCKS5:
+            if self.__proxy[2] != None:
+                portnum = self.__proxy[2]
+            else:
+                portnum = 1080
+            _orgsocket.connect(self, (self.__proxy[1], portnum))
+            self.__negotiatesocks5(destpair[0], destpair[1])
+        elif self.__proxy[0] == PROXY_TYPE_SOCKS4:
+            if self.__proxy[2] != None:
+                portnum = self.__proxy[2]
+            else:
+                portnum = 1080
+            _orgsocket.connect(self,(self.__proxy[1], portnum))
+            self.__negotiatesocks4(destpair[0], destpair[1])
+        elif self.__proxy[0] == PROXY_TYPE_HTTP:
+            if self.__proxy[2] != None:
+                portnum = self.__proxy[2]
+            else:
+                portnum = 8080
+            _orgsocket.connect(self,(self.__proxy[1], portnum))
+            self.__negotiatehttp(destpair[0], destpair[1])
+        elif self.__proxy[0] == PROXY_TYPE_HTTP_NO_TUNNEL:
+            if self.__proxy[2] != None:
+                portnum = self.__proxy[2]
+            else:
+                portnum = 8080
+            _orgsocket.connect(self,(self.__proxy[1],portnum))
+            if destpair[1] == 443:
+                self.__negotiatehttp(destpair[0],destpair[1])
+            else:
+                self.__httptunnel = False
+        elif self.__proxy[0] == None:
+            _orgsocket.connect(self, (destpair[0], destpair[1]))
+        else:
+            raise GeneralProxyError((4, _generalerrors[4]))
diff --git a/tests/test_proxy.py b/tests/test_proxy.py
index 9d75f78..d1bdb66 100644
--- a/tests/test_proxy.py
+++ b/tests/test_proxy.py
@@ -4,8 +4,6 @@ Must use pytest --forked or similar technique.
 '''
 import httplib2
 import os
-import pytest
-import sys
 # import tests
 
 
@@ -45,7 +43,6 @@ def test_from_env_none():
     assert pi is None
 
 
-@pytest.mark.skipif(sys.version_info >= (3,), reason='FIXME: https://github.com/httplib2/httplib2/issues/53')
 def test_applies_to():
     os.environ['http_proxy'] = 'http://myproxy.example.com:80'
     os.environ['https_proxy'] = 'http://myproxy.example.com:81'
@@ -56,7 +53,15 @@ def test_applies_to():
     assert not pi.applies_to('www.example.com')
 
 
-@pytest.mark.skipif(sys.version_info >= (3,), reason='FIXME: https://github.com/httplib2/httplib2/issues/53')
+def test_noproxy_trailing_comma():
+    os.environ['http_proxy'] = 'http://myproxy.example.com:80'
+    os.environ['no_proxy'] = 'localhost,other.host,'
+    pi = httplib2.proxy_info_from_environment()
+    assert not pi.applies_to('localhost')
+    assert not pi.applies_to('other.host')
+    assert pi.applies_to('example.domain')
+
+
 def test_noproxy_star():
     os.environ['http_proxy'] = 'http://myproxy.example.com:80'
     os.environ['NO_PROXY'] = '*'
@@ -65,7 +70,6 @@ def test_noproxy_star():
         assert not pi.applies_to(host)
 
 
-@pytest.mark.skipif(sys.version_info >= (3,), reason='FIXME: https://github.com/httplib2/httplib2/issues/53')
 def test_headers():
     headers = {'key0': 'val0', 'key1': 'val1'}
     pi = httplib2.ProxyInfo(httplib2.socks.PROXY_TYPE_HTTP, 'localhost', 1234, proxy_headers=headers)