NTLM Authentication with Suds

We have a requirement to hit a SOAP web service running on a Windows box with IIS, and unfortunately this service is protected by NTLM authentication. While basic HTTP authentication is well supported and trivial to implement in Suds -- a Python SOAP client module -- NTLM is not.

There is a great blog entry describing how to solve this problem; however the post recommends placing the code within Suds itself, and I had to make a couple of minor modifications to get it to work with the with the latest Suds version (0.3.6).

Here are (very minor) the modifications to C. Bess's code:

from suds.transport.https import HttpAuthenticated
from suds.transport.http import HttpTransport
from ntlm import HTTPNtlmAuthHandler
import urllib2

class WindowsHttpAuthenticated(HttpAuthenticated):
  """
  Provides Windows (NTLM) http authentication for suds.
  @ivar pm: The password manager.
  @ivar handler: The authentication handler.
  @author: Christopher Bess (modified by Matt Sullivan)
  """
  def __init__(self, **kwargs):
    HttpTransport.__init__(self, **kwargs)
    self.pm = urllib2.HTTPPasswordMgrWithDefaultRealm()
    self.handler =\
      HTTPNtlmAuthHandler.HTTPNtlmAuthHandler(self.pm)
    self.urlopener = urllib2.build_opener(self.handler)
    urllib2.install_opener(self.urlopener)

Using this authentication class is straightforward:

t = WindowsHttpAuthenticated(
  username = 'DOMAIN\%s' %username,
  password = password
)
url = 'http://www.somesite.com/service.asmx?wsdl'
return Client(url, transport = t)