Http client using digest authentication (in python)

Authenticating using http digest isn't too hard. See wikipedia for an overview. But you don't want to implement it yourself if you use a programming language with "batteries included". The python module urllib2 provides one with access to http digest authentication, but it's use isn't straightforward (or documented too well). The key to using urllib is created an HTTPDigestAuthHandler and calling the add_password method on it. To that method pass the realm, url (NOT the uri, the complete url, this is where I got a little stuck), username and password.

See the unittest below (especially the connectWithDigestAuth function).

Sample code

import unittest
import urllib2

def connectWithDigestAuth(url, username, pw, realm):
    authhandler = urllib2.HTTPDigestAuthHandler()
    authhandler.add_password(realm, url, username, pw)
    opener = urllib2.build_opener(authhandler)
    urllib2.install_opener(opener)
    pagehandle = urllib2.urlopen(url)
    lines =  pagehandle.readlines()
    return lines


class testLinebreak(unittest.TestCase):
    def testAuth(self):
        url = "http://localhost/authTest/index.html"
        username = "matt"
        password = "password"
        realm = "/home/spike"
        contents = connectWithDigestAuth(url, username, password, realm)
        self.failUnless('You should be authenticated!\n' in contents)


    def testBadAuth(self):
        url = "http://localhost/authTest/index.html"
        username = "BadUser"
        password = "password"
        realm = "/home/spike"
        self.assertRaises(urllib2.HTTPError, connectWithDigestAuth,url, username, password, realm)

    def testNoAuth(self):
        "a test to make sure this location is protected"
        url = "http://localhost/authTest/index.html"
        req = urllib2.Request(url)
        self.assertRaises(urllib2.HTTPError, urllib2.urlopen, req)
        
if __name__=="__main__":
    unittest.main()

tags: mysql  python  

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