Parse an HTTP request Authorization header with Python

You can also use urllib2 as [CheryPy][1] does.

here is the snippet:

input= """
 Authorization: Digest qop="chap",
     realm="[email protected]",
     username="Foobear",
     response="6629fae49393a05397450978507c4ef1",
     cnonce="5ccc069c403ebaf9f0171e9517f40e41"
"""
import urllib2
field, sep, value = input.partition("Authorization: Digest ")
if value:
    items = urllib2.parse_http_list(value)
    opts = urllib2.parse_keqv_list(items)
    opts['protocol'] = 'Digest'
    print opts

it outputs:

{'username': 'Foobear', 'protocol': 'Digest', 'qop': 'chap', 'cnonce': '5ccc069c403ebaf9f0171e9517f40e41', 'realm': '[email protected]', 'response': '6629fae49393a05397450978507c4ef1'}

[1]: https://web.archive.org/web/20130118133623/http://www.google.com:80/codesearch/p?hl=en#OQvO9n2mc04/CherryPy-3.0.1/cherrypy/lib/httpauth.py&q=Authorization Digest http lang:python

Here's my pyparsing attempt:

text = """Authorization: Digest qop="chap",
    realm="[email protected]",     
    username="Foobear",     
    response="6629fae49393a05397450978507c4ef1",     
    cnonce="5ccc069c403ebaf9f0171e9517f40e41" """

from pyparsing import *

AUTH = Keyword("Authorization")
ident = Word(alphas,alphanums)
EQ = Suppress("=")
quotedString.setParseAction(removeQuotes)

valueDict = Dict(delimitedList(Group(ident + EQ + quotedString)))
authentry = AUTH + ":" + ident("protocol") + valueDict

print authentry.parseString(text).dump()

which prints:

['Authorization', ':', 'Digest', ['qop', 'chap'], ['realm', '[email protected]'],
 ['username', 'Foobear'], ['response', '6629fae49393a05397450978507c4ef1'], 
 ['cnonce', '5ccc069c403ebaf9f0171e9517f40e41']]
- cnonce: 5ccc069c403ebaf9f0171e9517f40e41
- protocol: Digest
- qop: chap
- realm: [email protected]
- response: 6629fae49393a05397450978507c4ef1
- username: Foobear

I'm not familiar with the RFC, but I hope this gets you rolling.

A little regex:

import re
reg=re.compile('(\w+)[:=] ?"?(\w+)"?')

>>>dict(reg.findall(headers))

{'username': 'Foobear', 'realm': 'testrealm', 'qop': 'chap', 'cnonce': '5ccc069c403ebaf9f0171e9517f40e41', 'response': '6629fae49393a05397450978507c4ef1', 'Authorization': 'Digest'}