from paste.httpheaders import REQUEST_METHOD
from paste.httpheaders import CONTENT_TYPE
from paste.httpheaders import USER_AGENT
from paste.httpheaders import WWW_AUTHENTICATE
import zope.interface
from repoze.who.interfaces import IRequestClassifier
from repoze.who.interfaces import IChallengeDecider
_DAV_METHODS = (
'OPTIONS',
'PROPFIND',
'PROPPATCH',
'MKCOL',
'LOCK',
'UNLOCK',
'TRACE',
'DELETE',
'COPY',
'MOVE'
)
_DAV_USERAGENTS = (
'Microsoft Data Access Internet Publishing Provider',
'WebDrive',
'Zope External Editor',
'WebDAVFS',
'Goliath',
'neon',
'davlib',
'wsAPI',
'Microsoft-WebDAV'
)
def default_request_classifier(environ):
""" Returns one of the classifiers 'dav', 'xmlpost', or 'browser',
depending on the imperative logic below"""
request_method = REQUEST_METHOD(environ)
if request_method in _DAV_METHODS:
return 'dav'
useragent = USER_AGENT(environ)
if useragent:
for agent in _DAV_USERAGENTS:
if useragent.find(agent) != -1:
return 'dav'
if request_method == 'POST':
if CONTENT_TYPE(environ) == 'text/xml':
return 'xmlpost'
return 'browser'
zope.interface.directlyProvides(default_request_classifier, IRequestClassifier)
def default_challenge_decider(environ, status, headers):
return status.startswith('401 ')
zope.interface.directlyProvides(default_challenge_decider, IChallengeDecider)
def passthrough_challenge_decider(environ, status, headers):
""" Don't challenge for pre-challenged responses.
o Assume responsese with 'WWW-Authenticate' or an HTML content type
are pre-challenged.
"""
if not status.startswith('401 '):
return False
h_dict = dict(headers)
if 'WWW-Authenticate' in h_dict:
return False
ct = h_dict.get('Content-Type')
if ct is not None:
return not ct.startswith('text/html')
return True
zope.interface.directlyProvides(passthrough_challenge_decider,
IChallengeDecider)