symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/urllib2.py
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-win32-2.6.1/lib/urllib2.py	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,1368 @@
+"""An extensible library for opening URLs using a variety of protocols
+
+The simplest way to use this module is to call the urlopen function,
+which accepts a string containing a URL or a Request object (described
+below).  It opens the URL and returns the results as file-like
+object; the returned object has some extra methods described below.
+
+The OpenerDirector manages a collection of Handler objects that do
+all the actual work.  Each Handler implements a particular protocol or
+option.  The OpenerDirector is a composite object that invokes the
+Handlers needed to open the requested URL.  For example, the
+HTTPHandler performs HTTP GET and POST requests and deals with
+non-error returns.  The HTTPRedirectHandler automatically deals with
+HTTP 301, 302, 303 and 307 redirect errors, and the HTTPDigestAuthHandler
+deals with digest authentication.
+
+urlopen(url, data=None) -- Basic usage is the same as original
+urllib.  pass the url and optionally data to post to an HTTP URL, and
+get a file-like object back.  One difference is that you can also pass
+a Request instance instead of URL.  Raises a URLError (subclass of
+IOError); for HTTP errors, raises an HTTPError, which can also be
+treated as a valid response.
+
+build_opener -- Function that creates a new OpenerDirector instance.
+Will install the default handlers.  Accepts one or more Handlers as
+arguments, either instances or Handler classes that it will
+instantiate.  If one of the argument is a subclass of the default
+handler, the argument will be installed instead of the default.
+
+install_opener -- Installs a new opener as the default opener.
+
+objects of interest:
+OpenerDirector --
+
+Request -- An object that encapsulates the state of a request.  The
+state can be as simple as the URL.  It can also include extra HTTP
+headers, e.g. a User-Agent.
+
+BaseHandler --
+
+exceptions:
+URLError -- A subclass of IOError, individual protocols have their own
+specific subclass.
+
+HTTPError -- Also a valid HTTP response, so you can treat an HTTP error
+as an exceptional event or valid response.
+
+internals:
+BaseHandler and parent
+_call_chain conventions
+
+Example usage:
+
+import urllib2
+
+# set up authentication info
+authinfo = urllib2.HTTPBasicAuthHandler()
+authinfo.add_password(realm='PDQ Application',
+                      uri='https://mahler:8092/site-updates.py',
+                      user='klem',
+                      passwd='geheim$parole')
+
+proxy_support = urllib2.ProxyHandler({"http" : "http://ahad-haam:3128"})
+
+# build a new opener that adds authentication and caching FTP handlers
+opener = urllib2.build_opener(proxy_support, authinfo, urllib2.CacheFTPHandler)
+
+# install it
+urllib2.install_opener(opener)
+
+f = urllib2.urlopen('http://www.python.org/')
+
+
+"""
+
+# XXX issues:
+# If an authentication error handler that tries to perform
+# authentication for some reason but fails, how should the error be
+# signalled?  The client needs to know the HTTP error code.  But if
+# the handler knows that the problem was, e.g., that it didn't know
+# that hash algo that requested in the challenge, it would be good to
+# pass that information along to the client, too.
+# ftp errors aren't handled cleanly
+# check digest against correct (i.e. non-apache) implementation
+
+# Possible extensions:
+# complex proxies  XXX not sure what exactly was meant by this
+# abstract factory for opener
+
+import base64
+import hashlib
+import httplib
+import mimetools
+import os
+import posixpath
+import random
+import re
+import socket
+import sys
+import time
+import urlparse
+import bisect
+
+try:
+    from cStringIO import StringIO
+except ImportError:
+    from StringIO import StringIO
+
+from urllib import (unwrap, unquote, splittype, splithost, quote,
+     addinfourl, splitport,
+     splitattr, ftpwrapper, splituser, splitpasswd, splitvalue)
+
+# support for FileHandler, proxies via environment variables
+from urllib import localhost, url2pathname, getproxies
+
+# used in User-Agent header sent
+__version__ = sys.version[:3]
+
+_opener = None
+def urlopen(url, data=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+    global _opener
+    if _opener is None:
+        _opener = build_opener()
+    return _opener.open(url, data, timeout)
+
+def install_opener(opener):
+    global _opener
+    _opener = opener
+
+# do these error classes make sense?
+# make sure all of the IOError stuff is overridden.  we just want to be
+# subtypes.
+
+class URLError(IOError):
+    # URLError is a sub-type of IOError, but it doesn't share any of
+    # the implementation.  need to override __init__ and __str__.
+    # It sets self.args for compatibility with other EnvironmentError
+    # subclasses, but args doesn't have the typical format with errno in
+    # slot 0 and strerror in slot 1.  This may be better than nothing.
+    def __init__(self, reason):
+        self.args = reason,
+        self.reason = reason
+
+    def __str__(self):
+        return '<urlopen error %s>' % self.reason
+
+class HTTPError(URLError, addinfourl):
+    """Raised when HTTP error occurs, but also acts like non-error return"""
+    __super_init = addinfourl.__init__
+
+    def __init__(self, url, code, msg, hdrs, fp):
+        self.code = code
+        self.msg = msg
+        self.hdrs = hdrs
+        self.fp = fp
+        self.filename = url
+        # The addinfourl classes depend on fp being a valid file
+        # object.  In some cases, the HTTPError may not have a valid
+        # file object.  If this happens, the simplest workaround is to
+        # not initialize the base classes.
+        if fp is not None:
+            self.__super_init(fp, hdrs, url, code)
+
+    def __str__(self):
+        return 'HTTP Error %s: %s' % (self.code, self.msg)
+
+# copied from cookielib.py
+_cut_port_re = re.compile(r":\d+$")
+def request_host(request):
+    """Return request-host, as defined by RFC 2965.
+
+    Variation from RFC: returned value is lowercased, for convenient
+    comparison.
+
+    """
+    url = request.get_full_url()
+    host = urlparse.urlparse(url)[1]
+    if host == "":
+        host = request.get_header("Host", "")
+
+    # remove port, if present
+    host = _cut_port_re.sub("", host, 1)
+    return host.lower()
+
+class Request:
+
+    def __init__(self, url, data=None, headers={},
+                 origin_req_host=None, unverifiable=False):
+        # unwrap('<URL:type://host/path>') --> 'type://host/path'
+        self.__original = unwrap(url)
+        self.type = None
+        # self.__r_type is what's left after doing the splittype
+        self.host = None
+        self.port = None
+        self.data = data
+        self.headers = {}
+        for key, value in headers.items():
+            self.add_header(key, value)
+        self.unredirected_hdrs = {}
+        if origin_req_host is None:
+            origin_req_host = request_host(self)
+        self.origin_req_host = origin_req_host
+        self.unverifiable = unverifiable
+
+    def __getattr__(self, attr):
+        # XXX this is a fallback mechanism to guard against these
+        # methods getting called in a non-standard order.  this may be
+        # too complicated and/or unnecessary.
+        # XXX should the __r_XXX attributes be public?
+        if attr[:12] == '_Request__r_':
+            name = attr[12:]
+            if hasattr(Request, 'get_' + name):
+                getattr(self, 'get_' + name)()
+                return getattr(self, attr)
+        raise AttributeError, attr
+
+    def get_method(self):
+        if self.has_data():
+            return "POST"
+        else:
+            return "GET"
+
+    # XXX these helper methods are lame
+
+    def add_data(self, data):
+        self.data = data
+
+    def has_data(self):
+        return self.data is not None
+
+    def get_data(self):
+        return self.data
+
+    def get_full_url(self):
+        return self.__original
+
+    def get_type(self):
+        if self.type is None:
+            self.type, self.__r_type = splittype(self.__original)
+            if self.type is None:
+                raise ValueError, "unknown url type: %s" % self.__original
+        return self.type
+
+    def get_host(self):
+        if self.host is None:
+            self.host, self.__r_host = splithost(self.__r_type)
+            if self.host:
+                self.host = unquote(self.host)
+        return self.host
+
+    def get_selector(self):
+        return self.__r_host
+
+    def set_proxy(self, host, type):
+        self.host, self.type = host, type
+        self.__r_host = self.__original
+
+    def has_proxy(self):
+        return self.__r_host == self.__original
+
+    def get_origin_req_host(self):
+        return self.origin_req_host
+
+    def is_unverifiable(self):
+        return self.unverifiable
+
+    def add_header(self, key, val):
+        # useful for something like authentication
+        self.headers[key.capitalize()] = val
+
+    def add_unredirected_header(self, key, val):
+        # will not be added to a redirected request
+        self.unredirected_hdrs[key.capitalize()] = val
+
+    def has_header(self, header_name):
+        return (header_name in self.headers or
+                header_name in self.unredirected_hdrs)
+
+    def get_header(self, header_name, default=None):
+        return self.headers.get(
+            header_name,
+            self.unredirected_hdrs.get(header_name, default))
+
+    def header_items(self):
+        hdrs = self.unredirected_hdrs.copy()
+        hdrs.update(self.headers)
+        return hdrs.items()
+
+class OpenerDirector:
+    def __init__(self):
+        client_version = "Python-urllib/%s" % __version__
+        self.addheaders = [('User-agent', client_version)]
+        # manage the individual handlers
+        self.handlers = []
+        self.handle_open = {}
+        self.handle_error = {}
+        self.process_response = {}
+        self.process_request = {}
+
+    def add_handler(self, handler):
+        if not hasattr(handler, "add_parent"):
+            raise TypeError("expected BaseHandler instance, got %r" %
+                            type(handler))
+
+        added = False
+        for meth in dir(handler):
+            if meth in ["redirect_request", "do_open", "proxy_open"]:
+                # oops, coincidental match
+                continue
+
+            i = meth.find("_")
+            protocol = meth[:i]
+            condition = meth[i+1:]
+
+            if condition.startswith("error"):
+                j = condition.find("_") + i + 1
+                kind = meth[j+1:]
+                try:
+                    kind = int(kind)
+                except ValueError:
+                    pass
+                lookup = self.handle_error.get(protocol, {})
+                self.handle_error[protocol] = lookup
+            elif condition == "open":
+                kind = protocol
+                lookup = self.handle_open
+            elif condition == "response":
+                kind = protocol
+                lookup = self.process_response
+            elif condition == "request":
+                kind = protocol
+                lookup = self.process_request
+            else:
+                continue
+
+            handlers = lookup.setdefault(kind, [])
+            if handlers:
+                bisect.insort(handlers, handler)
+            else:
+                handlers.append(handler)
+            added = True
+
+        if added:
+            # the handlers must work in an specific order, the order
+            # is specified in a Handler attribute
+            bisect.insort(self.handlers, handler)
+            handler.add_parent(self)
+
+    def close(self):
+        # Only exists for backwards compatibility.
+        pass
+
+    def _call_chain(self, chain, kind, meth_name, *args):
+        # Handlers raise an exception if no one else should try to handle
+        # the request, or return None if they can't but another handler
+        # could.  Otherwise, they return the response.
+        handlers = chain.get(kind, ())
+        for handler in handlers:
+            func = getattr(handler, meth_name)
+
+            result = func(*args)
+            if result is not None:
+                return result
+
+    def open(self, fullurl, data=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+        # accept a URL or a Request object
+        if isinstance(fullurl, basestring):
+            req = Request(fullurl, data)
+        else:
+            req = fullurl
+            if data is not None:
+                req.add_data(data)
+
+        req.timeout = timeout
+        protocol = req.get_type()
+
+        # pre-process request
+        meth_name = protocol+"_request"
+        for processor in self.process_request.get(protocol, []):
+            meth = getattr(processor, meth_name)
+            req = meth(req)
+
+        response = self._open(req, data)
+
+        # post-process response
+        meth_name = protocol+"_response"
+        for processor in self.process_response.get(protocol, []):
+            meth = getattr(processor, meth_name)
+            response = meth(req, response)
+
+        return response
+
+    def _open(self, req, data=None):
+        result = self._call_chain(self.handle_open, 'default',
+                                  'default_open', req)
+        if result:
+            return result
+
+        protocol = req.get_type()
+        result = self._call_chain(self.handle_open, protocol, protocol +
+                                  '_open', req)
+        if result:
+            return result
+
+        return self._call_chain(self.handle_open, 'unknown',
+                                'unknown_open', req)
+
+    def error(self, proto, *args):
+        if proto in ('http', 'https'):
+            # XXX http[s] protocols are special-cased
+            dict = self.handle_error['http'] # https is not different than http
+            proto = args[2]  # YUCK!
+            meth_name = 'http_error_%s' % proto
+            http_err = 1
+            orig_args = args
+        else:
+            dict = self.handle_error
+            meth_name = proto + '_error'
+            http_err = 0
+        args = (dict, proto, meth_name) + args
+        result = self._call_chain(*args)
+        if result:
+            return result
+
+        if http_err:
+            args = (dict, 'default', 'http_error_default') + orig_args
+            return self._call_chain(*args)
+
+# XXX probably also want an abstract factory that knows when it makes
+# sense to skip a superclass in favor of a subclass and when it might
+# make sense to include both
+
+def build_opener(*handlers):
+    """Create an opener object from a list of handlers.
+
+    The opener will use several default handlers, including support
+    for HTTP and FTP.
+
+    If any of the handlers passed as arguments are subclasses of the
+    default handlers, the default handlers will not be used.
+    """
+    import types
+    def isclass(obj):
+        return isinstance(obj, types.ClassType) or hasattr(obj, "__bases__")
+
+    opener = OpenerDirector()
+    default_classes = [ProxyHandler, UnknownHandler, HTTPHandler,
+                       HTTPDefaultErrorHandler, HTTPRedirectHandler,
+                       FTPHandler, FileHandler, HTTPErrorProcessor]
+    if hasattr(httplib, 'HTTPS'):
+        default_classes.append(HTTPSHandler)
+    skip = set()
+    for klass in default_classes:
+        for check in handlers:
+            if isclass(check):
+                if issubclass(check, klass):
+                    skip.add(klass)
+            elif isinstance(check, klass):
+                skip.add(klass)
+    for klass in skip:
+        default_classes.remove(klass)
+
+    for klass in default_classes:
+        opener.add_handler(klass())
+
+    for h in handlers:
+        if isclass(h):
+            h = h()
+        opener.add_handler(h)
+    return opener
+
+class BaseHandler:
+    handler_order = 500
+
+    def add_parent(self, parent):
+        self.parent = parent
+
+    def close(self):
+        # Only exists for backwards compatibility
+        pass
+
+    def __lt__(self, other):
+        if not hasattr(other, "handler_order"):
+            # Try to preserve the old behavior of having custom classes
+            # inserted after default ones (works only for custom user
+            # classes which are not aware of handler_order).
+            return True
+        return self.handler_order < other.handler_order
+
+
+class HTTPErrorProcessor(BaseHandler):
+    """Process HTTP error responses."""
+    handler_order = 1000  # after all other processing
+
+    def http_response(self, request, response):
+        code, msg, hdrs = response.code, response.msg, response.info()
+
+        # According to RFC 2616, "2xx" code indicates that the client's
+        # request was successfully received, understood, and accepted.
+        if not (200 <= code < 300):
+            response = self.parent.error(
+                'http', request, response, code, msg, hdrs)
+
+        return response
+
+    https_response = http_response
+
+class HTTPDefaultErrorHandler(BaseHandler):
+    def http_error_default(self, req, fp, code, msg, hdrs):
+        raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
+
+class HTTPRedirectHandler(BaseHandler):
+    # maximum number of redirections to any single URL
+    # this is needed because of the state that cookies introduce
+    max_repeats = 4
+    # maximum total number of redirections (regardless of URL) before
+    # assuming we're in a loop
+    max_redirections = 10
+
+    def redirect_request(self, req, fp, code, msg, headers, newurl):
+        """Return a Request or None in response to a redirect.
+
+        This is called by the http_error_30x methods when a
+        redirection response is received.  If a redirection should
+        take place, return a new Request to allow http_error_30x to
+        perform the redirect.  Otherwise, raise HTTPError if no-one
+        else should try to handle this url.  Return None if you can't
+        but another Handler might.
+        """
+        m = req.get_method()
+        if (code in (301, 302, 303, 307) and m in ("GET", "HEAD")
+            or code in (301, 302, 303) and m == "POST"):
+            # Strictly (according to RFC 2616), 301 or 302 in response
+            # to a POST MUST NOT cause a redirection without confirmation
+            # from the user (of urllib2, in this case).  In practice,
+            # essentially all clients do redirect in this case, so we
+            # do the same.
+            # be conciliant with URIs containing a space
+            newurl = newurl.replace(' ', '%20')
+            newheaders = dict((k,v) for k,v in req.headers.items()
+                              if k.lower() not in ("content-length", "content-type")
+                             )
+            return Request(newurl,
+                           headers=newheaders,
+                           origin_req_host=req.get_origin_req_host(),
+                           unverifiable=True)
+        else:
+            raise HTTPError(req.get_full_url(), code, msg, headers, fp)
+
+    # Implementation note: To avoid the server sending us into an
+    # infinite loop, the request object needs to track what URLs we
+    # have already seen.  Do this by adding a handler-specific
+    # attribute to the Request object.
+    def http_error_302(self, req, fp, code, msg, headers):
+        # Some servers (incorrectly) return multiple Location headers
+        # (so probably same goes for URI).  Use first header.
+        if 'location' in headers:
+            newurl = headers.getheaders('location')[0]
+        elif 'uri' in headers:
+            newurl = headers.getheaders('uri')[0]
+        else:
+            return
+
+        # fix a possible malformed URL
+        urlparts = urlparse.urlparse(newurl)
+        if not urlparts.path:
+            urlparts = list(urlparts)
+            urlparts[2] = "/"
+        newurl = urlparse.urlunparse(urlparts)
+
+        newurl = urlparse.urljoin(req.get_full_url(), newurl)
+
+        # XXX Probably want to forget about the state of the current
+        # request, although that might interact poorly with other
+        # handlers that also use handler-specific request attributes
+        new = self.redirect_request(req, fp, code, msg, headers, newurl)
+        if new is None:
+            return
+
+        # loop detection
+        # .redirect_dict has a key url if url was previously visited.
+        if hasattr(req, 'redirect_dict'):
+            visited = new.redirect_dict = req.redirect_dict
+            if (visited.get(newurl, 0) >= self.max_repeats or
+                len(visited) >= self.max_redirections):
+                raise HTTPError(req.get_full_url(), code,
+                                self.inf_msg + msg, headers, fp)
+        else:
+            visited = new.redirect_dict = req.redirect_dict = {}
+        visited[newurl] = visited.get(newurl, 0) + 1
+
+        # Don't close the fp until we are sure that we won't use it
+        # with HTTPError.
+        fp.read()
+        fp.close()
+
+        return self.parent.open(new)
+
+    http_error_301 = http_error_303 = http_error_307 = http_error_302
+
+    inf_msg = "The HTTP server returned a redirect error that would " \
+              "lead to an infinite loop.\n" \
+              "The last 30x error message was:\n"
+
+
+def _parse_proxy(proxy):
+    """Return (scheme, user, password, host/port) given a URL or an authority.
+
+    If a URL is supplied, it must have an authority (host:port) component.
+    According to RFC 3986, having an authority component means the URL must
+    have two slashes after the scheme:
+
+    >>> _parse_proxy('file:/ftp.example.com/')
+    Traceback (most recent call last):
+    ValueError: proxy URL with no authority: 'file:/ftp.example.com/'
+
+    The first three items of the returned tuple may be None.
+
+    Examples of authority parsing:
+
+    >>> _parse_proxy('proxy.example.com')
+    (None, None, None, 'proxy.example.com')
+    >>> _parse_proxy('proxy.example.com:3128')
+    (None, None, None, 'proxy.example.com:3128')
+
+    The authority component may optionally include userinfo (assumed to be
+    username:password):
+
+    >>> _parse_proxy('joe:password@proxy.example.com')
+    (None, 'joe', 'password', 'proxy.example.com')
+    >>> _parse_proxy('joe:password@proxy.example.com:3128')
+    (None, 'joe', 'password', 'proxy.example.com:3128')
+
+    Same examples, but with URLs instead:
+
+    >>> _parse_proxy('http://proxy.example.com/')
+    ('http', None, None, 'proxy.example.com')
+    >>> _parse_proxy('http://proxy.example.com:3128/')
+    ('http', None, None, 'proxy.example.com:3128')
+    >>> _parse_proxy('http://joe:password@proxy.example.com/')
+    ('http', 'joe', 'password', 'proxy.example.com')
+    >>> _parse_proxy('http://joe:password@proxy.example.com:3128')
+    ('http', 'joe', 'password', 'proxy.example.com:3128')
+
+    Everything after the authority is ignored:
+
+    >>> _parse_proxy('ftp://joe:password@proxy.example.com/rubbish:3128')
+    ('ftp', 'joe', 'password', 'proxy.example.com')
+
+    Test for no trailing '/' case:
+
+    >>> _parse_proxy('http://joe:password@proxy.example.com')
+    ('http', 'joe', 'password', 'proxy.example.com')
+
+    """
+    scheme, r_scheme = splittype(proxy)
+    if not r_scheme.startswith("/"):
+        # authority
+        scheme = None
+        authority = proxy
+    else:
+        # URL
+        if not r_scheme.startswith("//"):
+            raise ValueError("proxy URL with no authority: %r" % proxy)
+        # We have an authority, so for RFC 3986-compliant URLs (by ss 3.
+        # and 3.3.), path is empty or starts with '/'
+        end = r_scheme.find("/", 2)
+        if end == -1:
+            end = None
+        authority = r_scheme[2:end]
+    userinfo, hostport = splituser(authority)
+    if userinfo is not None:
+        user, password = splitpasswd(userinfo)
+    else:
+        user = password = None
+    return scheme, user, password, hostport
+
+class ProxyHandler(BaseHandler):
+    # Proxies must be in front
+    handler_order = 100
+
+    def __init__(self, proxies=None):
+        if proxies is None:
+            proxies = getproxies()
+        assert hasattr(proxies, 'has_key'), "proxies must be a mapping"
+        self.proxies = proxies
+        for type, url in proxies.items():
+            setattr(self, '%s_open' % type,
+                    lambda r, proxy=url, type=type, meth=self.proxy_open: \
+                    meth(r, proxy, type))
+
+    def proxy_open(self, req, proxy, type):
+        orig_type = req.get_type()
+        proxy_type, user, password, hostport = _parse_proxy(proxy)
+        if proxy_type is None:
+            proxy_type = orig_type
+        if user and password:
+            user_pass = '%s:%s' % (unquote(user), unquote(password))
+            creds = base64.b64encode(user_pass).strip()
+            req.add_header('Proxy-authorization', 'Basic ' + creds)
+        hostport = unquote(hostport)
+        req.set_proxy(hostport, proxy_type)
+        if orig_type == proxy_type:
+            # let other handlers take care of it
+            return None
+        else:
+            # need to start over, because the other handlers don't
+            # grok the proxy's URL type
+            # e.g. if we have a constructor arg proxies like so:
+            # {'http': 'ftp://proxy.example.com'}, we may end up turning
+            # a request for http://acme.example.com/a into one for
+            # ftp://proxy.example.com/a
+            return self.parent.open(req)
+
+class HTTPPasswordMgr:
+
+    def __init__(self):
+        self.passwd = {}
+
+    def add_password(self, realm, uri, user, passwd):
+        # uri could be a single URI or a sequence
+        if isinstance(uri, basestring):
+            uri = [uri]
+        if not realm in self.passwd:
+            self.passwd[realm] = {}
+        for default_port in True, False:
+            reduced_uri = tuple(
+                [self.reduce_uri(u, default_port) for u in uri])
+            self.passwd[realm][reduced_uri] = (user, passwd)
+
+    def find_user_password(self, realm, authuri):
+        domains = self.passwd.get(realm, {})
+        for default_port in True, False:
+            reduced_authuri = self.reduce_uri(authuri, default_port)
+            for uris, authinfo in domains.iteritems():
+                for uri in uris:
+                    if self.is_suburi(uri, reduced_authuri):
+                        return authinfo
+        return None, None
+
+    def reduce_uri(self, uri, default_port=True):
+        """Accept authority or URI and extract only the authority and path."""
+        # note HTTP URLs do not have a userinfo component
+        parts = urlparse.urlsplit(uri)
+        if parts[1]:
+            # URI
+            scheme = parts[0]
+            authority = parts[1]
+            path = parts[2] or '/'
+        else:
+            # host or host:port
+            scheme = None
+            authority = uri
+            path = '/'
+        host, port = splitport(authority)
+        if default_port and port is None and scheme is not None:
+            dport = {"http": 80,
+                     "https": 443,
+                     }.get(scheme)
+            if dport is not None:
+                authority = "%s:%d" % (host, dport)
+        return authority, path
+
+    def is_suburi(self, base, test):
+        """Check if test is below base in a URI tree
+
+        Both args must be URIs in reduced form.
+        """
+        if base == test:
+            return True
+        if base[0] != test[0]:
+            return False
+        common = posixpath.commonprefix((base[1], test[1]))
+        if len(common) == len(base[1]):
+            return True
+        return False
+
+
+class HTTPPasswordMgrWithDefaultRealm(HTTPPasswordMgr):
+
+    def find_user_password(self, realm, authuri):
+        user, password = HTTPPasswordMgr.find_user_password(self, realm,
+                                                            authuri)
+        if user is not None:
+            return user, password
+        return HTTPPasswordMgr.find_user_password(self, None, authuri)
+
+
+class AbstractBasicAuthHandler:
+
+    # XXX this allows for multiple auth-schemes, but will stupidly pick
+    # the last one with a realm specified.
+
+    # allow for double- and single-quoted realm values
+    # (single quotes are a violation of the RFC, but appear in the wild)
+    rx = re.compile('(?:.*,)*[ \t]*([^ \t]+)[ \t]+'
+                    'realm=(["\'])(.*?)\\2', re.I)
+
+    # XXX could pre-emptively send auth info already accepted (RFC 2617,
+    # end of section 2, and section 1.2 immediately after "credentials"
+    # production).
+
+    def __init__(self, password_mgr=None):
+        if password_mgr is None:
+            password_mgr = HTTPPasswordMgr()
+        self.passwd = password_mgr
+        self.add_password = self.passwd.add_password
+
+    def http_error_auth_reqed(self, authreq, host, req, headers):
+        # host may be an authority (without userinfo) or a URL with an
+        # authority
+        # XXX could be multiple headers
+        authreq = headers.get(authreq, None)
+        if authreq:
+            mo = AbstractBasicAuthHandler.rx.search(authreq)
+            if mo:
+                scheme, quote, realm = mo.groups()
+                if scheme.lower() == 'basic':
+                    return self.retry_http_basic_auth(host, req, realm)
+
+    def retry_http_basic_auth(self, host, req, realm):
+        user, pw = self.passwd.find_user_password(realm, host)
+        if pw is not None:
+            raw = "%s:%s" % (user, pw)
+            auth = 'Basic %s' % base64.b64encode(raw).strip()
+            if req.headers.get(self.auth_header, None) == auth:
+                return None
+            req.add_header(self.auth_header, auth)
+            return self.parent.open(req)
+        else:
+            return None
+
+
+class HTTPBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler):
+
+    auth_header = 'Authorization'
+
+    def http_error_401(self, req, fp, code, msg, headers):
+        url = req.get_full_url()
+        return self.http_error_auth_reqed('www-authenticate',
+                                          url, req, headers)
+
+
+class ProxyBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler):
+
+    auth_header = 'Proxy-authorization'
+
+    def http_error_407(self, req, fp, code, msg, headers):
+        # http_error_auth_reqed requires that there is no userinfo component in
+        # authority.  Assume there isn't one, since urllib2 does not (and
+        # should not, RFC 3986 s. 3.2.1) support requests for URLs containing
+        # userinfo.
+        authority = req.get_host()
+        return self.http_error_auth_reqed('proxy-authenticate',
+                                          authority, req, headers)
+
+
+def randombytes(n):
+    """Return n random bytes."""
+    # Use /dev/urandom if it is available.  Fall back to random module
+    # if not.  It might be worthwhile to extend this function to use
+    # other platform-specific mechanisms for getting random bytes.
+    if os.path.exists("/dev/urandom"):
+        f = open("/dev/urandom")
+        s = f.read(n)
+        f.close()
+        return s
+    else:
+        L = [chr(random.randrange(0, 256)) for i in range(n)]
+        return "".join(L)
+
+class AbstractDigestAuthHandler:
+    # Digest authentication is specified in RFC 2617.
+
+    # XXX The client does not inspect the Authentication-Info header
+    # in a successful response.
+
+    # XXX It should be possible to test this implementation against
+    # a mock server that just generates a static set of challenges.
+
+    # XXX qop="auth-int" supports is shaky
+
+    def __init__(self, passwd=None):
+        if passwd is None:
+            passwd = HTTPPasswordMgr()
+        self.passwd = passwd
+        self.add_password = self.passwd.add_password
+        self.retried = 0
+        self.nonce_count = 0
+
+    def reset_retry_count(self):
+        self.retried = 0
+
+    def http_error_auth_reqed(self, auth_header, host, req, headers):
+        authreq = headers.get(auth_header, None)
+        if self.retried > 5:
+            # Don't fail endlessly - if we failed once, we'll probably
+            # fail a second time. Hm. Unless the Password Manager is
+            # prompting for the information. Crap. This isn't great
+            # but it's better than the current 'repeat until recursion
+            # depth exceeded' approach <wink>
+            raise HTTPError(req.get_full_url(), 401, "digest auth failed",
+                            headers, None)
+        else:
+            self.retried += 1
+        if authreq:
+            scheme = authreq.split()[0]
+            if scheme.lower() == 'digest':
+                return self.retry_http_digest_auth(req, authreq)
+
+    def retry_http_digest_auth(self, req, auth):
+        token, challenge = auth.split(' ', 1)
+        chal = parse_keqv_list(parse_http_list(challenge))
+        auth = self.get_authorization(req, chal)
+        if auth:
+            auth_val = 'Digest %s' % auth
+            if req.headers.get(self.auth_header, None) == auth_val:
+                return None
+            req.add_unredirected_header(self.auth_header, auth_val)
+            resp = self.parent.open(req)
+            return resp
+
+    def get_cnonce(self, nonce):
+        # The cnonce-value is an opaque
+        # quoted string value provided by the client and used by both client
+        # and server to avoid chosen plaintext attacks, to provide mutual
+        # authentication, and to provide some message integrity protection.
+        # This isn't a fabulous effort, but it's probably Good Enough.
+        dig = hashlib.sha1("%s:%s:%s:%s" % (self.nonce_count, nonce, time.ctime(),
+                                            randombytes(8))).hexdigest()
+        return dig[:16]
+
+    def get_authorization(self, req, chal):
+        try:
+            realm = chal['realm']
+            nonce = chal['nonce']
+            qop = chal.get('qop')
+            algorithm = chal.get('algorithm', 'MD5')
+            # mod_digest doesn't send an opaque, even though it isn't
+            # supposed to be optional
+            opaque = chal.get('opaque', None)
+        except KeyError:
+            return None
+
+        H, KD = self.get_algorithm_impls(algorithm)
+        if H is None:
+            return None
+
+        user, pw = self.passwd.find_user_password(realm, req.get_full_url())
+        if user is None:
+            return None
+
+        # XXX not implemented yet
+        if req.has_data():
+            entdig = self.get_entity_digest(req.get_data(), chal)
+        else:
+            entdig = None
+
+        A1 = "%s:%s:%s" % (user, realm, pw)
+        A2 = "%s:%s" % (req.get_method(),
+                        # XXX selector: what about proxies and full urls
+                        req.get_selector())
+        if qop == 'auth':
+            self.nonce_count += 1
+            ncvalue = '%08x' % self.nonce_count
+            cnonce = self.get_cnonce(nonce)
+            noncebit = "%s:%s:%s:%s:%s" % (nonce, ncvalue, cnonce, qop, H(A2))
+            respdig = KD(H(A1), noncebit)
+        elif qop is None:
+            respdig = KD(H(A1), "%s:%s" % (nonce, H(A2)))
+        else:
+            # XXX handle auth-int.
+            raise URLError("qop '%s' is not supported." % qop)
+
+        # XXX should the partial digests be encoded too?
+
+        base = 'username="%s", realm="%s", nonce="%s", uri="%s", ' \
+               'response="%s"' % (user, realm, nonce, req.get_selector(),
+                                  respdig)
+        if opaque:
+            base += ', opaque="%s"' % opaque
+        if entdig:
+            base += ', digest="%s"' % entdig
+        base += ', algorithm="%s"' % algorithm
+        if qop:
+            base += ', qop=auth, nc=%s, cnonce="%s"' % (ncvalue, cnonce)
+        return base
+
+    def get_algorithm_impls(self, algorithm):
+        # algorithm should be case-insensitive according to RFC2617
+        algorithm = algorithm.upper()
+        # lambdas assume digest modules are imported at the top level
+        if algorithm == 'MD5':
+            H = lambda x: hashlib.md5(x).hexdigest()
+        elif algorithm == 'SHA':
+            H = lambda x: hashlib.sha1(x).hexdigest()
+        # XXX MD5-sess
+        KD = lambda s, d: H("%s:%s" % (s, d))
+        return H, KD
+
+    def get_entity_digest(self, data, chal):
+        # XXX not implemented yet
+        return None
+
+
+class HTTPDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
+    """An authentication protocol defined by RFC 2069
+
+    Digest authentication improves on basic authentication because it
+    does not transmit passwords in the clear.
+    """
+
+    auth_header = 'Authorization'
+    handler_order = 490  # before Basic auth
+
+    def http_error_401(self, req, fp, code, msg, headers):
+        host = urlparse.urlparse(req.get_full_url())[1]
+        retry = self.http_error_auth_reqed('www-authenticate',
+                                           host, req, headers)
+        self.reset_retry_count()
+        return retry
+
+
+class ProxyDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
+
+    auth_header = 'Proxy-Authorization'
+    handler_order = 490  # before Basic auth
+
+    def http_error_407(self, req, fp, code, msg, headers):
+        host = req.get_host()
+        retry = self.http_error_auth_reqed('proxy-authenticate',
+                                           host, req, headers)
+        self.reset_retry_count()
+        return retry
+
+class AbstractHTTPHandler(BaseHandler):
+
+    def __init__(self, debuglevel=0):
+        self._debuglevel = debuglevel
+
+    def set_http_debuglevel(self, level):
+        self._debuglevel = level
+
+    def do_request_(self, request):
+        host = request.get_host()
+        if not host:
+            raise URLError('no host given')
+
+        if request.has_data():  # POST
+            data = request.get_data()
+            if not request.has_header('Content-type'):
+                request.add_unredirected_header(
+                    'Content-type',
+                    'application/x-www-form-urlencoded')
+            if not request.has_header('Content-length'):
+                request.add_unredirected_header(
+                    'Content-length', '%d' % len(data))
+
+        sel_host = host
+        if request.has_proxy():
+            scheme, sel = splittype(request.get_selector())
+            sel_host, sel_path = splithost(sel)
+
+        if not request.has_header('Host'):
+            request.add_unredirected_header('Host', sel_host)
+        for name, value in self.parent.addheaders:
+            name = name.capitalize()
+            if not request.has_header(name):
+                request.add_unredirected_header(name, value)
+
+        return request
+
+    def do_open(self, http_class, req):
+        """Return an addinfourl object for the request, using http_class.
+
+        http_class must implement the HTTPConnection API from httplib.
+        The addinfourl return value is a file-like object.  It also
+        has methods and attributes including:
+            - info(): return a mimetools.Message object for the headers
+            - geturl(): return the original request URL
+            - code: HTTP status code
+        """
+        host = req.get_host()
+        if not host:
+            raise URLError('no host given')
+
+        h = http_class(host, timeout=req.timeout) # will parse host:port
+        h.set_debuglevel(self._debuglevel)
+
+        headers = dict(req.headers)
+        headers.update(req.unredirected_hdrs)
+        # We want to make an HTTP/1.1 request, but the addinfourl
+        # class isn't prepared to deal with a persistent connection.
+        # It will try to read all remaining data from the socket,
+        # which will block while the server waits for the next request.
+        # So make sure the connection gets closed after the (only)
+        # request.
+        headers["Connection"] = "close"
+        headers = dict(
+            (name.title(), val) for name, val in headers.items())
+        try:
+            h.request(req.get_method(), req.get_selector(), req.data, headers)
+            r = h.getresponse()
+        except socket.error, err: # XXX what error?
+            raise URLError(err)
+
+        # Pick apart the HTTPResponse object to get the addinfourl
+        # object initialized properly.
+
+        # Wrap the HTTPResponse object in socket's file object adapter
+        # for Windows.  That adapter calls recv(), so delegate recv()
+        # to read().  This weird wrapping allows the returned object to
+        # have readline() and readlines() methods.
+
+        # XXX It might be better to extract the read buffering code
+        # out of socket._fileobject() and into a base class.
+
+        r.recv = r.read
+        fp = socket._fileobject(r, close=True)
+
+        resp = addinfourl(fp, r.msg, req.get_full_url())
+        resp.code = r.status
+        resp.msg = r.reason
+        return resp
+
+
+class HTTPHandler(AbstractHTTPHandler):
+
+    def http_open(self, req):
+        return self.do_open(httplib.HTTPConnection, req)
+
+    http_request = AbstractHTTPHandler.do_request_
+
+if hasattr(httplib, 'HTTPS'):
+    class HTTPSHandler(AbstractHTTPHandler):
+
+        def https_open(self, req):
+            return self.do_open(httplib.HTTPSConnection, req)
+
+        https_request = AbstractHTTPHandler.do_request_
+
+class HTTPCookieProcessor(BaseHandler):
+    def __init__(self, cookiejar=None):
+        import cookielib
+        if cookiejar is None:
+            cookiejar = cookielib.CookieJar()
+        self.cookiejar = cookiejar
+
+    def http_request(self, request):
+        self.cookiejar.add_cookie_header(request)
+        return request
+
+    def http_response(self, request, response):
+        self.cookiejar.extract_cookies(response, request)
+        return response
+
+    https_request = http_request
+    https_response = http_response
+
+class UnknownHandler(BaseHandler):
+    def unknown_open(self, req):
+        type = req.get_type()
+        raise URLError('unknown url type: %s' % type)
+
+def parse_keqv_list(l):
+    """Parse list of key=value strings where keys are not duplicated."""
+    parsed = {}
+    for elt in l:
+        k, v = elt.split('=', 1)
+        if v[0] == '"' and v[-1] == '"':
+            v = v[1:-1]
+        parsed[k] = v
+    return parsed
+
+def parse_http_list(s):
+    """Parse lists as described by RFC 2068 Section 2.
+
+    In particular, parse comma-separated lists where the elements of
+    the list may include quoted-strings.  A quoted-string could
+    contain a comma.  A non-quoted string could have quotes in the
+    middle.  Neither commas nor quotes count if they are escaped.
+    Only double-quotes count, not single-quotes.
+    """
+    res = []
+    part = ''
+
+    escape = quote = False
+    for cur in s:
+        if escape:
+            part += cur
+            escape = False
+            continue
+        if quote:
+            if cur == '\\':
+                escape = True
+                continue
+            elif cur == '"':
+                quote = False
+            part += cur
+            continue
+
+        if cur == ',':
+            res.append(part)
+            part = ''
+            continue
+
+        if cur == '"':
+            quote = True
+
+        part += cur
+
+    # append last part
+    if part:
+        res.append(part)
+
+    return [part.strip() for part in res]
+
+class FileHandler(BaseHandler):
+    # Use local file or FTP depending on form of URL
+    def file_open(self, req):
+        url = req.get_selector()
+        if url[:2] == '//' and url[2:3] != '/':
+            req.type = 'ftp'
+            return self.parent.open(req)
+        else:
+            return self.open_local_file(req)
+
+    # names for the localhost
+    names = None
+    def get_names(self):
+        if FileHandler.names is None:
+            try:
+                FileHandler.names = (socket.gethostbyname('localhost'),
+                                    socket.gethostbyname(socket.gethostname()))
+            except socket.gaierror:
+                FileHandler.names = (socket.gethostbyname('localhost'),)
+        return FileHandler.names
+
+    # not entirely sure what the rules are here
+    def open_local_file(self, req):
+        import email.utils
+        import mimetypes
+        host = req.get_host()
+        file = req.get_selector()
+        localfile = url2pathname(file)
+        try:
+            stats = os.stat(localfile)
+            size = stats.st_size
+            modified = email.utils.formatdate(stats.st_mtime, usegmt=True)
+            mtype = mimetypes.guess_type(file)[0]
+            headers = mimetools.Message(StringIO(
+                'Content-type: %s\nContent-length: %d\nLast-modified: %s\n' %
+                (mtype or 'text/plain', size, modified)))
+            if host:
+                host, port = splitport(host)
+            if not host or \
+                (not port and socket.gethostbyname(host) in self.get_names()):
+                return addinfourl(open(localfile, 'rb'),
+                                  headers, 'file:'+file)
+        except OSError, msg:
+            # urllib2 users shouldn't expect OSErrors coming from urlopen()
+            raise URLError(msg)
+        raise URLError('file not on local host')
+
+class FTPHandler(BaseHandler):
+    def ftp_open(self, req):
+        import ftplib
+        import mimetypes
+        host = req.get_host()
+        if not host:
+            raise URLError('ftp error: no host given')
+        host, port = splitport(host)
+        if port is None:
+            port = ftplib.FTP_PORT
+        else:
+            port = int(port)
+
+        # username/password handling
+        user, host = splituser(host)
+        if user:
+            user, passwd = splitpasswd(user)
+        else:
+            passwd = None
+        host = unquote(host)
+        user = unquote(user or '')
+        passwd = unquote(passwd or '')
+
+        try:
+            host = socket.gethostbyname(host)
+        except socket.error, msg:
+            raise URLError(msg)
+        path, attrs = splitattr(req.get_selector())
+        dirs = path.split('/')
+        dirs = map(unquote, dirs)
+        dirs, file = dirs[:-1], dirs[-1]
+        if dirs and not dirs[0]:
+            dirs = dirs[1:]
+        try:
+            fw = self.connect_ftp(user, passwd, host, port, dirs, req.timeout)
+            type = file and 'I' or 'D'
+            for attr in attrs:
+                attr, value = splitvalue(attr)
+                if attr.lower() == 'type' and \
+                   value in ('a', 'A', 'i', 'I', 'd', 'D'):
+                    type = value.upper()
+            fp, retrlen = fw.retrfile(file, type)
+            headers = ""
+            mtype = mimetypes.guess_type(req.get_full_url())[0]
+            if mtype:
+                headers += "Content-type: %s\n" % mtype
+            if retrlen is not None and retrlen >= 0:
+                headers += "Content-length: %d\n" % retrlen
+            sf = StringIO(headers)
+            headers = mimetools.Message(sf)
+            return addinfourl(fp, headers, req.get_full_url())
+        except ftplib.all_errors, msg:
+            raise URLError, ('ftp error: %s' % msg), sys.exc_info()[2]
+
+    def connect_ftp(self, user, passwd, host, port, dirs, timeout):
+        fw = ftpwrapper(user, passwd, host, port, dirs, timeout)
+##        fw.ftp.set_debuglevel(1)
+        return fw
+
+class CacheFTPHandler(FTPHandler):
+    # XXX would be nice to have pluggable cache strategies
+    # XXX this stuff is definitely not thread safe
+    def __init__(self):
+        self.cache = {}
+        self.timeout = {}
+        self.soonest = 0
+        self.delay = 60
+        self.max_conns = 16
+
+    def setTimeout(self, t):
+        self.delay = t
+
+    def setMaxConns(self, m):
+        self.max_conns = m
+
+    def connect_ftp(self, user, passwd, host, port, dirs, timeout):
+        key = user, host, port, '/'.join(dirs), timeout
+        if key in self.cache:
+            self.timeout[key] = time.time() + self.delay
+        else:
+            self.cache[key] = ftpwrapper(user, passwd, host, port, dirs, timeout)
+            self.timeout[key] = time.time() + self.delay
+        self.check_cache()
+        return self.cache[key]
+
+    def check_cache(self):
+        # first check for old ones
+        t = time.time()
+        if self.soonest <= t:
+            for k, v in self.timeout.items():
+                if v < t:
+                    self.cache[k].close()
+                    del self.cache[k]
+                    del self.timeout[k]
+        self.soonest = min(self.timeout.values())
+
+        # then check the size
+        if len(self.cache) == self.max_conns:
+            for k, v in self.timeout.items():
+                if v == self.soonest:
+                    del self.cache[k]
+                    del self.timeout[k]
+                    break
+            self.soonest = min(self.timeout.values())