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livetrax/tools/bug_tool/ClientCookie/_urllib2_support.py

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"""Integration with Python standard library module urllib2.
Also includes a redirection bugfix, support for parsing HTML HEAD blocks for
the META HTTP-EQUIV tag contents, and following Refresh header redirects.
Copyright 2002-2003 John J Lee <jjl@pobox.com>
This code is free software; you can redistribute it and/or modify it under
the terms of the BSD License (see the file COPYING included with the
distribution).
"""
import copy, time
import ClientCookie
from _ClientCookie import CookieJar, request_host
from _Util import isstringlike
from _Debug import _debug
try: True
except NameError:
True = 1
False = 0
CHUNK = 1024 # size of chunks fed to HTML HEAD parser, in bytes
try:
from urllib2 import AbstractHTTPHandler
except ImportError:
pass
else:
import urlparse, urllib2, urllib, httplib, htmllib, formatter, string
from urllib2 import URLError, HTTPError
import types, string, socket
from cStringIO import StringIO
from _Util import seek_wrapper
try:
import threading
_threading = threading; del threading
except ImportError:
import dummy_threading
_threading = dummy_threading; del dummy_threading
# This fixes a bug in urllib2 as of Python 2.1.3 and 2.2.2
# (http://www.python.org/sf/549151)
# 2.2.3 is broken here (my fault!), 2.3 is fixed.
class HTTPRedirectHandler(urllib2.BaseHandler):
# maximum number of redirections before assuming we're in a loop
max_redirections = 10
# Implementation notes:
# 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. The value
# of the dict is used to count the number of times the same url has
# been visited. This is needed because this isn't necessarily a loop:
# there is more than one way to redirect (Refresh, 302, 303, 307).
# Another handler-specific Request attribute, original_url, is used to
# remember the URL of the original request so that it is possible to
# decide whether or not RFC 2965 cookies should be turned on during
# redirect.
# Always unhandled redirection codes:
# 300 Multiple Choices: should not handle this here.
# 304 Not Modified: no need to handle here: only of interest to caches
# that do conditional GETs
# 305 Use Proxy: probably not worth dealing with here
# 306 Unused: what was this for in the previous versions of protocol??
def redirect_request(self, newurl, req, fp, code, msg, headers):
"""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, return None to indicate that an HTTPError should be
raised.
"""
if code in (301, 302, 303) or (code == 307 and not req.has_data()):
# 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.
return Request(newurl, headers=req.headers)
else:
raise HTTPError(req.get_full_url(), code, msg, headers, fp)
def http_error_302(self, req, fp, code, msg, headers):
if headers.has_key('location'):
newurl = headers['location']
elif headers.has_key('uri'):
newurl = headers['uri']
else:
return
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(newurl, req, fp, code, msg, headers)
if new is None:
return
# remember where we started from
if hasattr(req, "original_url"):
new.original_url = req.original_url
else:
new.original_url = req.get_full_url()
# loop detection
# .error_302_dict[(url, code)] is number of times url
# previously visited as a result of a redirection with this
# code (error_30x_dict would be a better name).
new.origin_req_host = req.origin_req_host
if not hasattr(req, 'error_302_dict'):
new.error_302_dict = req.error_302_dict = {(newurl, code): 1}
else:
ed = new.error_302_dict = req.error_302_dict
nr_visits = ed.get((newurl, code), 0)
# Refreshes generate fake 302s, so we can hit the same URL as
# a result of the same redirection code twice without
# necessarily being in a loop! So, allow two visits to each
# URL as a result of each redirection code.
if len(ed) < self.max_redirections and nr_visits < 2:
ed[(newurl, code)] = nr_visits + 1
else:
raise HTTPError(req.get_full_url(), code,
self.inf_msg + msg, headers, fp)
if ClientCookie.REDIRECT_DEBUG:
_debug("redirecting to %s", newurl)
# 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"
class Request(urllib2.Request):
def __init__(self, url, data=None, headers={}):
urllib2.Request.__init__(self, url, data, headers)
self.unredirected_hdrs = {}
def add_unredirected_header(self, key, val):
# these headers do not persist from one request to the next in a chain
# of requests
self.unredirected_hdrs[string.capitalize(key)] = val
def has_key(self, header_name):
if (self.headers.has_key(header_name) or
self.unredirected_hdrs.has_key(header_name)):
return True
return False
def get(self, header_name, failobj=None):
if self.headers.has_key(header_name):
return self.headers[header_name]
if self.unredirected_headers.has_key(header_name):
return self.unredirected_headers[header_name]
return failobj
class BaseProcessor:
processor_order = 500
def add_parent(self, parent):
self.parent = parent
def close(self):
self.parent = None
def __lt__(self, other):
if not hasattr(other, "processor_order"):
return True
return self.processor_order < other.processor_order
class HTTPRequestUpgradeProcessor(BaseProcessor):
# upgrade Request to class with support for headers that don't get
# redirected
processor_order = 0 # before anything else
def http_request(self, request):
if not hasattr(request, "add_unredirected_header"):
request = Request(request._Request__original, request.data,
request.headers)
return request
https_request = http_request
class HTTPEquivProcessor(BaseProcessor):
"""Append META HTTP-EQUIV headers to regular HTTP headers."""
def http_response(self, request, response):
if not hasattr(response, "seek"):
response = seek_wrapper(response)
# grab HTTP-EQUIV headers and add them to the true HTTP headers
headers = response.info()
for hdr, val in parse_head(response):
headers[hdr] = val
response.seek(0)
return response
https_response = http_response
# XXX ATM this only takes notice of http responses -- probably
# should be independent of protocol scheme (http, ftp, etc.)
class SeekableProcessor(BaseProcessor):
"""Make responses seekable."""
def http_response(self, request, response):
if not hasattr(response, "seek"):
return seek_wrapper(response)
return response
https_response = http_response
# XXX if this gets added to urllib2, unverifiable would end up as an
# attribute on Request.
class HTTPCookieProcessor(BaseProcessor):
"""Handle HTTP cookies."""
def __init__(self, cookies=None):
if cookies is None:
cookies = CookieJar()
self.cookies = cookies
def _unverifiable(self, request):
if hasattr(request, "error_302_dict") and request.error_302_dict:
redirect = True
else:
redirect = False
if (redirect or
(hasattr(request, "unverifiable") and request.unverifiable)):
unverifiable = True
else:
unverifiable = False
return unverifiable
def http_request(self, request):
unverifiable = self._unverifiable(request)
if not unverifiable:
# Stuff request-host of this origin transaction into Request
# object, because we need to know it to know whether cookies
# should be in operation during derived requests (redirects,
# specifically -- including refreshes).
request.origin_req_host = request_host(request)
self.cookies.add_cookie_header(request, unverifiable)
return request
def http_response(self, request, response):
unverifiable = self._unverifiable(request)
self.cookies.extract_cookies(response, request, unverifiable)
return response
https_request = http_request
https_response = http_response
class HTTPRefererProcessor(BaseProcessor):
"""Add Referer header to requests.
This only makes sense if you use each RefererProcessor for a single
chain of requests only (so, for example, if you use a single
HTTPRefererProcessor to fetch a series of URLs extracted from a single
page, this will break).
"""
def __init__(self):
self.referer = None
def http_request(self, request):
if ((self.referer is not None) and
not request.has_key("Referer")):
request.add_unredirected_header("Referer", self.referer)
return request
def http_response(self, request, response):
self.referer = response.geturl()
return response
https_request = http_request
https_response = http_response
class HTTPStandardHeadersProcessor(BaseProcessor):
def http_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_key('Content-type'):
request.add_unredirected_header(
'Content-type',
'application/x-www-form-urlencoded')
if not request.has_key('Content-length'):
request.add_unredirected_header(
'Content-length', '%d' % len(data))
scheme, sel = urllib.splittype(request.get_selector())
sel_host, sel_path = urllib.splithost(sel)
if not request.has_key('Host'):
request.add_unredirected_header('Host', sel_host or host)
for name, value in self.parent.addheaders:
name = string.capitalize(name)
if not request.has_key(name):
request.add_unredirected_header(name, value)
return request
https_request = http_request
class HTTPResponseDebugProcessor(BaseProcessor):
processor_order = 900 # before redirections, after everything else
def http_response(self, request, response):
if not hasattr(response, "seek"):
response = seek_wrapper(response)
_debug(response.read())
_debug("*****************************************************")
response.seek(0)
return response
https_response = http_response
class HTTPRefreshProcessor(BaseProcessor):
"""Perform HTTP Refresh redirections.
Note that if a non-200 HTTP code has occurred (for example, a 30x
redirect), this processor will do nothing.
By default, only zero-time Refresh headers are redirected. Use the
max_time constructor argument to allow Refresh with longer pauses.
Use the honor_time argument to control whether the requested pause
is honoured (with a time.sleep()) or skipped in favour of immediate
redirection.
"""
processor_order = 1000
def __init__(self, max_time=0, honor_time=True):
self.max_time = max_time
self.honor_time = honor_time
def http_response(self, request, response):
code, msg, hdrs = response.code, response.msg, response.info()
if code == 200 and hdrs.has_key("refresh"):
refresh = hdrs["refresh"]
i = string.find(refresh, ";")
if i != -1:
pause, newurl_spec = refresh[:i], refresh[i+1:]
i = string.find(newurl_spec, "=")
if i != -1:
pause = int(pause)
if pause <= self.max_time:
if pause != 0 and self.honor_time:
time.sleep(pause)
newurl = newurl_spec[i+1:]
# fake a 302 response
hdrs["location"] = newurl
response = self.parent.error(
'http', request, response, 302, msg, hdrs)
return response
https_response = http_response
class HTTPErrorProcessor(BaseProcessor):
"""Process non-200 HTTP error responses.
This just passes the job on to the Handler.<proto>_error_<code>
methods, via the OpenerDirector.error method.
"""
processor_order = 1000
def http_response(self, request, response):
code, msg, hdrs = response.code, response.msg, response.info()
if code != 200:
response = self.parent.error(
'http', request, response, code, msg, hdrs)
return response
https_response = http_response
class OpenerDirector(urllib2.OpenerDirector):
# XXX might be useful to have remove_processor, too (say you want to
# set a new RefererProcessor, but keep the old CookieProcessor --
# could always just create everything anew, though (using old
# CookieJar object to create CookieProcessor)
def __init__(self):
urllib2.OpenerDirector.__init__(self)
#self.processors = []
self.process_response = {}
self.process_request = {}
def add_handler(self, handler):
# XXX
# tidy me
# the same handler could be added twice without detection
added = 0
for meth in dir(handler.__class__):
if meth[-5:] == '_open':
protocol = meth[:-5]
if self.handle_open.has_key(protocol):
self.handle_open[protocol].append(handler)
self.handle_open[protocol].sort()
else:
self.handle_open[protocol] = [handler]
added = 1
continue
i = string.find(meth, '_')
j = string.find(meth[i+1:], '_') + i + 1
if j != -1 and meth[i+1:j] == 'error':
proto = meth[:i]
kind = meth[j+1:]
try:
kind = int(kind)
except ValueError:
pass
dict = self.handle_error.get(proto, {})
if dict.has_key(kind):
dict[kind].append(handler)
dict[kind].sort()
else:
dict[kind] = [handler]
self.handle_error[proto] = dict
added = 1
continue
if meth[-9:] == "_response":
protocol = meth[:-9]
if self.process_response.has_key(protocol):
self.process_response[protocol].append(handler)
self.process_response[protocol].sort()
else:
self.process_response[protocol] = [handler]
added = True
continue
elif meth[-8:] == "_request":
protocol = meth[:-8]
if self.process_request.has_key(protocol):
self.process_request[protocol].append(handler)
self.process_request[protocol].sort()
else:
self.process_request[protocol] = [handler]
added = True
continue
if added:
self.handlers.append(handler)
self.handlers.sort()
handler.add_parent(self)
## def add_processor(self, processor):
## added = False
## for meth in dir(processor):
## if meth[-9:] == "_response":
## protocol = meth[:-9]
## if self.process_response.has_key(protocol):
## self.process_response[protocol].append(processor)
## self.process_response[protocol].sort()
## else:
## self.process_response[protocol] = [processor]
## added = True
## continue
## elif meth[-8:] == "_request":
## protocol = meth[:-8]
## if self.process_request.has_key(protocol):
## self.process_request[protocol].append(processor)
## self.process_request[protocol].sort()
## else:
## self.process_request[protocol] = [processor]
## added = True
## continue
## if added:
## self.processors.append(processor)
## # XXX base class sorts .handlers, but I have no idea why
## #self.processors.sort()
## processor.add_parent(self)
def _request(self, url_or_req, data):
if isstringlike(url_or_req):
req = Request(url_or_req, data)
else:
# already a urllib2.Request instance
req = url_or_req
if data is not None:
req.add_data(data)
return req
def open(self, fullurl, data=None):
req = self._request(fullurl, data)
type = req.get_type()
# pre-process request
# XXX should we allow a Processor to change the type (URL
# scheme) of the request?
meth_name = type+"_request"
for processor in self.process_request.get(type, []):
meth = getattr(processor, meth_name)
req = meth(req)
response = urllib2.OpenerDirector.open(self, req, data)
# post-process response
meth_name = type+"_response"
for processor in self.process_response.get(type, []):
meth = getattr(processor, meth_name)
response = meth(req, response)
return response
## def close(self):
## urllib2.OpenerDirector.close(self)
## for processor in self.processors:
## processor.close()
## self.processors = []
# Note the absence of redirect and header-adding code here
# (AbstractHTTPHandler), and the lack of other clutter that would be
# here without Processors.
class AbstractHTTPHandler(urllib2.BaseHandler):
def do_open(self, http_class, req):
host = req.get_host()
if not host:
raise URLError('no host given')
h = http_class(host) # will parse host:port
if ClientCookie.HTTP_DEBUG:
h.set_debuglevel(1)
if req.has_data():
h.putrequest('POST', req.get_selector())
else:
h.putrequest('GET', req.get_selector())
for k, v in req.headers.items():
h.putheader(k, v)
for k, v in req.unredirected_hdrs.items():
h.putheader(k, v)
# httplib will attempt to connect() here. be prepared
# to convert a socket error to a URLError.
try:
h.endheaders()
except socket.error, err:
raise URLError(err)
if req.has_data():
h.send(req.get_data())
code, msg, hdrs = h.getreply()
fp = h.getfile()
response = urllib.addinfourl(fp, hdrs, req.get_full_url())
response.code = code
response.msg = msg
return response
# XXX would self.reset() work, instead of raising this exception?
class EndOfHeadError(Exception): pass
class HeadParser(htmllib.HTMLParser):
# only these elements are allowed in or before HEAD of document
head_elems = ("html", "head",
"title", "base",
"script", "style", "meta", "link", "object")
def __init__(self):
htmllib.HTMLParser.__init__(self, formatter.NullFormatter())
self.http_equiv = []
def start_meta(self, attrs):
http_equiv = content = None
for key, value in attrs:
if key == "http-equiv":
http_equiv = value
elif key == "content":
content = value
if http_equiv is not None:
self.http_equiv.append((http_equiv, content))
def handle_starttag(self, tag, method, attrs):
if tag in self.head_elems:
method(attrs)
else:
raise EndOfHeadError()
def handle_endtag(self, tag, method):
if tag in self.head_elems:
method()
else:
raise EndOfHeadError()
def end_head(self):
raise EndOfHeadError()
def parse_head(file):
"""Return a list of key, value pairs."""
hp = HeadParser()
while 1:
data = file.read(CHUNK)
try:
hp.feed(data)
except EndOfHeadError:
break
if len(data) != CHUNK:
# this should only happen if there is no HTML body, or if
# CHUNK is big
break
return hp.http_equiv
class HTTPHandler(AbstractHTTPHandler):
def http_open(self, req):
return self.do_open(httplib.HTTP, req)
if hasattr(httplib, 'HTTPS'):
class HTTPSHandler(AbstractHTTPHandler):
def https_open(self, req):
return self.do_open(httplib.HTTPS, req)
def build_opener(*handlers):
"""Create an opener object from a list of handlers and processors.
The opener will use several default handlers and processors, including
support for HTTP and FTP. If there is a ProxyHandler, it must be at the
front of the list of handlers. (Yuck. This is fixed in 2.3.)
If any of the handlers passed as arguments are subclasses of the
default handlers, the default handlers will not be used.
"""
opener = OpenerDirector()
default_classes = [
# handlers
urllib2.ProxyHandler,
urllib2.UnknownHandler,
HTTPHandler, # from this module (derived from new AbstractHTTPHandler)
urllib2.HTTPDefaultErrorHandler,
HTTPRedirectHandler, # from this module (bugfixed)
urllib2.FTPHandler,
urllib2.FileHandler,
# processors
HTTPRequestUpgradeProcessor,
#HTTPEquivProcessor,
#SeekableProcessor,
HTTPCookieProcessor,
#HTTPRefererProcessor,
HTTPStandardHeadersProcessor,
#HTTPRefreshProcessor,
HTTPErrorProcessor
]
if hasattr(httplib, 'HTTPS'):
default_classes.append(HTTPSHandler)
skip = []
for klass in default_classes:
for check in handlers:
if type(check) == types.ClassType:
if issubclass(check, klass):
skip.append(klass)
elif type(check) == types.InstanceType:
if isinstance(check, klass):
skip.append(klass)
for klass in skip:
default_classes.remove(klass)
to_add = []
for klass in default_classes:
to_add.append(klass())
for h in handlers:
if type(h) == types.ClassType:
h = h()
to_add.append(h)
for instance in to_add:
opener.add_handler(instance)
## # yuck
## if hasattr(instance, "processor_order"):
## opener.add_processor(instance)
## else:
## opener.add_handler(instance)
return opener
_opener = None
urlopen_lock = _threading.Lock()
def urlopen(url, data=None):
global _opener
if _opener is None:
urlopen_lock.acquire()
try:
if _opener is None:
_opener = build_opener()
finally:
urlopen_lock.release()
return _opener.open(url, data)
def install_opener(opener):
global _opener
_opener = opener