Redirect to an error page when a GAE exception occurs
Patch by: Sverre Rabbelier
import os
import re
from Cookie import SimpleCookie, CookieError
from pprint import pformat
from urllib import urlencode
from urlparse import urljoin
try:
# The mod_python version is more efficient, so try importing it first.
from mod_python.util import parse_qsl
except ImportError:
from cgi import parse_qsl
from django.utils.datastructures import MultiValueDict, ImmutableList
from django.utils.encoding import smart_str, iri_to_uri, force_unicode
from django.http.multipartparser import MultiPartParser
from django.conf import settings
from django.core.files import uploadhandler
from utils import *
RESERVED_CHARS="!*'();:@&=+$,/?%#[]"
absolute_http_url_re = re.compile(r"^https?://", re.I)
class Http404(Exception):
pass
class HttpRequest(object):
"""A basic HTTP request."""
# The encoding used in GET/POST dicts. None means use default setting.
_encoding = None
_upload_handlers = []
def __init__(self):
self.GET, self.POST, self.COOKIES, self.META, self.FILES = {}, {}, {}, {}, {}
self.path = ''
self.path_info = ''
self.method = None
def __repr__(self):
return '<HttpRequest\nGET:%s,\nPOST:%s,\nCOOKIES:%s,\nMETA:%s>' % \
(pformat(self.GET), pformat(self.POST), pformat(self.COOKIES),
pformat(self.META))
def get_host(self):
"""Returns the HTTP host using the environment or request headers."""
# We try three options, in order of decreasing preference.
if 'HTTP_X_FORWARDED_HOST' in self.META:
host = self.META['HTTP_X_FORWARDED_HOST']
elif 'HTTP_HOST' in self.META:
host = self.META['HTTP_HOST']
else:
# Reconstruct the host using the algorithm from PEP 333.
host = self.META['SERVER_NAME']
server_port = str(self.META['SERVER_PORT'])
if server_port != (self.is_secure() and '443' or '80'):
host = '%s:%s' % (host, server_port)
return host
def get_full_path(self):
return ''
def build_absolute_uri(self, location=None):
"""
Builds an absolute URI from the location and the variables available in
this request. If no location is specified, the absolute URI is built on
``request.get_full_path()``.
"""
if not location:
location = self.get_full_path()
if not absolute_http_url_re.match(location):
current_uri = '%s://%s%s' % (self.is_secure() and 'https' or 'http',
self.get_host(), self.path)
location = urljoin(current_uri, location)
return location
def is_secure(self):
return os.environ.get("HTTPS") == "on"
def is_ajax(self):
return self.META.get('HTTP_X_REQUESTED_WITH') == 'XMLHttpRequest'
def _set_encoding(self, val):
"""
Sets the encoding used for GET/POST accesses. If the GET or POST
dictionary has already been created, it is removed and recreated on the
next access (so that it is decoded correctly).
"""
self._encoding = val
if hasattr(self, '_get'):
del self._get
if hasattr(self, '_post'):
del self._post
def _get_encoding(self):
return self._encoding
encoding = property(_get_encoding, _set_encoding)
def _initialize_handlers(self):
self._upload_handlers = [uploadhandler.load_handler(handler, self)
for handler in settings.FILE_UPLOAD_HANDLERS]
def _set_upload_handlers(self, upload_handlers):
if hasattr(self, '_files'):
raise AttributeError("You cannot set the upload handlers after the upload has been processed.")
self._upload_handlers = upload_handlers
def _get_upload_handlers(self):
if not self._upload_handlers:
# If thre are no upload handlers defined, initialize them from settings.
self._initialize_handlers()
return self._upload_handlers
upload_handlers = property(_get_upload_handlers, _set_upload_handlers)
def parse_file_upload(self, META, post_data):
"""Returns a tuple of (POST QueryDict, FILES MultiValueDict)."""
self.upload_handlers = ImmutableList(
self.upload_handlers,
warning = "You cannot alter upload handlers after the upload has been processed."
)
parser = MultiPartParser(META, post_data, self.upload_handlers, self.encoding)
return parser.parse()
class QueryDict(MultiValueDict):
"""
A specialized MultiValueDict that takes a query string when initialized.
This is immutable unless you create a copy of it.
Values retrieved from this class are converted from the given encoding
(DEFAULT_CHARSET by default) to unicode.
"""
# These are both reset in __init__, but is specified here at the class
# level so that unpickling will have valid values
_mutable = True
_encoding = None
def __init__(self, query_string, mutable=False, encoding=None):
MultiValueDict.__init__(self)
if not encoding:
# *Important*: do not import settings any earlier because of note
# in core.handlers.modpython.
from django.conf import settings
encoding = settings.DEFAULT_CHARSET
self.encoding = encoding
for key, value in parse_qsl((query_string or ''), True): # keep_blank_values=True
self.appendlist(force_unicode(key, encoding, errors='replace'),
force_unicode(value, encoding, errors='replace'))
self._mutable = mutable
def _get_encoding(self):
if self._encoding is None:
# *Important*: do not import settings at the module level because
# of the note in core.handlers.modpython.
from django.conf import settings
self._encoding = settings.DEFAULT_CHARSET
return self._encoding
def _set_encoding(self, value):
self._encoding = value
encoding = property(_get_encoding, _set_encoding)
def _assert_mutable(self):
if not self._mutable:
raise AttributeError("This QueryDict instance is immutable")
def __setitem__(self, key, value):
self._assert_mutable()
key = str_to_unicode(key, self.encoding)
value = str_to_unicode(value, self.encoding)
MultiValueDict.__setitem__(self, key, value)
def __delitem__(self, key):
self._assert_mutable()
super(QueryDict, self).__delitem__(key)
def __copy__(self):
result = self.__class__('', mutable=True)
for key, value in dict.items(self):
dict.__setitem__(result, key, value)
return result
def __deepcopy__(self, memo):
import copy
result = self.__class__('', mutable=True)
memo[id(self)] = result
for key, value in dict.items(self):
dict.__setitem__(result, copy.deepcopy(key, memo), copy.deepcopy(value, memo))
return result
def setlist(self, key, list_):
self._assert_mutable()
key = str_to_unicode(key, self.encoding)
list_ = [str_to_unicode(elt, self.encoding) for elt in list_]
MultiValueDict.setlist(self, key, list_)
def setlistdefault(self, key, default_list=()):
self._assert_mutable()
if key not in self:
self.setlist(key, default_list)
return MultiValueDict.getlist(self, key)
def appendlist(self, key, value):
self._assert_mutable()
key = str_to_unicode(key, self.encoding)
value = str_to_unicode(value, self.encoding)
MultiValueDict.appendlist(self, key, value)
def update(self, other_dict):
self._assert_mutable()
f = lambda s: str_to_unicode(s, self.encoding)
if hasattr(other_dict, 'lists'):
for key, valuelist in other_dict.lists():
for value in valuelist:
MultiValueDict.update(self, {f(key): f(value)})
else:
d = dict([(f(k), f(v)) for k, v in other_dict.items()])
MultiValueDict.update(self, d)
def pop(self, key, *args):
self._assert_mutable()
return MultiValueDict.pop(self, key, *args)
def popitem(self):
self._assert_mutable()
return MultiValueDict.popitem(self)
def clear(self):
self._assert_mutable()
MultiValueDict.clear(self)
def setdefault(self, key, default=None):
self._assert_mutable()
key = str_to_unicode(key, self.encoding)
default = str_to_unicode(default, self.encoding)
return MultiValueDict.setdefault(self, key, default)
def copy(self):
"""Returns a mutable copy of this object."""
return self.__deepcopy__({})
def urlencode(self):
output = []
for k, list_ in self.lists():
k = smart_str(k, self.encoding)
output.extend([urlencode({k: smart_str(v, self.encoding)}) for v in list_])
return '&'.join(output)
def parse_cookie(cookie):
if cookie == '':
return {}
try:
c = SimpleCookie()
c.load(cookie)
except CookieError:
# Invalid cookie
return {}
cookiedict = {}
for key in c.keys():
cookiedict[key] = c.get(key).value
return cookiedict
class HttpResponse(object):
"""A basic HTTP response, with content and dictionary-accessed headers."""
status_code = 200
def __init__(self, content='', mimetype=None, status=None,
content_type=None):
from django.conf import settings
self._charset = settings.DEFAULT_CHARSET
if mimetype:
content_type = mimetype # For backwards compatibility
if not content_type:
content_type = "%s; charset=%s" % (settings.DEFAULT_CONTENT_TYPE,
settings.DEFAULT_CHARSET)
if not isinstance(content, basestring) and hasattr(content, '__iter__'):
self._container = content
self._is_string = False
else:
self._container = [content]
self._is_string = True
self.cookies = SimpleCookie()
if status:
self.status_code = status
# _headers is a mapping of the lower-case name to the original case of
# the header (required for working with legacy systems) and the header
# value.
self._headers = {'content-type': ('Content-Type', content_type)}
def __str__(self):
"""Full HTTP message, including headers."""
return '\n'.join(['%s: %s' % (key, value)
for key, value in self._headers.values()]) \
+ '\n\n' + self.content
def _convert_to_ascii(self, *values):
"""Converts all values to ascii strings."""
for value in values:
if isinstance(value, unicode):
try:
yield value.encode('us-ascii')
except UnicodeError, e:
e.reason += ', HTTP response headers must be in US-ASCII format'
raise
else:
yield str(value)
def __setitem__(self, header, value):
header, value = self._convert_to_ascii(header, value)
self._headers[header.lower()] = (header, value)
def __delitem__(self, header):
try:
del self._headers[header.lower()]
except KeyError:
pass
def __getitem__(self, header):
return self._headers[header.lower()][1]
def has_header(self, header):
"""Case-insensitive check for a header."""
return self._headers.has_key(header.lower())
__contains__ = has_header
def items(self):
return self._headers.values()
def get(self, header, alternate):
return self._headers.get(header.lower(), (None, alternate))[1]
def set_cookie(self, key, value='', max_age=None, expires=None, path='/',
domain=None, secure=False):
self.cookies[key] = value
if max_age is not None:
self.cookies[key]['max-age'] = max_age
if expires is not None:
self.cookies[key]['expires'] = expires
if path is not None:
self.cookies[key]['path'] = path
if domain is not None:
self.cookies[key]['domain'] = domain
if secure:
self.cookies[key]['secure'] = True
def delete_cookie(self, key, path='/', domain=None):
self.set_cookie(key, max_age=0, path=path, domain=domain,
expires='Thu, 01-Jan-1970 00:00:00 GMT')
def _get_content(self):
if self.has_header('Content-Encoding'):
return ''.join(self._container)
return smart_str(''.join(self._container), self._charset)
def _set_content(self, value):
self._container = [value]
self._is_string = True
content = property(_get_content, _set_content)
def __iter__(self):
self._iterator = iter(self._container)
return self
def next(self):
chunk = self._iterator.next()
if isinstance(chunk, unicode):
chunk = chunk.encode(self._charset)
return str(chunk)
def close(self):
if hasattr(self._container, 'close'):
self._container.close()
# The remaining methods partially implement the file-like object interface.
# See http://docs.python.org/lib/bltin-file-objects.html
def write(self, content):
if not self._is_string:
raise Exception("This %s instance is not writable" % self.__class__)
self._container.append(content)
def flush(self):
pass
def tell(self):
if not self._is_string:
raise Exception("This %s instance cannot tell its position" % self.__class__)
return sum([len(chunk) for chunk in self._container])
class HttpResponseRedirect(HttpResponse):
status_code = 302
def __init__(self, redirect_to):
HttpResponse.__init__(self)
self['Location'] = iri_to_uri(redirect_to)
class HttpResponsePermanentRedirect(HttpResponse):
status_code = 301
def __init__(self, redirect_to):
HttpResponse.__init__(self)
self['Location'] = iri_to_uri(redirect_to)
class HttpResponseNotModified(HttpResponse):
status_code = 304
class HttpResponseBadRequest(HttpResponse):
status_code = 400
class HttpResponseNotFound(HttpResponse):
status_code = 404
class HttpResponseForbidden(HttpResponse):
status_code = 403
class HttpResponseNotAllowed(HttpResponse):
status_code = 405
def __init__(self, permitted_methods):
HttpResponse.__init__(self)
self['Allow'] = ', '.join(permitted_methods)
class HttpResponseGone(HttpResponse):
status_code = 410
def __init__(self, *args, **kwargs):
HttpResponse.__init__(self, *args, **kwargs)
class HttpResponseServerError(HttpResponse):
status_code = 500
def __init__(self, *args, **kwargs):
HttpResponse.__init__(self, *args, **kwargs)
# A backwards compatible alias for HttpRequest.get_host.
def get_host(request):
return request.get_host()
# It's neither necessary nor appropriate to use
# django.utils.encoding.smart_unicode for parsing URLs and form inputs. Thus,
# this slightly more restricted function.
def str_to_unicode(s, encoding):
"""
Converts basestring objects to unicode, using the given encoding. Illegally
encoded input characters are replaced with Unicode "unknown" codepoint
(\ufffd).
Returns any non-basestring objects without change.
"""
if isinstance(s, str):
return unicode(s, encoding, 'replace')
else:
return s