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django/django/core/urlresolvers.py
Claude Paroz e167e96cfe Fixed #22223 -- Prevented over-escaping URLs in reverse()
And follow more closely the class of characters defined in the
RFC 3986.
Thanks Erik van Zijst for the report and the initial patch, and
Tim Graham for the review.
2014-07-09 09:54:34 +02:00

628 lines
23 KiB
Python

"""
This module converts requested URLs to callback view functions.
RegexURLResolver is the main class here. Its resolve() method takes a URL (as
a string) and returns a tuple in this format:
(view_function, function_args, function_kwargs)
"""
from __future__ import unicode_literals
import functools
from importlib import import_module
import re
from threading import local
import warnings
from django.http import Http404
from django.core.exceptions import ImproperlyConfigured, ViewDoesNotExist
from django.utils.datastructures import MultiValueDict
from django.utils.deprecation import RemovedInDjango20Warning
from django.utils.encoding import force_str, force_text, iri_to_uri
from django.utils.functional import lazy
from django.utils.http import RFC3986_SUBDELIMS, urlquote
from django.utils.module_loading import module_has_submodule
from django.utils.regex_helper import normalize
from django.utils import six, lru_cache
from django.utils.translation import get_language
# SCRIPT_NAME prefixes for each thread are stored here. If there's no entry for
# the current thread (which is the only one we ever access), it is assumed to
# be empty.
_prefixes = local()
# Overridden URLconfs for each thread are stored here.
_urlconfs = local()
class ResolverMatch(object):
def __init__(self, func, args, kwargs, url_name=None, app_name=None, namespaces=None):
self.func = func
self.args = args
self.kwargs = kwargs
self.url_name = url_name
self.app_name = app_name
if namespaces:
self.namespaces = [x for x in namespaces if x]
else:
self.namespaces = []
self.namespace = ':'.join(self.namespaces)
if not hasattr(func, '__name__'):
# A class-based view
self._func_path = '.'.join([func.__class__.__module__, func.__class__.__name__])
else:
# A function-based view
self._func_path = '.'.join([func.__module__, func.__name__])
view_path = url_name or self._func_path
self.view_name = ':'.join(self.namespaces + [view_path])
def __getitem__(self, index):
return (self.func, self.args, self.kwargs)[index]
def __repr__(self):
return "ResolverMatch(func=%s, args=%s, kwargs=%s, url_name=%s, app_name=%s, namespaces=%s)" % (
self._func_path, self.args, self.kwargs, self.url_name, self.app_name, self.namespaces)
class Resolver404(Http404):
pass
class NoReverseMatch(Exception):
pass
@lru_cache.lru_cache(maxsize=None)
def get_callable(lookup_view, can_fail=False):
"""
Return a callable corresponding to lookup_view. This function is used
by both resolve() and reverse(), so can_fail allows the caller to choose
between returning the input as is and raising an exception when the input
string can't be interpreted as an import path.
If lookup_view is already a callable, return it.
If lookup_view is a string import path that can be resolved to a callable,
import that callable and return it.
If lookup_view is some other kind of string and can_fail is True, the string
is returned as is. If can_fail is False, an exception is raised (either
ImportError or ViewDoesNotExist).
"""
if callable(lookup_view):
return lookup_view
mod_name, func_name = get_mod_func(lookup_view)
if not func_name: # No '.' in lookup_view
if can_fail:
return lookup_view
else:
raise ImportError(
"Could not import '%s'. The path must be fully qualified." %
lookup_view)
try:
mod = import_module(mod_name)
except ImportError:
if can_fail:
return lookup_view
else:
parentmod, submod = get_mod_func(mod_name)
if submod and not module_has_submodule(import_module(parentmod), submod):
raise ViewDoesNotExist(
"Could not import '%s'. Parent module %s does not exist." %
(lookup_view, mod_name))
else:
raise
else:
try:
view_func = getattr(mod, func_name)
except AttributeError:
if can_fail:
return lookup_view
else:
raise ViewDoesNotExist(
"Could not import '%s'. View does not exist in module %s." %
(lookup_view, mod_name))
else:
if not callable(view_func):
# For backwards compatibility this is raised regardless of can_fail
raise ViewDoesNotExist(
"Could not import '%s.%s'. View is not callable." %
(mod_name, func_name))
return view_func
@lru_cache.lru_cache(maxsize=None)
def get_resolver(urlconf):
if urlconf is None:
from django.conf import settings
urlconf = settings.ROOT_URLCONF
return RegexURLResolver(r'^/', urlconf)
@lru_cache.lru_cache(maxsize=None)
def get_ns_resolver(ns_pattern, resolver):
# Build a namespaced resolver for the given parent urlconf pattern.
# This makes it possible to have captured parameters in the parent
# urlconf pattern.
ns_resolver = RegexURLResolver(ns_pattern, resolver.url_patterns)
return RegexURLResolver(r'^/', [ns_resolver])
def get_mod_func(callback):
# Converts 'django.views.news.stories.story_detail' to
# ['django.views.news.stories', 'story_detail']
try:
dot = callback.rindex('.')
except ValueError:
return callback, ''
return callback[:dot], callback[dot + 1:]
class LocaleRegexProvider(object):
"""
A mixin to provide a default regex property which can vary by active
language.
"""
def __init__(self, regex):
# regex is either a string representing a regular expression, or a
# translatable string (using ugettext_lazy) representing a regular
# expression.
self._regex = regex
self._regex_dict = {}
@property
def regex(self):
"""
Returns a compiled regular expression, depending upon the activated
language-code.
"""
language_code = get_language()
if language_code not in self._regex_dict:
if isinstance(self._regex, six.string_types):
regex = self._regex
else:
regex = force_text(self._regex)
try:
compiled_regex = re.compile(regex, re.UNICODE)
except re.error as e:
raise ImproperlyConfigured(
'"%s" is not a valid regular expression: %s' %
(regex, six.text_type(e)))
self._regex_dict[language_code] = compiled_regex
return self._regex_dict[language_code]
class RegexURLPattern(LocaleRegexProvider):
def __init__(self, regex, callback, default_args=None, name=None):
LocaleRegexProvider.__init__(self, regex)
# callback is either a string like 'foo.views.news.stories.story_detail'
# which represents the path to a module and a view function name, or a
# callable object (view).
if callable(callback):
self._callback = callback
else:
self._callback = None
self._callback_str = callback
self.default_args = default_args or {}
self.name = name
def __repr__(self):
return force_str('<%s %s %s>' % (self.__class__.__name__, self.name, self.regex.pattern))
def add_prefix(self, prefix):
"""
Adds the prefix string to a string-based callback.
"""
if not prefix or not hasattr(self, '_callback_str'):
return
self._callback_str = prefix + '.' + self._callback_str
def resolve(self, path):
match = self.regex.search(path)
if match:
# If there are any named groups, use those as kwargs, ignoring
# non-named groups. Otherwise, pass all non-named arguments as
# positional arguments.
kwargs = match.groupdict()
if kwargs:
args = ()
else:
args = match.groups()
# In both cases, pass any extra_kwargs as **kwargs.
kwargs.update(self.default_args)
return ResolverMatch(self.callback, args, kwargs, self.name)
@property
def callback(self):
if self._callback is not None:
return self._callback
self._callback = get_callable(self._callback_str)
return self._callback
class RegexURLResolver(LocaleRegexProvider):
def __init__(self, regex, urlconf_name, default_kwargs=None, app_name=None, namespace=None):
LocaleRegexProvider.__init__(self, regex)
# urlconf_name is a string representing the module containing URLconfs.
self.urlconf_name = urlconf_name
if not isinstance(urlconf_name, six.string_types):
self._urlconf_module = self.urlconf_name
self.callback = None
self.default_kwargs = default_kwargs or {}
self.namespace = namespace
self.app_name = app_name
self._reverse_dict = {}
self._namespace_dict = {}
self._app_dict = {}
# set of dotted paths to all functions and classes that are used in
# urlpatterns
self._callback_strs = set()
self._populated = False
def __repr__(self):
if isinstance(self.urlconf_name, list) and len(self.urlconf_name):
# Don't bother to output the whole list, it can be huge
urlconf_repr = '<%s list>' % self.urlconf_name[0].__class__.__name__
else:
urlconf_repr = repr(self.urlconf_name)
return str('<%s %s (%s:%s) %s>') % (
self.__class__.__name__, urlconf_repr, self.app_name,
self.namespace, self.regex.pattern)
def _populate(self):
lookups = MultiValueDict()
namespaces = {}
apps = {}
language_code = get_language()
for pattern in reversed(self.url_patterns):
if hasattr(pattern, '_callback_str'):
self._callback_strs.add(pattern._callback_str)
elif hasattr(pattern, '_callback'):
callback = pattern._callback
if isinstance(callback, functools.partial):
callback = callback.func
if not hasattr(callback, '__name__'):
lookup_str = callback.__module__ + "." + callback.__class__.__name__
else:
lookup_str = callback.__module__ + "." + callback.__name__
self._callback_strs.add(lookup_str)
p_pattern = pattern.regex.pattern
if p_pattern.startswith('^'):
p_pattern = p_pattern[1:]
if isinstance(pattern, RegexURLResolver):
if pattern.namespace:
namespaces[pattern.namespace] = (p_pattern, pattern)
if pattern.app_name:
apps.setdefault(pattern.app_name, []).append(pattern.namespace)
else:
parent_pat = pattern.regex.pattern
for name in pattern.reverse_dict:
for matches, pat, defaults in pattern.reverse_dict.getlist(name):
new_matches = normalize(parent_pat + pat)
lookups.appendlist(name, (new_matches, p_pattern + pat, dict(defaults, **pattern.default_kwargs)))
for namespace, (prefix, sub_pattern) in pattern.namespace_dict.items():
namespaces[namespace] = (p_pattern + prefix, sub_pattern)
for app_name, namespace_list in pattern.app_dict.items():
apps.setdefault(app_name, []).extend(namespace_list)
self._callback_strs.update(pattern._callback_strs)
else:
bits = normalize(p_pattern)
lookups.appendlist(pattern.callback, (bits, p_pattern, pattern.default_args))
if pattern.name is not None:
lookups.appendlist(pattern.name, (bits, p_pattern, pattern.default_args))
self._reverse_dict[language_code] = lookups
self._namespace_dict[language_code] = namespaces
self._app_dict[language_code] = apps
self._populated = True
@property
def reverse_dict(self):
language_code = get_language()
if language_code not in self._reverse_dict:
self._populate()
return self._reverse_dict[language_code]
@property
def namespace_dict(self):
language_code = get_language()
if language_code not in self._namespace_dict:
self._populate()
return self._namespace_dict[language_code]
@property
def app_dict(self):
language_code = get_language()
if language_code not in self._app_dict:
self._populate()
return self._app_dict[language_code]
def resolve(self, path):
path = force_text(path) # path may be a reverse_lazy object
tried = []
match = self.regex.search(path)
if match:
new_path = path[match.end():]
for pattern in self.url_patterns:
try:
sub_match = pattern.resolve(new_path)
except Resolver404 as e:
sub_tried = e.args[0].get('tried')
if sub_tried is not None:
tried.extend([pattern] + t for t in sub_tried)
else:
tried.append([pattern])
else:
if sub_match:
sub_match_dict = dict(match.groupdict(), **self.default_kwargs)
sub_match_dict.update(sub_match.kwargs)
return ResolverMatch(sub_match.func, sub_match.args, sub_match_dict, sub_match.url_name, self.app_name or sub_match.app_name, [self.namespace] + sub_match.namespaces)
tried.append([pattern])
raise Resolver404({'tried': tried, 'path': new_path})
raise Resolver404({'path': path})
@property
def urlconf_module(self):
try:
return self._urlconf_module
except AttributeError:
self._urlconf_module = import_module(self.urlconf_name)
return self._urlconf_module
@property
def url_patterns(self):
# urlconf_module might be a valid set of patterns, so we default to it
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
try:
iter(patterns)
except TypeError:
msg = (
"The included urlconf '{name}' does not appear to have any "
"patterns in it. If you see valid patterns in the file then "
"the issue is probably caused by a circular import."
)
raise ImproperlyConfigured(msg.format(name=self.urlconf_name))
return patterns
def resolve_error_handler(self, view_type):
callback = getattr(self.urlconf_module, 'handler%s' % view_type, None)
if not callback:
# No handler specified in file; use default
# Lazy import, since django.urls imports this file
from django.conf import urls
callback = getattr(urls, 'handler%s' % view_type)
return get_callable(callback), {}
def reverse(self, lookup_view, *args, **kwargs):
return self._reverse_with_prefix(lookup_view, '', *args, **kwargs)
def _reverse_with_prefix(self, lookup_view, _prefix, *args, **kwargs):
if args and kwargs:
raise ValueError("Don't mix *args and **kwargs in call to reverse()!")
text_args = [force_text(v) for v in args]
text_kwargs = dict((k, force_text(v)) for (k, v) in kwargs.items())
if not self._populated:
self._populate()
original_lookup = lookup_view
try:
if lookup_view in self._callback_strs:
lookup_view = get_callable(lookup_view, True)
except (ImportError, AttributeError) as e:
raise NoReverseMatch("Error importing '%s': %s." % (lookup_view, e))
else:
if not callable(original_lookup) and callable(lookup_view):
warnings.warn(
'Reversing by dotted path is deprecated (%s).' % original_lookup,
RemovedInDjango20Warning, stacklevel=3
)
possibilities = self.reverse_dict.getlist(lookup_view)
prefix_norm, prefix_args = normalize(urlquote(_prefix))[0]
for possibility, pattern, defaults in possibilities:
for result, params in possibility:
if args:
if len(args) != len(params) + len(prefix_args):
continue
candidate_subs = dict(zip(prefix_args + params, text_args))
else:
if set(kwargs.keys()) | set(defaults.keys()) != set(params) | set(defaults.keys()) | set(prefix_args):
continue
matches = True
for k, v in defaults.items():
if kwargs.get(k, v) != v:
matches = False
break
if not matches:
continue
candidate_subs = text_kwargs
# WSGI provides decoded URLs, without %xx escapes, and the URL
# resolver operates on such URLs. First substitute arguments
# without quoting to build a decoded URL and look for a match.
# Then, if we have a match, redo the substitution with quoted
# arguments in order to return a properly encoded URL.
candidate_pat = prefix_norm.replace('%', '%%') + result
if re.search('^%s%s' % (prefix_norm, pattern), candidate_pat % candidate_subs, re.UNICODE):
# safe characters from `pchar` definition of RFC 3986
candidate_subs = dict((k, urlquote(v, safe=RFC3986_SUBDELIMS + str('/~:@')))
for (k, v) in candidate_subs.items())
return candidate_pat % candidate_subs
# lookup_view can be URL label, or dotted path, or callable, Any of
# these can be passed in at the top, but callables are not friendly in
# error messages.
m = getattr(lookup_view, '__module__', None)
n = getattr(lookup_view, '__name__', None)
if m is not None and n is not None:
lookup_view_s = "%s.%s" % (m, n)
else:
lookup_view_s = lookup_view
patterns = [pattern for (possibility, pattern, defaults) in possibilities]
raise NoReverseMatch("Reverse for '%s' with arguments '%s' and keyword "
"arguments '%s' not found. %d pattern(s) tried: %s" %
(lookup_view_s, args, kwargs, len(patterns), patterns))
class LocaleRegexURLResolver(RegexURLResolver):
"""
A URL resolver that always matches the active language code as URL prefix.
Rather than taking a regex argument, we just override the ``regex``
function to always return the active language-code as regex.
"""
def __init__(self, urlconf_name, default_kwargs=None, app_name=None, namespace=None):
super(LocaleRegexURLResolver, self).__init__(
None, urlconf_name, default_kwargs, app_name, namespace)
@property
def regex(self):
language_code = get_language()
if language_code not in self._regex_dict:
regex_compiled = re.compile('^%s/' % language_code, re.UNICODE)
self._regex_dict[language_code] = regex_compiled
return self._regex_dict[language_code]
def resolve(path, urlconf=None):
if urlconf is None:
urlconf = get_urlconf()
return get_resolver(urlconf).resolve(path)
def reverse(viewname, urlconf=None, args=None, kwargs=None, prefix=None, current_app=None):
if urlconf is None:
urlconf = get_urlconf()
resolver = get_resolver(urlconf)
args = args or []
kwargs = kwargs or {}
if prefix is None:
prefix = get_script_prefix()
if not isinstance(viewname, six.string_types):
view = viewname
else:
parts = viewname.split(':')
parts.reverse()
view = parts[0]
path = parts[1:]
resolved_path = []
ns_pattern = ''
while path:
ns = path.pop()
# Lookup the name to see if it could be an app identifier
try:
app_list = resolver.app_dict[ns]
# Yes! Path part matches an app in the current Resolver
if current_app and current_app in app_list:
# If we are reversing for a particular app,
# use that namespace
ns = current_app
elif ns not in app_list:
# The name isn't shared by one of the instances
# (i.e., the default) so just pick the first instance
# as the default.
ns = app_list[0]
except KeyError:
pass
try:
extra, resolver = resolver.namespace_dict[ns]
resolved_path.append(ns)
ns_pattern = ns_pattern + extra
except KeyError as key:
if resolved_path:
raise NoReverseMatch(
"%s is not a registered namespace inside '%s'" %
(key, ':'.join(resolved_path)))
else:
raise NoReverseMatch("%s is not a registered namespace" %
key)
if ns_pattern:
resolver = get_ns_resolver(ns_pattern, resolver)
return iri_to_uri(resolver._reverse_with_prefix(view, prefix, *args, **kwargs))
reverse_lazy = lazy(reverse, str)
def clear_url_caches():
get_callable.cache_clear()
get_resolver.cache_clear()
get_ns_resolver.cache_clear()
def set_script_prefix(prefix):
"""
Sets the script prefix for the current thread.
"""
if not prefix.endswith('/'):
prefix += '/'
_prefixes.value = prefix
def get_script_prefix():
"""
Returns the currently active script prefix. Useful for client code that
wishes to construct their own URLs manually (although accessing the request
instance is normally going to be a lot cleaner).
"""
return getattr(_prefixes, "value", '/')
def clear_script_prefix():
"""
Unsets the script prefix for the current thread.
"""
try:
del _prefixes.value
except AttributeError:
pass
def set_urlconf(urlconf_name):
"""
Sets the URLconf for the current thread (overriding the default one in
settings). Set to None to revert back to the default.
"""
if urlconf_name:
_urlconfs.value = urlconf_name
else:
if hasattr(_urlconfs, "value"):
del _urlconfs.value
def get_urlconf(default=None):
"""
Returns the root URLconf to use for the current thread if it has been
changed from the default one.
"""
return getattr(_urlconfs, "value", default)
def is_valid_path(path, urlconf=None):
"""
Returns True if the given path resolves against the default URL resolver,
False otherwise.
This is a convenience method to make working with "is this a match?" cases
easier, avoiding unnecessarily indented try...except blocks.
"""
try:
resolve(path, urlconf)
return True
except Resolver404:
return False