--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/django/core/urlresolvers.py Wed Jan 20 00:34:04 2010 +0100
@@ -0,0 +1,373 @@
+"""
+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)
+"""
+
+import re
+
+from django.http import Http404
+from django.core.exceptions import ImproperlyConfigured, ViewDoesNotExist
+from django.utils.datastructures import MultiValueDict
+from django.utils.encoding import iri_to_uri, force_unicode, smart_str
+from django.utils.functional import memoize
+from django.utils.importlib import import_module
+from django.utils.regex_helper import normalize
+from django.utils.thread_support import currentThread
+
+try:
+ reversed
+except NameError:
+ from django.utils.itercompat import reversed # Python 2.3 fallback
+ from sets import Set as set
+
+_resolver_cache = {} # Maps URLconf modules to RegexURLResolver instances.
+_callable_cache = {} # Maps view and url pattern names to their view functions.
+
+# 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 = {}
+
+class Resolver404(Http404):
+ pass
+
+class NoReverseMatch(Exception):
+ # Don't make this raise an error when used in a template.
+ silent_variable_failure = True
+
+def get_callable(lookup_view, can_fail=False):
+ """
+ Convert a string version of a function name to the callable object.
+
+ If the lookup_view is not an import path, it is assumed to be a URL pattern
+ label and the original string is returned.
+
+ If can_fail is True, lookup_view might be a URL pattern label, so errors
+ during the import fail and the string is returned.
+ """
+ if not callable(lookup_view):
+ try:
+ # Bail early for non-ASCII strings (they can't be functions).
+ lookup_view = lookup_view.encode('ascii')
+ mod_name, func_name = get_mod_func(lookup_view)
+ if func_name != '':
+ lookup_view = getattr(import_module(mod_name), func_name)
+ if not callable(lookup_view):
+ raise AttributeError("'%s.%s' is not a callable." % (mod_name, func_name))
+ except (ImportError, AttributeError):
+ if not can_fail:
+ raise
+ except UnicodeEncodeError:
+ pass
+ return lookup_view
+get_callable = memoize(get_callable, _callable_cache, 1)
+
+def get_resolver(urlconf):
+ if urlconf is None:
+ from django.conf import settings
+ urlconf = settings.ROOT_URLCONF
+ return RegexURLResolver(r'^/', urlconf)
+get_resolver = memoize(get_resolver, _resolver_cache, 1)
+
+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 RegexURLPattern(object):
+ def __init__(self, regex, callback, default_args=None, name=None):
+ # regex is a string representing a regular expression.
+ # 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).
+ self.regex = re.compile(regex, re.UNICODE)
+ 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 '<%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 self.callback, args, kwargs
+
+ def _get_callback(self):
+ if self._callback is not None:
+ return self._callback
+ try:
+ self._callback = get_callable(self._callback_str)
+ except ImportError, e:
+ mod_name, _ = get_mod_func(self._callback_str)
+ raise ViewDoesNotExist, "Could not import %s. Error was: %s" % (mod_name, str(e))
+ except AttributeError, e:
+ mod_name, func_name = get_mod_func(self._callback_str)
+ raise ViewDoesNotExist, "Tried %s in module %s. Error was: %s" % (func_name, mod_name, str(e))
+ return self._callback
+ callback = property(_get_callback)
+
+class RegexURLResolver(object):
+ def __init__(self, regex, urlconf_name, default_kwargs=None, app_name=None, namespace=None):
+ # regex is a string representing a regular expression.
+ # urlconf_name is a string representing the module containing URLconfs.
+ self.regex = re.compile(regex, re.UNICODE)
+ self.urlconf_name = urlconf_name
+ if not isinstance(urlconf_name, basestring):
+ 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 = None
+ self._namespace_dict = None
+ self._app_dict = None
+
+ def __repr__(self):
+ return '<%s %s (%s:%s) %s>' % (self.__class__.__name__, self.urlconf_name, self.app_name, self.namespace, self.regex.pattern)
+
+ def _populate(self):
+ lookups = MultiValueDict()
+ namespaces = {}
+ apps = {}
+ for pattern in reversed(self.url_patterns):
+ 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 = normalize(pattern.regex.pattern)
+ for name in pattern.reverse_dict:
+ for matches, pat in pattern.reverse_dict.getlist(name):
+ new_matches = []
+ for piece, p_args in parent:
+ new_matches.extend([(piece + suffix, p_args + args) for (suffix, args) in matches])
+ lookups.appendlist(name, (new_matches, p_pattern + pat))
+ 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)
+ else:
+ bits = normalize(p_pattern)
+ lookups.appendlist(pattern.callback, (bits, p_pattern))
+ lookups.appendlist(pattern.name, (bits, p_pattern))
+ self._reverse_dict = lookups
+ self._namespace_dict = namespaces
+ self._app_dict = apps
+
+ def _get_reverse_dict(self):
+ if self._reverse_dict is None:
+ self._populate()
+ return self._reverse_dict
+ reverse_dict = property(_get_reverse_dict)
+
+ def _get_namespace_dict(self):
+ if self._namespace_dict is None:
+ self._populate()
+ return self._namespace_dict
+ namespace_dict = property(_get_namespace_dict)
+
+ def _get_app_dict(self):
+ if self._app_dict is None:
+ self._populate()
+ return self._app_dict
+ app_dict = property(_get_app_dict)
+
+ def resolve(self, path):
+ 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, e:
+ sub_tried = e.args[0].get('tried')
+ if sub_tried is not None:
+ tried.extend([(pattern.regex.pattern + ' ' + t) for t in sub_tried])
+ else:
+ tried.append(pattern.regex.pattern)
+ else:
+ if sub_match:
+ sub_match_dict = dict([(smart_str(k), v) for k, v in match.groupdict().items()])
+ sub_match_dict.update(self.default_kwargs)
+ for k, v in sub_match[2].iteritems():
+ sub_match_dict[smart_str(k)] = v
+ return sub_match[0], sub_match[1], sub_match_dict
+ tried.append(pattern.regex.pattern)
+ raise Resolver404, {'tried': tried, 'path': new_path}
+ raise Resolver404, {'path' : path}
+
+ def _get_urlconf_module(self):
+ try:
+ return self._urlconf_module
+ except AttributeError:
+ self._urlconf_module = import_module(self.urlconf_name)
+ return self._urlconf_module
+ urlconf_module = property(_get_urlconf_module)
+
+ def _get_url_patterns(self):
+ patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
+ try:
+ iter(patterns)
+ except TypeError:
+ raise ImproperlyConfigured("The included urlconf %s doesn't have any "
+ "patterns in it" % self.urlconf_name)
+ return patterns
+ url_patterns = property(_get_url_patterns)
+
+ def _resolve_special(self, view_type):
+ callback = getattr(self.urlconf_module, 'handler%s' % view_type)
+ mod_name, func_name = get_mod_func(callback)
+ try:
+ return getattr(import_module(mod_name), func_name), {}
+ except (ImportError, AttributeError), e:
+ raise ViewDoesNotExist, "Tried %s. Error was: %s" % (callback, str(e))
+
+ def resolve404(self):
+ return self._resolve_special('404')
+
+ def resolve500(self):
+ return self._resolve_special('500')
+
+ def reverse(self, lookup_view, *args, **kwargs):
+ if args and kwargs:
+ raise ValueError("Don't mix *args and **kwargs in call to reverse()!")
+ try:
+ lookup_view = get_callable(lookup_view, True)
+ except (ImportError, AttributeError), e:
+ raise NoReverseMatch("Error importing '%s': %s." % (lookup_view, e))
+ possibilities = self.reverse_dict.getlist(lookup_view)
+ for possibility, pattern in possibilities:
+ for result, params in possibility:
+ if args:
+ if len(args) != len(params):
+ continue
+ unicode_args = [force_unicode(val) for val in args]
+ candidate = result % dict(zip(params, unicode_args))
+ else:
+ if set(kwargs.keys()) != set(params):
+ continue
+ unicode_kwargs = dict([(k, force_unicode(v)) for (k, v) in kwargs.items()])
+ candidate = result % unicode_kwargs
+ if re.search(u'^%s' % pattern, candidate, re.UNICODE):
+ return candidate
+ # 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
+ raise NoReverseMatch("Reverse for '%s' with arguments '%s' and keyword "
+ "arguments '%s' not found." % (lookup_view_s, args, kwargs))
+
+def resolve(path, urlconf=None):
+ return get_resolver(urlconf).resolve(path)
+
+def reverse(viewname, urlconf=None, args=None, kwargs=None, prefix=None, current_app=None):
+ resolver = get_resolver(urlconf)
+ args = args or []
+ kwargs = kwargs or {}
+
+ if prefix is None:
+ prefix = get_script_prefix()
+
+ if not isinstance(viewname, basestring):
+ view = viewname
+ else:
+ parts = viewname.split(':')
+ parts.reverse()
+ view = parts[0]
+ path = parts[1:]
+
+ resolved_path = []
+ 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)
+ prefix = prefix + extra
+ except KeyError, 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)
+
+ return iri_to_uri(u'%s%s' % (prefix, resolver.reverse(view,
+ *args, **kwargs)))
+
+def clear_url_caches():
+ global _resolver_cache
+ global _callable_cache
+ _resolver_cache.clear()
+ _callable_cache.clear()
+
+def set_script_prefix(prefix):
+ """
+ Sets the script prefix for the current thread.
+ """
+ if not prefix.endswith('/'):
+ prefix += '/'
+ _prefixes[currentThread()] = 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 _prefixes.get(currentThread(), u'/')
+