--- /dev/null
+from django.db import models
+from django.contrib.contenttypes.models import ContentType
+from django.core.paginator import Paginator, EmptyPage
+from django.template import Context
+from django.template.loader_tags import ExtendsNode, ConstantIncludeNode
+
+
+def fattr(*args, **kwargs):
+ """
+ Returns a wrapper which takes a function as its only argument and sets the key/value pairs passed in with kwargs as attributes on that function. This can be used as a decorator.
+
+ Example::
+
+ >>> from philo.utils import fattr
+ >>> @fattr(short_description="Hello World!")
+ ... def x():
+ ... pass
+ ...
+ >>> x.short_description
+ 'Hello World!'
+
+ """
+ def wrapper(function):
+ for key in kwargs:
+ setattr(function, key, kwargs[key])
+ return function
+ return wrapper
+
+
+### ContentTypeLimiters
+
+
+class ContentTypeLimiter(object):
+ def q_object(self):
+ return models.Q(pk__in=[])
+
+ def add_to_query(self, query, *args, **kwargs):
+ query.add_q(self.q_object(), *args, **kwargs)
+
+
+class ContentTypeRegistryLimiter(ContentTypeLimiter):
+ """Can be used to limit the choices for a :class:`ForeignKey` or :class:`ManyToManyField` to the :class:`ContentType`\ s which have been registered with this limiter."""
+ def __init__(self):
+ self.classes = []
+
+ def register_class(self, cls):
+ """Registers a model class with this limiter."""
+ self.classes.append(cls)
+
+ def unregister_class(self, cls):
+ """Unregisters a model class from this limiter."""
+ self.classes.remove(cls)
+
+ def q_object(self):
+ contenttype_pks = []
+ for cls in self.classes:
+ try:
+ if issubclass(cls, models.Model):
+ if not cls._meta.abstract:
+ contenttype = ContentType.objects.get_for_model(cls)
+ contenttype_pks.append(contenttype.pk)
+ except:
+ pass
+ return models.Q(pk__in=contenttype_pks)
+
+
+class ContentTypeSubclassLimiter(ContentTypeLimiter):
+ """
+ Can be used to limit the choices for a :class:`ForeignKey` or :class:`ManyToManyField` to the :class:`ContentType`\ s for all non-abstract models which subclass the class passed in on instantiation.
+
+ :param cls: The class whose non-abstract subclasses will be valid choices.
+ :param inclusive: Whether ``cls`` should also be considered a valid choice (if it is a non-abstract subclass of :class:`models.Model`)
+
+ """
+ def __init__(self, cls, inclusive=False):
+ self.cls = cls
+ self.inclusive = inclusive
+
+ def q_object(self):
+ contenttype_pks = []
+ def handle_subclasses(cls):
+ for subclass in cls.__subclasses__():
+ try:
+ if issubclass(subclass, models.Model):
+ if not subclass._meta.abstract:
+ if not self.inclusive and subclass is self.cls:
+ continue
+ contenttype = ContentType.objects.get_for_model(subclass)
+ contenttype_pks.append(contenttype.pk)
+ handle_subclasses(subclass)
+ except:
+ pass
+ handle_subclasses(self.cls)
+ return models.Q(pk__in=contenttype_pks)
+
+
+### Pagination
+
+
+def paginate(objects, per_page=None, page_number=1):
+ """
+ Given a list of objects, return a (``paginator``, ``page``, ``objects``) tuple.
+
+ :param objects: The list of objects to be paginated.
+ :param per_page: The number of objects per page.
+ :param page_number: The number of the current page.
+ :returns tuple: (``paginator``, ``page``, ``objects``) where ``paginator`` is a :class:`django.core.paginator.Paginator` instance, ``page`` is the result of calling :meth:`Paginator.page` with ``page_number``, and objects is ``page.objects``. Any of the return values which can't be calculated will be returned as ``None``.
+
+ """
+ try:
+ per_page = int(per_page)
+ except (TypeError, ValueError):
+ # Then either it wasn't set or it was set to an invalid value
+ paginator = page = None
+ else:
+ # There also shouldn't be pagination if the list is too short. Try count()
+ # first - good chance it's a queryset, where count is more efficient.
+ try:
+ if objects.count() <= per_page:
+ paginator = page = None
+ except AttributeError:
+ if len(objects) <= per_page:
+ paginator = page = None
+
+ try:
+ return paginator, page, objects
+ except NameError:
+ pass
+
+ paginator = Paginator(objects, per_page)
+ try:
+ page_number = int(page_number)
+ except:
+ page_number = 1
+
+ try:
+ page = paginator.page(page_number)
+ except EmptyPage:
+ page = None
+ else:
+ objects = page.object_list
+
+ return paginator, page, objects
+
+
+### Facilitating template analysis.
+
+
+LOADED_TEMPLATE_ATTR = '_philo_loaded_template'
+BLANK_CONTEXT = Context()
+
+
+def get_extended(self):
+ return self.get_parent(BLANK_CONTEXT)
+
+
+def get_included(self):
+ return self.template
+
+
+# We ignore the IncludeNode because it will never work in a blank context.
+setattr(ExtendsNode, LOADED_TEMPLATE_ATTR, property(get_extended))
+setattr(ConstantIncludeNode, LOADED_TEMPLATE_ATTR, property(get_included))
\ No newline at end of file
git.ithinksw.org / philo.git / blobdiff