1 from inspect import getargspec
3 from django.contrib.contenttypes import generic
4 from django.contrib.contenttypes.models import ContentType
5 from django.contrib.sites.models import Site, RequestSite
6 from django.core.exceptions import ValidationError
7 from django.core.servers.basehttp import FileWrapper
8 from django.core.urlresolvers import resolve, clear_url_caches, reverse, NoReverseMatch
9 from django.db import models
10 from django.http import HttpResponse, HttpResponseServerError, HttpResponseRedirect, Http404
11 from django.utils.encoding import smart_str
13 from philo.exceptions import MIDDLEWARE_NOT_CONFIGURED, ViewCanNotProvideSubpath, ViewDoesNotProvideSubpaths
14 from philo.models.base import SlugTreeEntity, Entity, register_value_model
15 from philo.models.fields import JSONField
16 from philo.utils import ContentTypeSubclassLimiter
17 from philo.utils.entities import LazyPassthroughAttributeMapper
18 from philo.signals import view_about_to_render, view_finished_rendering
21 __all__ = ('Node', 'View', 'MultiView', 'Redirect', 'File')
24 _view_content_type_limiter = ContentTypeSubclassLimiter(None)
27 class Node(SlugTreeEntity):
29 :class:`Node`\ s are the basic building blocks of a website using Philo. They define the URL hierarchy and connect each URL to a :class:`View` subclass instance which is used to generate an HttpResponse.
32 view_content_type = models.ForeignKey(ContentType, related_name='node_view_set', limit_choices_to=_view_content_type_limiter, blank=True, null=True)
33 view_object_id = models.PositiveIntegerField(blank=True, null=True)
34 #: :class:`GenericForeignKey` to a non-abstract subclass of :class:`View`
35 view = generic.GenericForeignKey('view_content_type', 'view_object_id')
38 def accepts_subpath(self):
39 """A property shortcut for :attr:`self.view.accepts_subpath <View.accepts_subpath>`"""
41 return self.view.accepts_subpath
44 def handles_subpath(self, subpath):
46 return self.view.handles_subpath(subpath)
49 def render_to_response(self, request, extra_context=None):
50 """This is a shortcut method for :meth:`View.render_to_response`"""
52 return self.view.render_to_response(request, extra_context)
55 def get_absolute_url(self, request=None, with_domain=False, secure=False):
57 This is essentially a shortcut for calling :meth:`construct_url` without a subpath.
59 :returns: The absolute url of the node on the current site.
62 return self.construct_url(request=request, with_domain=with_domain, secure=secure)
64 def construct_url(self, subpath="/", request=None, with_domain=False, secure=False):
66 This method will do its best to construct a URL based on the Node's location. If with_domain is True, that URL will include a domain and a protocol; if secure is True as well, the protocol will be https. The request will be used to construct a domain in cases where a call to :meth:`Site.objects.get_current` fails.
68 Node urls will not contain a trailing slash unless a subpath is provided which ends with a trailing slash. Subpaths are expected to begin with a slash, as if returned by :func:`django.core.urlresolvers.reverse`.
70 :meth:`construct_url` may raise the following exceptions:
72 - :class:`NoReverseMatch` if "philo-root" is not reversable -- for example, if :mod:`philo.urls` is not included anywhere in your urlpatterns.
73 - :class:`Site.DoesNotExist <ObjectDoesNotExist>` if with_domain is True but no :class:`Site` or :class:`RequestSite` can be built.
74 - :class:`~philo.exceptions.AncestorDoesNotExist` if the root node of the site isn't an ancestor of the node constructing the URL.
76 :param string subpath: The subpath to be constructed beyond beyond the node's URL.
77 :param request: :class:`HttpRequest` instance. Will be used to construct a :class:`RequestSite` if :meth:`Site.objects.get_current` fails.
78 :param with_domain: Whether the constructed URL should include a domain name and protocol.
79 :param secure: Whether the protocol, if included, should be http:// or https://.
80 :returns: A constructed url for accessing the given subpath of the current node instance.
83 # Try reversing philo-root first, since we can't do anything if that fails.
84 root_url = reverse('philo-root')
87 current_site = Site.objects.get_current()
88 except Site.DoesNotExist:
89 if request is not None:
90 current_site = RequestSite(request)
92 # If they want a domain and we can't figure one out,
93 # best to reraise the error to let them know.
98 root = getattr(current_site, 'root_node', None)
99 path = self.get_path(root=root)
101 if current_site and with_domain:
102 domain = "http%s://%s" % (secure and "s" or "", current_site.domain)
106 if not path or subpath == "/":
107 subpath = subpath[1:]
109 return '%s%s%s%s' % (domain, root_url, path, subpath)
111 class Meta(SlugTreeEntity.Meta):
115 # the following line enables the selection of a node as the root for a given django.contrib.sites Site object
116 models.ForeignKey(Node, related_name='sites', null=True, blank=True).contribute_to_class(Site, 'root_node')
121 :class:`View` is an abstract model that represents an item which can be "rendered", generally in response to an :class:`HttpRequest`.
124 #: A generic relation back to nodes.
125 nodes = generic.GenericRelation(Node, content_type_field='view_content_type', object_id_field='view_object_id')
127 #: Property or attribute which defines whether this :class:`View` can handle subpaths. Default: ``False``
128 accepts_subpath = False
130 def handles_subpath(self, subpath):
131 """Returns True if the :class:`View` handles the given subpath, and False otherwise."""
132 if not self.accepts_subpath and subpath != "/":
136 def reverse(self, view_name=None, args=None, kwargs=None, node=None, obj=None):
138 If :attr:`accepts_subpath` is True, try to reverse a URL using the given parameters using ``self`` as the urlconf.
140 If ``obj`` is provided, :meth:`get_reverse_params` will be called and the results will be combined with any ``view_name``, ``args``, and ``kwargs`` that may have been passed in.
142 :param view_name: The name of the view to be reversed.
143 :param args: Extra args for reversing the view.
144 :param kwargs: A dictionary of arguments for reversing the view.
145 :param node: The node whose subpath this is.
146 :param obj: An object to be passed to :meth:`get_reverse_params` to generate a view_name, args, and kwargs for reversal.
147 :returns: A subpath beyond the node that reverses the view, or an absolute url that reverses the view if a node was passed in.
148 :except philo.exceptions.ViewDoesNotProvideSubpaths: if :attr:`accepts_subpath` is False
149 :except philo.exceptions.ViewCanNotProvideSubpath: if a reversal is not possible.
152 if not self.accepts_subpath:
153 raise ViewDoesNotProvideSubpaths
156 # Perhaps just override instead of combining?
157 obj_view_name, obj_args, obj_kwargs = self.get_reverse_params(obj)
158 if view_name is None:
159 view_name = obj_view_name
160 args = list(obj_args) + list(args or [])
161 obj_kwargs.update(kwargs or {})
165 subpath = reverse(view_name, urlconf=self, args=args or [], kwargs=kwargs or {})
166 except NoReverseMatch, e:
167 raise ViewCanNotProvideSubpath(e.message)
170 return node.construct_url(subpath)
173 def get_reverse_params(self, obj):
175 This method is not implemented on the base class. It should return a (``view_name``, ``args``, ``kwargs``) tuple suitable for reversing a url for the given ``obj`` using ``self`` as the urlconf. If a reversal will not be possible, this method should raise :class:`~philo.exceptions.ViewCanNotProvideSubpath`.
178 raise NotImplementedError("View subclasses must implement get_reverse_params to support subpaths.")
180 def attributes_with_node(self, node, mapper=LazyPassthroughAttributeMapper):
182 Returns a :class:`LazyPassthroughAttributeMapper` which can be used to directly retrieve the values of :class:`Attribute`\ s related to the :class:`View`, falling back on the :class:`Attribute`\ s of the passed-in :class:`Node` and its ancestors.
185 return mapper((self, node))
187 def render_to_response(self, request, extra_context=None):
189 Renders the :class:`View` as an :class:`HttpResponse`. This will raise :const:`~philo.exceptions.MIDDLEWARE_NOT_CONFIGURED` if the `request` doesn't have an attached :class:`Node`. This can happen if the :class:`~philo.middleware.RequestNodeMiddleware` is not in :setting:`settings.MIDDLEWARE_CLASSES` or if it is not functioning correctly.
191 :meth:`render_to_response` will send the :data:`~philo.signals.view_about_to_render` signal, then call :meth:`actually_render_to_response`, and finally send the :data:`~philo.signals.view_finished_rendering` signal before returning the ``response``.
194 if not hasattr(request, 'node'):
195 raise MIDDLEWARE_NOT_CONFIGURED
197 extra_context = extra_context or {}
198 view_about_to_render.send(sender=self, request=request, extra_context=extra_context)
199 response = self.actually_render_to_response(request, extra_context)
200 view_finished_rendering.send(sender=self, response=response)
203 def actually_render_to_response(self, request, extra_context=None):
204 """Concrete subclasses must override this method to provide the business logic for turning a ``request`` and ``extra_context`` into an :class:`HttpResponse`."""
205 raise NotImplementedError('View subclasses must implement actually_render_to_response.')
211 _view_content_type_limiter.cls = View
214 class MultiView(View):
216 :class:`MultiView` is an abstract model which represents a section of related pages - for example, a :class:`~philo.contrib.penfield.BlogView` might have a foreign key to :class:`Page`\ s for an index, an entry detail, an entry archive by day, and so on. :class:`!MultiView` subclasses :class:`View`, and defines the following additional methods and attributes:
219 #: Same as :attr:`View.accepts_subpath`. Default: ``True``
220 accepts_subpath = True
223 def urlpatterns(self):
224 """Returns urlpatterns that point to views (generally methods on the class). :class:`MultiView`\ s can be thought of as "managing" these subpaths."""
225 raise NotImplementedError("MultiView subclasses must implement urlpatterns.")
227 def handles_subpath(self, subpath):
228 if not super(MultiView, self).handles_subpath(subpath):
231 resolve(subpath, urlconf=self)
236 def actually_render_to_response(self, request, extra_context=None):
238 Resolves the remaining subpath left after finding this :class:`View`'s node using :attr:`self.urlpatterns <urlpatterns>` and renders the view function (or method) found with the appropriate args and kwargs.
242 subpath = request.node._subpath
243 view, args, kwargs = resolve(subpath, urlconf=self)
244 view_args = getargspec(view)
245 if extra_context is not None and ('extra_context' in view_args[0] or view_args[2] is not None):
246 if 'extra_context' in kwargs:
247 extra_context.update(kwargs['extra_context'])
248 kwargs['extra_context'] = extra_context
249 return view(request, *args, **kwargs)
251 def get_context(self):
252 """Hook for providing instance-specific context - such as the value of a Field - to any view methods on the instance."""
255 def basic_view(self, field_name):
257 Given the name of a field on the class, accesses the value of
258 that field and treats it as a ``View`` instance. Creates a
259 basic context based on self.get_context() and any extra_context
260 that was passed in, then calls the ``View`` instance's
261 render_to_response() method. This method is meant to be called
262 to return a view function appropriate for urlpatterns.
264 :param field_name: The name of a field on the instance which contains a :class:`View` subclass instance.
265 :returns: A simple view function.
269 class Foo(Multiview):
270 page = models.ForeignKey(Page)
273 def urlpatterns(self):
274 urlpatterns = patterns('',
275 url(r'^$', self.basic_view('page'))
280 field = self._meta.get_field(field_name)
281 view = getattr(self, field.name, None)
283 def inner(request, extra_context=None, **kwargs):
286 context = self.get_context()
287 context.update(extra_context or {})
288 return view.render_to_response(request, extra_context=context)
296 class TargetURLModel(models.Model):
297 """An abstract parent class for models which deal in targeting a url."""
298 #: An optional :class:`ForeignKey` to a :class:`.Node`. If provided, that node will be used as the basis for the redirect.
299 target_node = models.ForeignKey(Node, blank=True, null=True, related_name="%(app_label)s_%(class)s_related")
300 #: A :class:`CharField` which may contain an absolute or relative URL, or the name of a node's subpath.
301 url_or_subpath = models.CharField(max_length=200, blank=True, help_text="Point to this url or, if a node is defined and accepts subpaths, this subpath of the node.")
302 #: A :class:`~philo.models.fields.JSONField` instance. If the value of :attr:`reversing_parameters` is not None, the :attr:`url_or_subpath` will be treated as the name of a view to be reversed. The value of :attr:`reversing_parameters` will be passed into the reversal as args if it is a list or as kwargs if it is a dictionary. Otherwise it will be ignored.
303 reversing_parameters = JSONField(blank=True, help_text="If reversing parameters are defined, url_or_subpath will instead be interpreted as the view name to be reversed.")
306 if not self.target_node and not self.url_or_subpath:
307 raise ValidationError("Either a target node or a url must be defined.")
309 if self.reversing_parameters and not (self.url_or_subpath or self.target_node):
310 raise ValidationError("Reversing parameters require either a view name or a target node.")
313 self.get_target_url()
314 except (NoReverseMatch, ViewCanNotProvideSubpath), e:
315 raise ValidationError(e.message)
317 super(TargetURLModel, self).clean()
319 def get_reverse_params(self):
320 params = self.reversing_parameters
322 if isinstance(params, list):
324 elif isinstance(params, dict):
325 # Convert unicode keys to strings for Python < 2.6.5. Compare
326 # http://stackoverflow.com/questions/4598604/how-to-pass-unicode-keywords-to-kwargs
327 kwargs = dict([(smart_str(k, 'ascii'), v) for k, v in params.items()])
328 return self.url_or_subpath, args, kwargs
330 def get_target_url(self):
331 """Calculates and returns the target url based on the :attr:`target_node`, :attr:`url_or_subpath`, and :attr:`reversing_parameters`."""
332 node = self.target_node
333 if node is not None and node.accepts_subpath and self.url_or_subpath:
334 if self.reversing_parameters is not None:
335 view_name, args, kwargs = self.get_reverse_params()
336 subpath = node.view.reverse(view_name, args=args, kwargs=kwargs)
338 subpath = self.url_or_subpath
339 if subpath[0] != '/':
340 subpath = '/' + subpath
341 return node.construct_url(subpath)
342 elif node is not None:
343 return node.get_absolute_url()
345 if self.reversing_parameters is not None:
346 view_name, args, kwargs = self.get_reverse_params()
347 return reverse(view_name, args=args, kwargs=kwargs)
348 return self.url_or_subpath
349 target_url = property(get_target_url)
355 class Redirect(TargetURLModel, View):
356 """Represents a 301 or 302 redirect to a different url on an absolute or relative path."""
357 #: A choices tuple of redirect status codes (temporary or permanent).
362 #: An :class:`IntegerField` which uses :attr:`STATUS_CODES` as its choices. Determines whether the redirect is considered temporary or permanent.
363 status_code = models.IntegerField(choices=STATUS_CODES, default=302, verbose_name='redirect type')
365 def actually_render_to_response(self, request, extra_context=None):
366 """Returns an :class:`HttpResponseRedirect` to :attr:`self.target_url`."""
367 response = HttpResponseRedirect(self.target_url)
368 response.status_code = self.status_code
376 """Stores an arbitrary file."""
377 #: Defines the mimetype of the uploaded file. This will not be validated.
378 mimetype = models.CharField(max_length=255)
379 #: Contains the uploaded file. Files are uploaded to ``philo/files/%Y/%m/%d``.
380 file = models.FileField(upload_to='philo/files/%Y/%m/%d')
382 def actually_render_to_response(self, request, extra_context=None):
383 wrapper = FileWrapper(self.file)
384 response = HttpResponse(wrapper, content_type=self.mimetype)
385 response['Content-Length'] = self.file.size
391 def __unicode__(self):
392 """Returns the path of the uploaded file."""
393 return self.file.name
396 register_value_model(Node)