1 from inspect import getargspec
3 from os.path import basename
5 from django.contrib.contenttypes import generic
6 from django.contrib.contenttypes.models import ContentType
7 from django.contrib.sites.models import Site, RequestSite
8 from django.core.exceptions import ValidationError
9 from django.core.servers.basehttp import FileWrapper
10 from django.core.urlresolvers import resolve, clear_url_caches, reverse, NoReverseMatch
11 from django.db import models
12 from django.http import HttpResponse, HttpResponseServerError, HttpResponseRedirect, Http404
13 from django.utils.encoding import smart_str
15 from philo.exceptions import MIDDLEWARE_NOT_CONFIGURED, ViewCanNotProvideSubpath, ViewDoesNotProvideSubpaths
16 from philo.models.base import SlugTreeEntity, Entity, register_value_model
17 from philo.models.fields import JSONField
18 from philo.utils import ContentTypeSubclassLimiter
19 from philo.utils.entities import LazyPassthroughAttributeMapper
20 from philo.signals import view_about_to_render, view_finished_rendering
23 __all__ = ('Node', 'View', 'MultiView', 'Redirect', 'File')
26 _view_content_type_limiter = ContentTypeSubclassLimiter(None)
29 class Node(SlugTreeEntity):
31 :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.
34 view_content_type = models.ForeignKey(ContentType, related_name='node_view_set', limit_choices_to=_view_content_type_limiter, blank=True, null=True)
35 view_object_id = models.PositiveIntegerField(blank=True, null=True)
36 #: :class:`GenericForeignKey` to a non-abstract subclass of :class:`View`
37 view = generic.GenericForeignKey('view_content_type', 'view_object_id')
40 def accepts_subpath(self):
41 """A property shortcut for :attr:`self.view.accepts_subpath <View.accepts_subpath>`"""
42 if self.view_object_id and self.view_content_type_id:
43 return ContentType.objects.get_for_id(self.view_content_type_id).model_class().accepts_subpath
46 def handles_subpath(self, subpath):
47 if self.view_object_id and self.view_content_type_id:
48 return ContentType.objects.get_for_id(self.view_content_type_id).model_class().handles_subpath(subpath)
51 def render_to_response(self, request, extra_context=None):
52 """This is a shortcut method for :meth:`View.render_to_response`"""
53 if self.view_object_id and self.view_content_type_id:
54 view_model = ContentType.objects.get_for_id(self.view_content_type_id).model_class()
55 self.view = view_model._default_manager.select_related(depth=1).get(pk=self.view_object_id)
56 return self.view.render_to_response(request, extra_context)
59 def get_absolute_url(self, request=None, with_domain=False, secure=False):
61 This is essentially a shortcut for calling :meth:`construct_url` without a subpath.
63 :returns: The absolute url of the node on the current site.
66 return self.construct_url(request=request, with_domain=with_domain, secure=secure)
68 def construct_url(self, subpath="/", request=None, with_domain=False, secure=False):
70 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.
72 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`.
74 :meth:`construct_url` may raise the following exceptions:
76 - :class:`NoReverseMatch` if "philo-root" is not reversable -- for example, if :mod:`philo.urls` is not included anywhere in your urlpatterns.
77 - :class:`Site.DoesNotExist <ObjectDoesNotExist>` if with_domain is True but no :class:`Site` or :class:`RequestSite` can be built.
78 - :class:`~philo.exceptions.AncestorDoesNotExist` if the root node of the site isn't an ancestor of the node constructing the URL.
80 :param string subpath: The subpath to be constructed beyond beyond the node's URL.
81 :param request: :class:`HttpRequest` instance. Will be used to construct a :class:`RequestSite` if :meth:`Site.objects.get_current` fails.
82 :param with_domain: Whether the constructed URL should include a domain name and protocol.
83 :param secure: Whether the protocol, if included, should be http:// or https://.
84 :returns: A constructed url for accessing the given subpath of the current node instance.
87 # Try reversing philo-root first, since we can't do anything if that fails.
88 root_url = reverse('philo-root')
91 current_site = Site.objects.get_current()
92 except Site.DoesNotExist:
93 if request is not None:
94 current_site = RequestSite(request)
96 # If they want a domain and we can't figure one out,
97 # best to reraise the error to let them know.
102 root = getattr(current_site, 'root_node', None)
103 path = self.get_path(root=root)
105 if current_site and with_domain:
106 domain = "http%s://%s" % (secure and "s" or "", current_site.domain)
110 if not path or subpath == "/":
111 subpath = subpath[1:]
113 return '%s%s%s%s' % (domain, root_url, path, subpath)
115 class Meta(SlugTreeEntity.Meta):
119 # the following line enables the selection of a node as the root for a given django.contrib.sites Site object
120 models.ForeignKey(Node, related_name='sites', null=True, blank=True).contribute_to_class(Site, 'root_node')
125 :class:`View` is an abstract model that represents an item which can be "rendered", generally in response to an :class:`HttpRequest`.
128 #: A generic relation back to nodes.
129 nodes = generic.GenericRelation(Node, content_type_field='view_content_type', object_id_field='view_object_id')
131 #: An attribute on the class which defines whether this :class:`View` can handle subpaths. Default: ``False``
132 accepts_subpath = False
135 def handles_subpath(cls, subpath):
136 """Returns True if the :class:`View` handles the given subpath, and False otherwise."""
137 if not cls.accepts_subpath and subpath != "/":
141 def reverse(self, view_name=None, args=None, kwargs=None, node=None, obj=None):
143 If :attr:`accepts_subpath` is True, try to reverse a URL using the given parameters using ``self`` as the urlconf.
145 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.
147 :param view_name: The name of the view to be reversed.
148 :param args: Extra args for reversing the view.
149 :param kwargs: A dictionary of arguments for reversing the view.
150 :param node: The node whose subpath this is.
151 :param obj: An object to be passed to :meth:`get_reverse_params` to generate a view_name, args, and kwargs for reversal.
152 :returns: A subpath beyond the node that reverses the view, or an absolute url that reverses the view if a node was passed in.
153 :except philo.exceptions.ViewDoesNotProvideSubpaths: if :attr:`accepts_subpath` is False
154 :except philo.exceptions.ViewCanNotProvideSubpath: if a reversal is not possible.
157 if not self.accepts_subpath:
158 raise ViewDoesNotProvideSubpaths
161 # Perhaps just override instead of combining?
162 obj_view_name, obj_args, obj_kwargs = self.get_reverse_params(obj)
163 if view_name is None:
164 view_name = obj_view_name
165 args = list(obj_args) + list(args or [])
166 obj_kwargs.update(kwargs or {})
170 subpath = reverse(view_name, urlconf=self, args=args or [], kwargs=kwargs or {})
171 except NoReverseMatch, e:
172 raise ViewCanNotProvideSubpath(e.message)
175 return node.construct_url(subpath)
178 def get_reverse_params(self, obj):
180 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`.
183 raise NotImplementedError("View subclasses must implement get_reverse_params to support subpaths.")
185 def attributes_with_node(self, node, mapper=LazyPassthroughAttributeMapper):
187 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.
190 return mapper((self, node))
192 def render_to_response(self, request, extra_context=None):
194 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.
196 :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``.
199 if not hasattr(request, 'node'):
200 raise MIDDLEWARE_NOT_CONFIGURED
202 extra_context = extra_context or {}
203 view_about_to_render.send(sender=self, request=request, extra_context=extra_context)
204 response = self.actually_render_to_response(request, extra_context)
205 view_finished_rendering.send(sender=self, response=response)
208 def actually_render_to_response(self, request, extra_context=None):
209 """Concrete subclasses must override this method to provide the business logic for turning a ``request`` and ``extra_context`` into an :class:`HttpResponse`."""
210 raise NotImplementedError('View subclasses must implement actually_render_to_response.')
216 _view_content_type_limiter.cls = View
219 class MultiView(View):
221 :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:
224 #: Same as :attr:`View.accepts_subpath`. Default: ``True``
225 accepts_subpath = True
228 def urlpatterns(self):
229 """Returns urlpatterns that point to views (generally methods on the class). :class:`MultiView`\ s can be thought of as "managing" these subpaths."""
230 raise NotImplementedError("MultiView subclasses must implement urlpatterns.")
232 def actually_render_to_response(self, request, extra_context=None):
234 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.
238 subpath = request.node._subpath
239 view, args, kwargs = resolve(subpath, urlconf=self)
240 view_args = getargspec(view)
241 if extra_context is not None and ('extra_context' in view_args[0] or view_args[2] is not None):
242 if 'extra_context' in kwargs:
243 extra_context.update(kwargs['extra_context'])
244 kwargs['extra_context'] = extra_context
245 return view(request, *args, **kwargs)
247 def get_context(self):
248 """Hook for providing instance-specific context - such as the value of a Field - to any view methods on the instance."""
251 def basic_view(self, field_name):
253 Given the name of a field on the class, accesses the value of
254 that field and treats it as a ``View`` instance. Creates a
255 basic context based on self.get_context() and any extra_context
256 that was passed in, then calls the ``View`` instance's
257 render_to_response() method. This method is meant to be called
258 to return a view function appropriate for urlpatterns.
260 :param field_name: The name of a field on the instance which contains a :class:`View` subclass instance.
261 :returns: A simple view function.
265 class Foo(Multiview):
266 page = models.ForeignKey(Page)
269 def urlpatterns(self):
270 urlpatterns = patterns('',
271 url(r'^$', self.basic_view('page'))
276 field = self._meta.get_field(field_name)
277 view = getattr(self, field.name, None)
279 def inner(request, extra_context=None, **kwargs):
282 context = self.get_context()
283 context.update(extra_context or {})
284 return view.render_to_response(request, extra_context=context)
292 class TargetURLModel(models.Model):
293 """An abstract parent class for models which deal in targeting a url."""
294 #: An optional :class:`ForeignKey` to a :class:`.Node`. If provided, that node will be used as the basis for the redirect.
295 target_node = models.ForeignKey(Node, blank=True, null=True, related_name="%(app_label)s_%(class)s_related")
296 #: A :class:`CharField` which may contain an absolute or relative URL, or the name of a node's subpath.
297 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.")
298 #: 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.
299 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.")
302 if not self.target_node and not self.url_or_subpath:
303 raise ValidationError("Either a target node or a url must be defined.")
305 if self.reversing_parameters and not (self.url_or_subpath or self.target_node):
306 raise ValidationError("Reversing parameters require either a view name or a target node.")
309 self.get_target_url()
310 except (NoReverseMatch, ViewCanNotProvideSubpath), e:
311 raise ValidationError(e.message)
313 super(TargetURLModel, self).clean()
315 def get_reverse_params(self):
316 params = self.reversing_parameters
318 if isinstance(params, list):
320 elif isinstance(params, dict):
321 # Convert unicode keys to strings for Python < 2.6.5. Compare
322 # http://stackoverflow.com/questions/4598604/how-to-pass-unicode-keywords-to-kwargs
323 kwargs = dict([(smart_str(k, 'ascii'), v) for k, v in params.items()])
324 return self.url_or_subpath, args, kwargs
326 def get_target_url(self):
327 """Calculates and returns the target url based on the :attr:`target_node`, :attr:`url_or_subpath`, and :attr:`reversing_parameters`."""
328 node = self.target_node
329 if node is not None and node.accepts_subpath and self.url_or_subpath:
330 if self.reversing_parameters is not None:
331 view_name, args, kwargs = self.get_reverse_params()
332 subpath = node.view.reverse(view_name, args=args, kwargs=kwargs)
334 subpath = self.url_or_subpath
335 if subpath[0] != '/':
336 subpath = '/' + subpath
337 return node.construct_url(subpath)
338 elif node is not None:
339 return node.get_absolute_url()
341 if self.reversing_parameters is not None:
342 view_name, args, kwargs = self.get_reverse_params()
343 return reverse(view_name, args=args, kwargs=kwargs)
344 return self.url_or_subpath
345 target_url = property(get_target_url)
351 class Redirect(TargetURLModel, View):
352 """Represents a 301 or 302 redirect to a different url on an absolute or relative path."""
353 #: A choices tuple of redirect status codes (temporary or permanent).
358 #: An :class:`IntegerField` which uses :attr:`STATUS_CODES` as its choices. Determines whether the redirect is considered temporary or permanent.
359 status_code = models.IntegerField(choices=STATUS_CODES, default=302, verbose_name='redirect type')
361 def actually_render_to_response(self, request, extra_context=None):
362 """Returns an :class:`HttpResponseRedirect` to :attr:`self.target_url`."""
363 response = HttpResponseRedirect(self.target_url)
364 response.status_code = self.status_code
372 """Stores an arbitrary file."""
373 #: The name of the uploaded file. This is meant for finding the file again later, not for display.
374 name = models.CharField(max_length=255)
375 #: Defines the mimetype of the uploaded file. This will not be validated. If no mimetype is provided, it will be automatically generated based on the filename.
376 mimetype = models.CharField(max_length=255, blank=True)
377 #: Contains the uploaded file. Files are uploaded to ``philo/files/%Y/%m/%d``.
378 file = models.FileField(upload_to='philo/files/%Y/%m/%d')
381 if not self.mimetype:
382 self.mimetype = mimetypes.guess_type(self.file.name, strict=False)[0]
383 if self.mimetype is None:
384 raise ValidationError("Unknown file type.")
386 def actually_render_to_response(self, request, extra_context=None):
387 wrapper = FileWrapper(self.file)
388 response = HttpResponse(wrapper, content_type=self.mimetype)
389 response['Content-Length'] = self.file.size
390 response['Content-Disposition'] = "inline; filename=%s" % basename(self.file.name)
396 def __unicode__(self):
397 """Returns the value of :attr:`File.name`."""
401 register_value_model(Node)