X-Git-Url: http://git.ithinksw.org/philo.git/blobdiff_plain/fb8a270fa22abc217efc471d860c76d5a2352c61..6dc154ec98d58159b3e75447ce7b7fe5642acec4:/philo/models/nodes.py diff --git a/philo/models/nodes.py b/philo/models/nodes.py index 99be196..58d1b96 100644 --- a/philo/models/nodes.py +++ b/philo/models/nodes.py @@ -1,59 +1,103 @@ -from django.db import models -from django.contrib.contenttypes.models import ContentType +from inspect import getargspec +import mimetypes +from os.path import basename + +from django.conf import settings from django.contrib.contenttypes import generic +from django.contrib.contenttypes.models import ContentType from django.contrib.sites.models import Site, RequestSite -from django.http import HttpResponse, HttpResponseServerError, HttpResponseRedirect, Http404 +from django.core.cache import cache from django.core.exceptions import ValidationError from django.core.servers.basehttp import FileWrapper from django.core.urlresolvers import resolve, clear_url_caches, reverse, NoReverseMatch -from django.template import add_to_builtins as register_templatetags +from django.db import models +from django.http import HttpResponse, HttpResponseServerError, HttpResponseRedirect, Http404 from django.utils.encoding import smart_str -from inspect import getargspec -from philo.exceptions import MIDDLEWARE_NOT_CONFIGURED -from philo.models.base import TreeEntity, Entity, QuerySetMapper, register_value_model + +from philo.exceptions import MIDDLEWARE_NOT_CONFIGURED, ViewCanNotProvideSubpath, ViewDoesNotProvideSubpaths +from philo.models.base import SlugTreeEntity, Entity, register_value_model from philo.models.fields import JSONField from philo.utils import ContentTypeSubclassLimiter -from philo.validators import RedirectValidator -from philo.exceptions import ViewCanNotProvideSubpath, ViewDoesNotProvideSubpaths, AncestorDoesNotExist +from philo.utils.entities import LazyPassthroughAttributeMapper from philo.signals import view_about_to_render, view_finished_rendering +__all__ = ('Node', 'View', 'MultiView', 'Redirect', 'File') + + _view_content_type_limiter = ContentTypeSubclassLimiter(None) +CACHE_PHILO_ROOT = getattr(settings, "PHILO_CACHE_PHILO_ROOT", True) -class Node(TreeEntity): - view_content_type = models.ForeignKey(ContentType, related_name='node_view_set', limit_choices_to=_view_content_type_limiter) - view_object_id = models.PositiveIntegerField() +class Node(SlugTreeEntity): + """ + :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. + + """ + view_content_type = models.ForeignKey(ContentType, related_name='node_view_set', limit_choices_to=_view_content_type_limiter, blank=True, null=True) + view_object_id = models.PositiveIntegerField(blank=True, null=True) + #: :class:`GenericForeignKey` to a non-abstract subclass of :class:`View` view = generic.GenericForeignKey('view_content_type', 'view_object_id') @property def accepts_subpath(self): - if self.view: - return self.view.accepts_subpath + """A property shortcut for :attr:`self.view.accepts_subpath `""" + if self.view_object_id and self.view_content_type_id: + return ContentType.objects.get_for_id(self.view_content_type_id).model_class().accepts_subpath return False def handles_subpath(self, subpath): - return self.view.handles_subpath(subpath) + if self.view_object_id and self.view_content_type_id: + return ContentType.objects.get_for_id(self.view_content_type_id).model_class().handles_subpath(subpath) + return False def render_to_response(self, request, extra_context=None): - return self.view.render_to_response(request, extra_context) + """This is a shortcut method for :meth:`View.render_to_response`""" + if self.view_object_id and self.view_content_type_id: + view_model = ContentType.objects.get_for_id(self.view_content_type_id).model_class() + self.view = view_model._default_manager.select_related(depth=1).get(pk=self.view_object_id) + return self.view.render_to_response(request, extra_context) + raise Http404 def get_absolute_url(self, request=None, with_domain=False, secure=False): + """ + This is essentially a shortcut for calling :meth:`construct_url` without a subpath. + + :returns: The absolute url of the node on the current site. + + """ return self.construct_url(request=request, with_domain=with_domain, secure=secure) def construct_url(self, subpath="/", request=None, with_domain=False, secure=False): """ - This method will construct a URL based on the Node's location. - If a request is passed in, that will be used as a backup in case - the Site lookup fails. The Site lookup takes precedence because - it's what's used to find the root node. This will raise: - - NoReverseMatch if philo-root is not reverseable - - Site.DoesNotExist if a domain is requested but not buildable. - - AncestorDoesNotExist if the root node of the site isn't an - ancestor of this instance. + 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. + + 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`. + + Because this method will be called frequently and will always try to reverse ``philo-root``, the results of that reversal will be cached by default. This can be disabled by setting :setting:`PHILO_CACHE_PHILO_ROOT` to ``False``. + + :meth:`construct_url` may raise the following exceptions: + + - :class:`NoReverseMatch` if "philo-root" is not reversable -- for example, if :mod:`philo.urls` is not included anywhere in your urlpatterns. + - :class:`Site.DoesNotExist ` if with_domain is True but no :class:`Site` or :class:`RequestSite` can be built. + - :class:`~philo.exceptions.AncestorDoesNotExist` if the root node of the site isn't an ancestor of the node constructing the URL. + + :param string subpath: The subpath to be constructed beyond beyond the node's URL. + :param request: :class:`HttpRequest` instance. Will be used to construct a :class:`RequestSite` if :meth:`Site.objects.get_current` fails. + :param with_domain: Whether the constructed URL should include a domain name and protocol. + :param secure: Whether the protocol, if included, should be http:// or https://. + :returns: A constructed url for accessing the given subpath of the current node instance. + """ # Try reversing philo-root first, since we can't do anything if that fails. - root_url = reverse('philo-root') + if CACHE_PHILO_ROOT: + key = "CACHE_PHILO_ROOT__" + settings.ROOT_URLCONF + root_url = cache.get(key) + if root_url is None: + root_url = reverse('philo-root') + cache.set(key, root_url) + else: + root_url = reverse('philo-root') try: current_site = Site.objects.get_current() @@ -80,7 +124,7 @@ class Node(TreeEntity): return '%s%s%s%s' % (domain, root_url, path, subpath) - class Meta: + class Meta(SlugTreeEntity.Meta): app_label = 'philo' @@ -89,18 +133,39 @@ models.ForeignKey(Node, related_name='sites', null=True, blank=True).contribute_ class View(Entity): + """ + :class:`View` is an abstract model that represents an item which can be "rendered", generally in response to an :class:`HttpRequest`. + + """ + #: A generic relation back to nodes. nodes = generic.GenericRelation(Node, content_type_field='view_content_type', object_id_field='view_object_id') + #: An attribute on the class which defines whether this :class:`View` can handle subpaths. Default: ``False`` accepts_subpath = False - def handles_subpath(self, subpath): - if not self.accepts_subpath and subpath != "/": + @classmethod + def handles_subpath(cls, subpath): + """Returns True if the :class:`View` handles the given subpath, and False otherwise.""" + if not cls.accepts_subpath and subpath != "/": return False return True def reverse(self, view_name=None, args=None, kwargs=None, node=None, obj=None): - """Shortcut method to handle the common pattern of getting the - absolute url for a view's subpaths.""" + """ + If :attr:`accepts_subpath` is True, try to reverse a URL using the given parameters using ``self`` as the urlconf. + + 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. + + :param view_name: The name of the view to be reversed. + :param args: Extra args for reversing the view. + :param kwargs: A dictionary of arguments for reversing the view. + :param node: The node whose subpath this is. + :param obj: An object to be passed to :meth:`get_reverse_params` to generate a view_name, args, and kwargs for reversal. + :returns: A subpath beyond the node that reverses the view, or an absolute url that reverses the view if a node was passed in. + :except philo.exceptions.ViewDoesNotProvideSubpaths: if :attr:`accepts_subpath` is False + :except philo.exceptions.ViewCanNotProvideSubpath: if a reversal is not possible. + + """ if not self.accepts_subpath: raise ViewDoesNotProvideSubpaths @@ -123,13 +188,26 @@ class View(Entity): return subpath def get_reverse_params(self, obj): - """This method should return a view_name, args, kwargs tuple suitable for reversing a url for the given obj using self as the urlconf.""" + """ + 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`. + + """ raise NotImplementedError("View subclasses must implement get_reverse_params to support subpaths.") - def attributes_with_node(self, node): - return QuerySetMapper(self.attribute_set, passthrough=node.attributes) + def attributes_with_node(self, node, mapper=LazyPassthroughAttributeMapper): + """ + 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. + + """ + return mapper((self, node)) def render_to_response(self, request, extra_context=None): + """ + 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. + + :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``. + + """ if not hasattr(request, 'node'): raise MIDDLEWARE_NOT_CONFIGURED @@ -140,6 +218,7 @@ class View(Entity): return response def actually_render_to_response(self, request, extra_context=None): + """Concrete subclasses must override this method to provide the business logic for turning a ``request`` and ``extra_context`` into an :class:`HttpResponse`.""" raise NotImplementedError('View subclasses must implement actually_render_to_response.') class Meta: @@ -150,24 +229,25 @@ _view_content_type_limiter.cls = View class MultiView(View): + """ + :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: + + """ + #: Same as :attr:`View.accepts_subpath`. Default: ``True`` accepts_subpath = True @property def urlpatterns(self): + """Returns urlpatterns that point to views (generally methods on the class). :class:`MultiView`\ s can be thought of as "managing" these subpaths.""" raise NotImplementedError("MultiView subclasses must implement urlpatterns.") - def handles_subpath(self, subpath): - if not super(MultiView, self).handles_subpath(subpath): - return False - try: - resolve(subpath, urlconf=self) - except Http404: - return False - return True - def actually_render_to_response(self, request, extra_context=None): + """ + Resolves the remaining subpath left after finding this :class:`View`'s node using :attr:`self.urlpatterns ` and renders the view function (or method) found with the appropriate args and kwargs. + + """ clear_url_caches() - subpath = request.node.subpath + subpath = request.node._subpath view, args, kwargs = resolve(subpath, urlconf=self) view_args = getargspec(view) if extra_context is not None and ('extra_context' in view_args[0] or view_args[2] is not None): @@ -177,17 +257,33 @@ class MultiView(View): return view(request, *args, **kwargs) def get_context(self): - """Hook for providing instance-specific context - such as the value of a Field - to all views.""" + """Hook for providing instance-specific context - such as the value of a Field - to any view methods on the instance.""" return {} def basic_view(self, field_name): """ - Given the name of a field on ``self``, accesses the value of + Given the name of a field on the class, accesses the value of that field and treats it as a ``View`` instance. Creates a basic context based on self.get_context() and any extra_context that was passed in, then calls the ``View`` instance's render_to_response() method. This method is meant to be called to return a view function appropriate for urlpatterns. + + :param field_name: The name of a field on the instance which contains a :class:`View` subclass instance. + :returns: A simple view function. + + Example:: + + class Foo(Multiview): + page = models.ForeignKey(Page) + + @property + def urlpatterns(self): + urlpatterns = patterns('', + url(r'^$', self.basic_view('page')) + ) + return urlpatterns + """ field = self._meta.get_field(field_name) view = getattr(self, field.name, None) @@ -206,8 +302,12 @@ class MultiView(View): class TargetURLModel(models.Model): + """An abstract parent class for models which deal in targeting a url.""" + #: An optional :class:`ForeignKey` to a :class:`.Node`. If provided, that node will be used as the basis for the redirect. target_node = models.ForeignKey(Node, blank=True, null=True, related_name="%(app_label)s_%(class)s_related") - url_or_subpath = models.CharField(max_length=200, validators=[RedirectValidator()], blank=True, help_text="Point to this url or, if a node is defined and accepts subpaths, this subpath of the node.") + #: A :class:`CharField` which may contain an absolute or relative URL, or the name of a node's subpath. + 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.") + #: 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. 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.") def clean(self): @@ -235,7 +335,17 @@ class TargetURLModel(models.Model): kwargs = dict([(smart_str(k, 'ascii'), v) for k, v in params.items()]) return self.url_or_subpath, args, kwargs - def get_target_url(self): + def get_target_url(self, memoize=True): + """Calculates and returns the target url based on the :attr:`target_node`, :attr:`url_or_subpath`, and :attr:`reversing_parameters`. The results will be memoized by default; this can be prevented by passing in ``memoize=False``.""" + if memoize: + memo_args = (self.target_node_id, self.url_or_subpath, self.reversing_parameters_json) + try: + return self._target_url_memo[memo_args] + except AttributeError: + self._target_url_memo = {} + except KeyError: + pass + node = self.target_node if node is not None and node.accepts_subpath and self.url_or_subpath: if self.reversing_parameters is not None: @@ -245,14 +355,19 @@ class TargetURLModel(models.Model): subpath = self.url_or_subpath if subpath[0] != '/': subpath = '/' + subpath - return node.construct_url(subpath) + target_url = node.construct_url(subpath) elif node is not None: - return node.get_absolute_url() + target_url = node.get_absolute_url() else: if self.reversing_parameters is not None: view_name, args, kwargs = self.get_reverse_params() - return reverse(view_name, args=args, kwargs=kwargs) - return self.url_or_subpath + target_url = reverse(view_name, args=args, kwargs=kwargs) + else: + target_url = self.url_or_subpath + + if memoize: + self._target_url_memo[memo_args] = target_url + return target_url target_url = property(get_target_url) class Meta: @@ -260,13 +375,17 @@ class TargetURLModel(models.Model): class Redirect(TargetURLModel, View): + """Represents a 301 or 302 redirect to a different url on an absolute or relative path.""" + #: A choices tuple of redirect status codes (temporary or permanent). STATUS_CODES = ( (302, 'Temporary'), (301, 'Permanent'), ) + #: An :class:`IntegerField` which uses :attr:`STATUS_CODES` as its choices. Determines whether the redirect is considered temporary or permanent. status_code = models.IntegerField(choices=STATUS_CODES, default=302, verbose_name='redirect type') def actually_render_to_response(self, request, extra_context=None): + """Returns an :class:`HttpResponseRedirect` to :attr:`self.target_url`.""" response = HttpResponseRedirect(self.target_url) response.status_code = self.status_code return response @@ -276,23 +395,33 @@ class Redirect(TargetURLModel, View): class File(View): - """ For storing arbitrary files """ - - mimetype = models.CharField(max_length=255) + """Stores an arbitrary file.""" + #: The name of the uploaded file. This is meant for finding the file again later, not for display. + name = models.CharField(max_length=255) + #: 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. + mimetype = models.CharField(max_length=255, blank=True) + #: Contains the uploaded file. Files are uploaded to ``philo/files/%Y/%m/%d``. file = models.FileField(upload_to='philo/files/%Y/%m/%d') + def clean(self): + if not self.mimetype: + self.mimetype = mimetypes.guess_type(self.file.name, strict=False)[0] + if self.mimetype is None: + raise ValidationError("Unknown file type.") + def actually_render_to_response(self, request, extra_context=None): wrapper = FileWrapper(self.file) response = HttpResponse(wrapper, content_type=self.mimetype) response['Content-Length'] = self.file.size + response['Content-Disposition'] = "inline; filename=%s" % basename(self.file.name) return response class Meta: app_label = 'philo' def __unicode__(self): - return self.file.name + """Returns the value of :attr:`File.name`.""" + return self.name -register_templatetags('philo.templatetags.nodes') register_value_model(Node) \ No newline at end of file