--- /dev/null
+#encoding: utf-8
+from django.core.exceptions import ValidationError
+from django.core.urlresolvers import NoReverseMatch
+from django.db import models
+from django.forms.models import model_to_dict
+from philo.models import TreeEntity, JSONField, Node, TreeManager
+from philo.validators import RedirectValidator
+
+
+DEFAULT_NAVIGATION_DEPTH = 3
+
+
+class NavigationQuerySet(models.query.QuerySet):
+ """
+ This subclass is necessary to trigger cache clearing for Navigation when a mass update
+ or deletion is performed. For now, either action will trigger a clearing of the entire
+ navigation cache, since there's no convenient way to iterate over the changed or
+ deleted instances.
+ """
+ def update(self, *args, **kwargs):
+ super(NavigationQuerySet, self).update(*args, **kwargs)
+ Navigation.objects.clear_cache()
+
+ def delete(self, *args, **kwargs):
+ super(NavigationQuerySet, self).delete(*args, **kwargs)
+ Navigation.objects.clear_cache()
+
+
+class NavigationManager(TreeManager):
+
+ # Analagous to contenttypes, cache Navigation to avoid repeated lookups all over the place.
+ # Navigation will probably be used frequently.
+ _cache = {}
+
+ def get_queryset(self):
+ return NavigationQuerySet(self.model, using=self._db)
+
+ def closest_navigation(self, node):
+ """
+ Returns the set of Navigation objects for a given node's navigation. This
+ will be the most recent set of defined hosted navigation among the node's
+ ancestors. Lookups are cached so that subsequent lookups for the same node
+ don't hit the database.
+
+ TODO: Should this create the auto-generated navigation in "physical" form?
+ """
+ try:
+ return self._get_from_cache(self.db, node)
+ except KeyError:
+ # Find the most recent host!
+ ancestors = node.get_ancestors(ascending=True, include_self=True).annotate(num_navigation=models.Count("hosted_navigation"))
+
+ # Iterate down the ancestors until you find one that:
+ # a) is cached, or
+ # b) has hosted navigation.
+ nodes_to_cache = []
+ host_node = None
+ for ancestor in ancestors:
+ if self._is_cached(self.db, ancestor) or ancestor.num_navigation > 0:
+ host_node = ancestor
+ break
+ else:
+ nodes_to_cache.append(ancestor)
+
+ if not self._is_cached(self.db, host_node):
+ self._add_to_cache(self.db, host_node)
+
+ # Cache the queryset instance for every node that was passed over, as well.
+ hosted_navigation = self._get_from_cache(self.db, host_node)
+ for node in nodes_to_cache:
+ self._add_to_cache(self.db, node, hosted_navigation)
+
+ return hosted_navigation
+
+ def _add_to_cache(self, using, node, qs=None):
+ key = getattr(node, 'pk', None)
+
+ if qs is None:
+ if key is None:
+ roots = self.none()
+ else:
+ roots = node.hosted_navigation.select_related('target_node')
+
+ for root in roots:
+ root_qs = root.get_descendants(include_self=True).complex_filter({'%s__lte' % root._mptt_meta.level_attr: root.get_level() + root.depth}).exclude(depth__isnull=True)
+ if qs is None:
+ qs = root_qs
+ else:
+ qs |= root_qs
+
+ if qs is None:
+ qs = self.none()
+
+ self.__class__._cache.setdefault(using, {})[key] = qs
+
+ def _get_from_cache(self, using, node):
+ key = getattr(node, 'pk', None)
+ return self.__class__._cache[self.db][key]
+
+ def _is_cached(self, using, node):
+ try:
+ self._get_from_cache(using, node)
+ except KeyError:
+ return False
+ return True
+
+ def clear_cache(self, navigation=None):
+ """
+ Clear out the navigation cache. This needs to happen during database flushes
+ or if a navigation entry is changed to prevent caching of outdated navigation information.
+ """
+ if navigation is None:
+ self.__class__._cache.clear()
+ else:
+ cache = self.__class__._cache[self.db]
+ for pk, qs in cache.items():
+ if navigation in qs:
+ cache.pop(pk)
+
+
+class Navigation(TreeEntity):
+ objects = NavigationManager()
+ text = models.CharField(max_length=50)
+
+ hosting_node = models.ForeignKey(Node, blank=True, null=True, related_name='hosted_navigation', help_text="Be part of this node's root navigation.")
+
+ target_node = models.ForeignKey(Node, blank=True, null=True, related_name='targeting_navigation', help_text="Point to this node's url.")
+ 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.")
+ 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.")
+
+ order = models.PositiveSmallIntegerField(blank=True, null=True)
+ depth = models.PositiveSmallIntegerField(blank=True, null=True, default=DEFAULT_NAVIGATION_DEPTH, help_text="For the root of a hosted tree, defines the depth of the tree. A blank depth will hide this section of navigation. Otherwise, depth is ignored.")
+
+ def __init__(self, *args, **kwargs):
+ super(Navigation, self).__init__(*args, **kwargs)
+ self._initial_data = model_to_dict(self)
+
+ def __unicode__(self):
+ return self.get_path(field='text', pathsep=u' › ')
+
+ def clean(self):
+ # Should this be enforced? Not enforcing it would allow creation of "headers" in the navbar.
+ if not self.target_node and not self.url_or_subpath:
+ raise ValidationError("Either a target node or a url must be defined.")
+
+ if self.reversing_parameters and (not self.url_or_subpath or not self.target_node):
+ raise ValidationError("Reversing parameters require a view name and a target node.")
+
+ try:
+ self.get_target_url()
+ except NoReverseMatch, e:
+ raise ValidationError(e.message)
+
+ def get_target_url(self):
+ 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:
+ view_name = self.url_or_subpath
+ params = self.reversing_parameters
+ args = isinstance(params, list) and params or None
+ kwargs = isinstance(params, dict) and params or None
+ return node.view.reverse(view_name, args=args, kwargs=kwargs, node=node)
+ else:
+ subpath = self.url_or_subpath
+ while subpath and subpath[0] == '/':
+ subpath = subpath[1:]
+ return '%s%s' % (node.get_absolute_url(), subpath)
+ elif node is not None:
+ return node.get_absolute_url()
+ else:
+ return self.url_or_subpath
+ target_url = property(get_target_url)
+
+ def is_active(self, request):
+ # First check if this particular navigation is active. It is considered active if:
+ # - the requested node is this instance's target node and its subpath matches the requested path.
+ # - the requested node is a descendant of this instance's target node and this instance's target
+ # node is not the hosting node of this navigation structure.
+ # - this instance has no target node and the url matches either the request path or the full url.
+ # - any of this instance's children are active.
+ node = request.node
+
+ if self.target_node == node:
+ if self.target_url == request.path:
+ return True
+ elif self.target_node is None:
+ if self.url_or_subpath == request.path or self.url_or_subpath == "http%s://%s%s" % (request.is_secure() and 's' or '', request.get_host(), request.path):
+ return True
+ elif self.target_node.is_ancestor_of(node) and self.target_node != self.hosting_node:
+ return True
+
+ # Always fall back to whether the node has active children.
+ return self.has_active_children(request)
+
+ def has_active_children(self, request):
+ for child in self.get_children():
+ if child.is_active(request):
+ return True
+ return False
+
+ def _has_changed(self):
+ if model_to_dict(self) == self._initial_data:
+ return False
+ return True
+
+ def save(self, *args, **kwargs):
+ super(Navigation, self).save(*args, **kwargs)
+ if self._has_changed():
+ self._initial_data = model_to_dict(self)
+ Navigation.objects.clear_cache(self)
+
+ def delete(self, *args, **kwargs):
+ super(Navigation, self).delete(*args, **kwargs)
+ Navigation.objects.clear_cache(self)
+
+ class Meta:
+ ordering = ['order']
+ verbose_name_plural = 'navigation'
\ No newline at end of file
git.ithinksw.org / philo.git / blobdiff