2 from UserDict import DictMixin
3 from hashlib import sha1
5 from django.contrib.sites.models import Site
6 from django.core.cache import cache
7 from django.core.exceptions import ValidationError
8 from django.core.urlresolvers import NoReverseMatch
9 from django.core.validators import RegexValidator, MinValueValidator
10 from django.db import models
11 from django.forms.models import model_to_dict
13 from philo.models.base import TreeEntity, TreeEntityManager, Entity
14 from philo.models.nodes import Node, TargetURLModel
17 DEFAULT_NAVIGATION_DEPTH = 3
20 class NavigationMapper(object, DictMixin):
22 The :class:`NavigationMapper` is a dictionary-like object which allows easy fetching of the root items of a navigation for a node according to a key. A :class:`NavigationMapper` instance will be available on each node instance as :attr:`Node.navigation` if :mod:`~philo.contrib.shipherd` is in the :setting:`INSTALLED_APPS`
25 def __init__(self, node):
29 def __getitem__(self, key):
30 return Navigation.objects.get_for_node(self.node, key)
31 #if key not in self._cache:
33 # self._cache[key] = Navigation.objects.get_for_node(self.node, key)
34 # except Navigation.DoesNotExist:
35 # self._cache[key] = None
36 #return self._cache[key]
40 if not hasattr(self, '_navigation'):
41 self._navigation = NavigationMapper(self)
42 return self._navigation
45 Node.navigation = property(navigation)
48 class NavigationManager(models.Manager):
49 use_for_related = True
51 def get_for_node(self, node, key):
52 cache_key = self._get_cache_key(node, key)
53 cached = cache.get(cache_key)
56 opts = Node._mptt_meta
57 left = getattr(node, opts.left_attr)
58 right = getattr(node, opts.right_attr)
59 tree_id = getattr(node, opts.tree_id_attr)
61 "node__%s__lte" % opts.left_attr: left,
62 "node__%s__gte" % opts.right_attr: right,
63 "node__%s" % opts.tree_id_attr: tree_id
65 navs = self.filter(key=key, **kwargs).select_related('node').order_by('-node__%s' % opts.level_attr)
67 roots = nav.roots.all().select_related('target_node')
68 item_opts = NavigationItem._mptt_meta
72 site_root_node = Site.objects.get_current().root_node
76 tree_ids.append(getattr(root, item_opts.tree_id_attr))
77 root._cached_children = []
78 root.target_node.get_path(root=site_root_node)
81 '%s__in' % item_opts.tree_id_attr: tree_ids,
82 '%s__lt' % item_opts.level_attr: nav.depth,
83 '%s__gt' % item_opts.level_attr: 0
85 items = NavigationItem.objects.filter(**kwargs).select_related('target_node').order_by('level', 'order')
88 item._cached_children = []
89 parent_pk = getattr(item, '%s_id' % item_opts.parent_attr)
90 item.parent = by_pk[parent_pk]
91 item.parent._cached_children.append(item)
92 item.target_node.get_path(root=site_root_node)
95 cache.set(cache_key, cached)
99 def _get_cache_key(self, node, key):
100 opts = Node._mptt_meta
101 left = getattr(node, opts.left_attr)
102 right = getattr(node, opts.right_attr)
103 tree_id = getattr(node, opts.tree_id_attr)
104 parent_id = getattr(node, "%s_id" % opts.parent_attr)
106 return sha1(unicode(left) + unicode(right) + unicode(tree_id) + unicode(parent_id) + unicode(node.pk) + unicode(key)).hexdigest()
109 class Navigation(Entity):
111 :class:`Navigation` represents a group of :class:`NavigationItem`\ s that have an intrinsic relationship in terms of navigating a website. For example, a ``main`` navigation versus a ``side`` navigation, or a ``authenticated`` navigation versus an ``anonymous`` navigation.
113 A :class:`Navigation`'s :class:`NavigationItem`\ s will be accessible from its related :class:`.Node` and that :class:`.Node`'s descendants through a :class:`NavigationMapper` instance at :attr:`Node.navigation`. Example::
115 >>> node.navigation_set.all()
117 >>> parent = node.parent
118 >>> items = parent.navigation_set.get(key='main').roots.all()
119 >>> parent.navigation["main"] == node.navigation["main"] == list(items)
123 #: A :class:`NavigationManager` instance.
124 objects = NavigationManager()
126 #: The :class:`.Node` which the :class:`Navigation` is attached to. The :class:`Navigation` will also be available to all the :class:`.Node`'s descendants and will override any :class:`Navigation` with the same key on any of the :class:`.Node`'s ancestors.
127 node = models.ForeignKey(Node, related_name='navigation_set', help_text="Be available as navigation for this node.")
128 #: Each :class:`Navigation` has a ``key`` which consists of one or more word characters so that it can easily be accessed in a template as ``{{ node.navigation.this_key }}``.
129 key = models.CharField(max_length=255, validators=[RegexValidator("\w+")], help_text="Must contain one or more alphanumeric characters or underscores.", db_index=True)
130 #: There is no limit to the depth of a tree of :class:`NavigationItem`\ s, but ``depth`` will limit how much of the tree will be displayed.
131 depth = models.PositiveSmallIntegerField(default=DEFAULT_NAVIGATION_DEPTH, validators=[MinValueValidator(1)], help_text="Defines the maximum display depth of this navigation.")
133 def __unicode__(self):
134 return "%s[%s]" % (self.node, self.key)
137 unique_together = ('node', 'key')
140 class NavigationItem(TreeEntity, TargetURLModel):
141 #: A :class:`ForeignKey` to a :class:`Navigation` instance. If this is not null, then the :class:`NavigationItem` will be a root node of the :class:`Navigation` instance.
142 navigation = models.ForeignKey(Navigation, blank=True, null=True, related_name='roots', help_text="Be a root in this navigation tree.")
143 #: The text which will be displayed in the navigation. This is a :class:`CharField` instance with max length 50.
144 text = models.CharField(max_length=50)
146 #: The order in which the :class:`NavigationItem` will be displayed.
147 order = models.PositiveSmallIntegerField(default=0)
149 def get_path(self, root=None, pathsep=u' › ', field='text'):
150 return super(NavigationItem, self).get_path(root, pathsep, field)
151 path = property(get_path)
154 super(NavigationItem, self).clean()
155 if bool(self.parent) == bool(self.navigation):
156 raise ValidationError("Exactly one of `parent` and `navigation` must be defined.")
158 def is_active(self, request):
159 """Returns ``True`` if the :class:`NavigationItem` is considered active for a given request and ``False`` otherwise."""
160 if self.target_url == request.path:
161 # Handle the `default` case where the target_url and requested path
165 if self.target_node is None and self.url_or_subpath == "http%s://%s%s" % (request.is_secure() and 's' or '', request.get_host(), request.path):
166 # If there's no target_node, double-check whether it's a full-url
170 if self.target_node and not self.url_or_subpath:
171 # If there is a target node and it's targeted simply, but the target URL is not
172 # the same as the request path, check whether the target node is an ancestor
173 # of the requested node. If so, this is active unless the target node
174 # is the same as the ``host node`` for this navigation structure.
176 host_node = self.get_root().navigation.node
177 except AttributeError:
180 if self.target_node != host_node and self.target_node.is_ancestor_of(request.node):
185 def has_active_descendants(self, request):
186 """Returns ``True`` if the :class:`NavigationItem` has active descendants and ``False`` otherwise."""
187 for child in self.get_children():
188 if child.is_active(request) or child.has_active_descendants(request):