models/nodes.py

   1 from django.db import models
   2 from django.contrib.contenttypes.models import ContentType
   3 from django.contrib.contenttypes import generic
   4 from django.contrib.sites.models import Site
   5 from django.http import HttpResponse, HttpResponseServerError, HttpResponseRedirect
   6 from django.core.exceptions import ViewDoesNotExist
   7 from django.core.servers.basehttp import FileWrapper
   8 from django.core.urlresolvers import resolve, clear_url_caches, reverse, NoReverseMatch
   9 from django.template import add_to_builtins as register_templatetags
  10 from inspect import getargspec
  11 from philo.exceptions import MIDDLEWARE_NOT_CONFIGURED
  12 from philo.models.base import TreeEntity, Entity, QuerySetMapper, register_value_model
  13 from philo.models.fields import JSONField
  14 from philo.utils import ContentTypeSubclassLimiter
  15 from philo.validators import RedirectValidator
  16 from philo.exceptions import ViewCanNotProvideSubpath, ViewDoesNotProvideSubpaths, AncestorDoesNotExist
  17 from philo.signals import view_about_to_render, view_finished_rendering
  18
  19
  20 _view_content_type_limiter = ContentTypeSubclassLimiter(None)
  21 DEFAULT_NAVIGATION_DEPTH = 3
  22
  23
  24 class Node(TreeEntity):
  25         view_content_type = models.ForeignKey(ContentType, related_name='node_view_set', limit_choices_to=_view_content_type_limiter)
  26         view_object_id = models.PositiveIntegerField()
  27         view = generic.GenericForeignKey('view_content_type', 'view_object_id')
  28
  29         @property
  30         def accepts_subpath(self):
  31                 if self.view:
  32                         return self.view.accepts_subpath
  33                 return False
  34
  35         def render_to_response(self, request, extra_context=None):
  36                 return self.view.render_to_response(request, extra_context)
  37
  38         def get_absolute_url(self):
  39                 try:
  40                         root = Site.objects.get_current().root_node
  41                 except Site.DoesNotExist:
  42                         root = None
  43
  44                 try:
  45                         path = self.get_path(root=root)
  46                         if path:
  47                                 path += '/'
  48                         root_url = reverse('philo-root')
  49                         return '%s%s' % (root_url, path)
  50                 except AncestorDoesNotExist, ViewDoesNotExist:
  51                         return None
  52
  53         def get_navigation(self, depth=DEFAULT_NAVIGATION_DEPTH, current_depth=0, found_node_pks=None):
  54                 navigation = self.view.get_navigation(self, depth, current_depth)
  55
  56                 if depth == current_depth:
  57                         return navigation
  58                 import pdb
  59                 pdb.set_trace()
  60                 found_node_pks = found_node_pks or [self.pk]
  61                 ordered_child_pks = NodeNavigationOverride.objects.filter(parent=self, child__parent=self).values_list('child__pk', flat=True)
  62
  63                 children = self.children.exclude(pk__in=found_node_pks)
  64                 ordered_children = children.filter(pk__in=ordered_child_pks)
  65                 unordered_children = children.exclude(pk__in=ordered_child_pks)
  66
  67                 children = list(ordered_children) + list(unordered_children)
  68
  69                 if children:
  70                         child_navigation = []
  71                         for child in children:
  72                                 found_node_pks.append(child.pk)
  73                                 try:
  74                                         child_navigation.append(child.get_navigation(depth, current_depth + 1, found_node_pks))
  75                                 except NotImplementedError:
  76                                         pass
  77
  78                         if child_navigation:
  79                                 if 'children' in navigation:
  80                                         navigation['children'] += child_navigation
  81                                 else:
  82                                         navigation['children'] = child_navigation
  83
  84                 return navigation
  85
  86         def save(self):
  87                 super(Node, self).save()
  88
  89
  90         class Meta:
  91                 app_label = 'philo'
  92
  93
  94 # the following line enables the selection of a node as the root for a given django.contrib.sites Site object
  95 models.ForeignKey(Node, related_name='sites', null=True, blank=True).contribute_to_class(Site, 'root_node')
  96
  97
  98 class NodeNavigationOverride(Entity):
  99         parent = models.ForeignKey(Node, related_name="navigation_override_child_set")
 100         child = models.OneToOneField(Node, related_name="navigation_override")
 101         url = models.CharField(max_length=200, validators=[RedirectValidator()], blank=True)
 102         title = models.CharField(max_length=100, blank=True)
 103         order = models.PositiveSmallIntegerField(blank=True, null=True)
 104         child_navigation = JSONField()
 105
 106         def get_navigation(self, node, depth, current_depth):
 107                 if self.child_navigation:
 108                         depth = current_depth
 109                 default = node.get_navigation(depth, current_depth)
 110                 if self.url:
 111                         default['url'] = self.url
 112                 if self.title:
 113                         default['title'] = self.title
 114                 if self.child_navigation:
 115                         if 'children' in default:
 116                                 default['children'] += self.child_navigation
 117                         else:
 118                                 default['children'] = self.child_navigation
 119
 120         class Meta:
 121                 ordering = ['order']
 122
 123
 124 class View(Entity):
 125         nodes = generic.GenericRelation(Node, content_type_field='view_content_type', object_id_field='view_object_id')
 126
 127         accepts_subpath = False
 128
 129         def get_subpath(self, obj):
 130                 if not self.accepts_subpath:
 131                         raise ViewDoesNotProvideSubpaths
 132
 133                 view_name, args, kwargs = self.get_reverse_params(obj)
 134                 try:
 135                         return reverse(view_name, args=args, kwargs=kwargs, urlconf=self)
 136                 except NoReverseMatch:
 137                         raise ViewCanNotProvideSubpath
 138
 139         def get_reverse_params(self, obj):
 140                 """This method should return a view_name, args, kwargs tuple suitable for reversing a url for the given obj using self as the urlconf."""
 141                 raise NotImplementedError("View subclasses must implement get_reverse_params to support subpaths.")
 142
 143         def attributes_with_node(self, node):
 144                 return QuerySetMapper(self.attribute_set, passthrough=node.attributes)
 145
 146         def render_to_response(self, request, extra_context=None):
 147                 if not hasattr(request, 'node'):
 148                         raise MIDDLEWARE_NOT_CONFIGURED
 149
 150                 extra_context = extra_context or {}
 151                 view_about_to_render.send(sender=self, request=request, extra_context=extra_context)
 152                 response = self.actually_render_to_response(request, extra_context)
 153                 view_finished_rendering.send(sender=self, response=response)
 154                 return response
 155
 156         def actually_render_to_response(self, request, extra_context=None):
 157                 raise NotImplementedError('View subclasses must implement render_to_response.')
 158
 159         def get_navigation(self, node, depth, current_depth):
 160                 raise NotImplementedError('View subclasses must implement get_navigation.')
 161
 162         class Meta:
 163                 abstract = True
 164
 165
 166 _view_content_type_limiter.cls = View
 167
 168
 169 class MultiView(View):
 170         accepts_subpath = True
 171
 172         @property
 173         def urlpatterns(self, obj):
 174                 raise NotImplementedError("MultiView subclasses must implement urlpatterns.")
 175
 176         def actually_render_to_response(self, request, extra_context=None):
 177                 clear_url_caches()
 178                 subpath = request.node.subpath
 179                 if not subpath:
 180                         subpath = ""
 181                 subpath = "/" + subpath
 182                 view, args, kwargs = resolve(subpath, urlconf=self)
 183                 view_args = getargspec(view)
 184                 if extra_context is not None and ('extra_context' in view_args[0] or view_args[2] is not None):
 185                         if 'extra_context' in kwargs:
 186                                 extra_context.update(kwargs['extra_context'])
 187                         kwargs['extra_context'] = extra_context
 188                 return view(request, *args, **kwargs)
 189
 190         class Meta:
 191                 abstract = True
 192
 193
 194 class Redirect(View):
 195         STATUS_CODES = (
 196                 (302, 'Temporary'),
 197                 (301, 'Permanent'),
 198         )
 199         target = models.CharField(max_length=200, validators=[RedirectValidator()])
 200         status_code = models.IntegerField(choices=STATUS_CODES, default=302, verbose_name='redirect type')
 201
 202         def actually_render_to_response(self, request, extra_context=None):
 203                 response = HttpResponseRedirect(self.target)
 204                 response.status_code = self.status_code
 205                 return response
 206
 207         class Meta:
 208                 app_label = 'philo'
 209
 210
 211 # Why does this exist?
 212 class File(View):
 213         """ For storing arbitrary files """
 214
 215         mimetype = models.CharField(max_length=255)
 216         file = models.FileField(upload_to='philo/files/%Y/%m/%d')
 217
 218         def actually_render_to_response(self, request, extra_context=None):
 219                 wrapper = FileWrapper(self.file)
 220                 response = HttpResponse(wrapper, content_type=self.mimetype)
 221                 response['Content-Length'] = self.file.size
 222                 return response
 223
 224         class Meta:
 225                 app_label = 'philo'
 226
 227         def __unicode__(self):
 228                 return self.file.name
 229
 230
 231 register_templatetags('philo.templatetags.nodes')
 232 register_value_model(Node)