models.py

   1 # encoding: utf-8
   2 from django.utils.translation import ugettext_lazy as _
   3 from django.contrib.auth.models import User, Group
   4 from django.contrib.contenttypes import generic
   5 from django.contrib.contenttypes.models import ContentType
   6 from django.db import models
   7 from django.contrib.sites.models import Site
   8 from utils import fattr
   9 from django.template import add_to_builtins as register_templatetags
  10 from django.template import Template as DjangoTemplate
  11 from django.template import TemplateDoesNotExist
  12 from django.template import Context, RequestContext
  13 from django.core.exceptions import ObjectDoesNotExist
  14 try:
  15         import json
  16 except ImportError:
  17         import simplejson as json
  18 from UserDict import DictMixin
  19 from templatetags.containers import ContainerNode
  20 from django.template.loader_tags import ExtendsNode, ConstantIncludeNode, IncludeNode
  21 from django.template.loader import get_template
  22 from django.http import Http404, HttpResponse, HttpResponseServerError, HttpResponseRedirect
  23 from django.core.servers.basehttp import FileWrapper
  24 from django.conf import settings
  25
  26
  27 def register_value_model(model):
  28         pass
  29
  30
  31 def unregister_value_model(model):
  32         pass
  33
  34
  35 class Attribute(models.Model):
  36         entity_content_type = models.ForeignKey(ContentType, verbose_name='Entity type')
  37         entity_object_id = models.PositiveIntegerField(verbose_name='Entity ID')
  38         entity = generic.GenericForeignKey('entity_content_type', 'entity_object_id')
  39         key = models.CharField(max_length=255)
  40         json_value = models.TextField(verbose_name='Value (JSON)', help_text='This value must be valid JSON.')
  41
  42         def get_value(self):
  43                 return json.loads(self.json_value)
  44
  45         def set_value(self, value):
  46                 self.json_value = json.dumps(value)
  47
  48         def delete_value(self):
  49                 self.json_value = json.dumps(None)
  50
  51         value = property(get_value, set_value, delete_value)
  52
  53         def __unicode__(self):
  54                 return u'"%s": %s' % (self.key, self.value)
  55
  56
  57 class Relationship(models.Model):
  58         entity_content_type = models.ForeignKey(ContentType, related_name='relationship_entity_set', verbose_name='Entity type')
  59         entity_object_id = models.PositiveIntegerField(verbose_name='Entity ID')
  60         entity = generic.GenericForeignKey('entity_content_type', 'entity_object_id')
  61         key = models.CharField(max_length=255)
  62         value_content_type = models.ForeignKey(ContentType, related_name='relationship_value_set', verbose_name='Value type')
  63         value_object_id = models.PositiveIntegerField(verbose_name='Value ID')
  64         value = generic.GenericForeignKey('value_content_type', 'value_object_id')
  65
  66         def __unicode__(self):
  67                 return u'"%s": %s' % (self.key, self.value)
  68
  69
  70 class QuerySetMapper(object, DictMixin):
  71         def __init__(self, queryset, passthrough=None):
  72                 self.queryset = queryset
  73                 self.passthrough = passthrough
  74         def __getitem__(self, key):
  75                 try:
  76                         return self.queryset.get(key__exact=key).value
  77                 except ObjectDoesNotExist:
  78                         if self.passthrough:
  79                                 return self.passthrough.__getitem__(key)
  80                         raise KeyError
  81         def keys(self):
  82                 keys = set(self.queryset.values_list('key', flat=True).distinct())
  83                 if self.passthrough:
  84                         keys += set(self.passthrough.keys())
  85                 return list(keys)
  86
  87
  88 class Entity(models.Model):
  89         attribute_set = generic.GenericRelation(Attribute, content_type_field='entity_content_type', object_id_field='entity_object_id')
  90         relationship_set = generic.GenericRelation(Relationship, content_type_field='entity_content_type', object_id_field='entity_object_id')
  91
  92         @property
  93         def attributes(self):
  94                 return QuerySetMapper(self.attribute_set)
  95
  96         @property
  97         def relationships(self):
  98                 return QuerySetMapper(self.relationship_set)
  99
 100         class Meta:
 101                 abstract = True
 102
 103
 104 class Collection(models.Model):
 105         name = models.CharField(max_length=255)
 106         description = models.TextField(blank=True, null=True)
 107
 108
 109 class CollectionMemberManager(models.Manager):
 110         use_for_related_fields = True
 111
 112         def with_model(self, model):
 113                 return model._default_manager.filter(pk__in=self.filter(member_content_type=ContentType.objects.get_for_model(model)).values_list('member_object_id', flat=True))
 114
 115
 116 class CollectionMember(models.Model):
 117         objects = CollectionMemberManager()
 118         collection = models.ForeignKey(Collection, related_name='members')
 119         index = models.PositiveIntegerField(verbose_name='Index', help_text='This will determine the ordering of the item within the collection. (Optional)', null=True, blank=True)
 120         member_content_type = models.ForeignKey(ContentType, verbose_name='Member type')
 121         member_object_id = models.PositiveIntegerField(verbose_name='Member ID')
 122         member = generic.GenericForeignKey('member_content_type', 'member_object_id')
 123
 124
 125 class TreeManager(models.Manager):
 126         use_for_related_fields = True
 127
 128         def roots(self):
 129                 return self.filter(parent__isnull=True)
 130
 131         def get_with_path(self, path, root=None, absolute_result=True, pathsep='/'):
 132                 """
 133                 Returns the object with the path, or None if there is no object with that path,
 134                 unless absolute_result is set to False, in which case it returns a tuple containing
 135                 the deepest object found along the path, and the remainder of the path after that
 136                 object as a string (or None in the case that there is no remaining path).
 137                 """
 138                 slugs = path.split(pathsep)
 139                 obj = root
 140                 remaining_slugs = list(slugs)
 141                 remainder = None
 142                 for slug in slugs:
 143                         remaining_slugs.remove(slug)
 144                         if slug: # ignore blank slugs, handles for multiple consecutive pathseps
 145                                 try:
 146                                         obj = self.get(slug__exact=slug, parent__exact=obj)
 147                                 except self.model.DoesNotExist:
 148                                         if absolute_result:
 149                                                 obj = None
 150                                         remaining_slugs.insert(0, slug)
 151                                         remainder = pathsep.join(remaining_slugs)
 152                                         break
 153                 if obj:
 154                         if absolute_result:
 155                                 return obj
 156                         else:
 157                                 return (obj, remainder)
 158                 raise self.model.DoesNotExist('%s matching query does not exist.' % self.model._meta.object_name)
 159
 160
 161 class TreeModel(models.Model):
 162         objects = TreeManager()
 163         parent = models.ForeignKey('self', related_name='children', null=True, blank=True)
 164         slug = models.SlugField()
 165
 166         def get_path(self, pathsep='/', field='slug'):
 167                 path = getattr(self, field, '?')
 168                 parent = self.parent
 169                 while parent:
 170                         path = getattr(parent, field, '?') + pathsep + path
 171                         parent = parent.parent
 172                 return path
 173         path = property(get_path)
 174
 175         def __unicode__(self):
 176                 return self.path
 177
 178         class Meta:
 179                 abstract = True
 180
 181
 182 class TreeEntity(TreeModel, Entity):
 183         @property
 184         def attributes(self):
 185                 if self.parent:
 186                         return QuerySetMapper(self.attribute_set, passthrough=self.parent.attributes)
 187                 return super(TreeEntity, self).attributes
 188
 189         @property
 190         def relationships(self):
 191                 if self.parent:
 192                         return QuerySetMapper(self.relationship_set, passthrough=self.parent.relationships)
 193                 return super(TreeEntity, self).relationships
 194
 195         class Meta:
 196                 abstract = True
 197
 198
 199 class InheritableTreeEntity(TreeEntity):
 200         instance_type = models.ForeignKey(ContentType, editable=False)
 201
 202         def save(self, force_insert=False, force_update=False):
 203                 if not hasattr(self, 'instance_type_ptr'):
 204                         self.instance_type = ContentType.objects.get_for_model(self.__class__)
 205                 super(InheritableTreeEntity, self).save(force_insert, force_update)
 206
 207         @property
 208         def instance(self):
 209                 return self.instance_type.get_object_for_this_type(id=self.id)
 210
 211         def get_path(self, pathsep='/', field='slug'):
 212                 path = getattr(self.instance, field, '?')
 213                 parent = self.parent
 214                 while parent:
 215                         path = getattr(parent.instance, field, '?') + pathsep + path
 216                         parent = parent.parent
 217                 return path
 218         path = property(get_path)
 219
 220         @property
 221         def attributes(self):
 222                 if self.parent:
 223                         return QuerySetMapper(self.instance.attribute_set, passthrough=self.parent.instance.attributes)
 224                 return QuerySetMapper(self.instance.attribute_set)
 225
 226         @property
 227         def relationships(self):
 228                 if self.parent:
 229                         return QuerySetMapper(self.instance.relationship_set, passthrough=self.parent.instance.relationships)
 230                 return QuerySetMapper(self.instance.relationship_set)
 231
 232         class Meta:
 233                 abstract = True
 234
 235
 236 class Node(InheritableTreeEntity):
 237         accepts_subpath = False
 238
 239         def render_to_response(self, request, path=None, subpath=None):
 240                 return HttpResponseServerError()
 241
 242
 243 class MultiNode(Node):
 244         accepts_subpath = True
 245
 246         urlpatterns = []
 247
 248         def render_to_response(self, request, path=None, subpath=None):
 249                 if not subpath:
 250                         subpath = ""
 251                 subpath = "/" + subpath
 252                 from django.core.urlresolvers import resolve
 253                 view, args, kwargs = resolve(subpath, urlconf=self)
 254                 return view(request, *args, **kwargs)
 255
 256         class Meta:
 257                 abstract = True
 258
 259
 260 class Redirect(Node):
 261         STATUS_CODES = (
 262                 (302, 'Temporary'),
 263                 (301, 'Permanent'),
 264         )
 265         target = models.URLField(help_text='Must be a valid, absolute URL (i.e. http://)')
 266         status_code = models.IntegerField(choices=STATUS_CODES, default=302, verbose_name='redirect type')
 267
 268         def render_to_response(self, request, path=None, subpath=None):
 269                 response = HttpResponseRedirect(self.target)
 270                 response.status_code = self.status_code
 271                 return response
 272
 273
 274 class File(Node):
 275         """ For storing arbitrary files """
 276         mimetype = models.CharField(max_length=255)
 277         file = models.FileField(upload_to='philo/files/%Y/%m/%d')
 278
 279         def render_to_response(self, request, path=None, subpath=None):
 280                 wrapper = FileWrapper(self.file)
 281                 response = HttpResponse(wrapper, content_type=self.mimetype)
 282                 response['Content-Length'] = self.file.size
 283                 return response
 284
 285
 286 class Template(TreeModel):
 287         name = models.CharField(max_length=255)
 288         documentation = models.TextField(null=True, blank=True)
 289         mimetype = models.CharField(max_length=255, null=True, blank=True,
 290             help_text='Default: %s' % settings.DEFAULT_CONTENT_TYPE)
 291         code = models.TextField(verbose_name='django template code')
 292
 293         @property
 294         def origin(self):
 295                 return 'philo.models.Template: ' + self.path
 296
 297         @property
 298         def django_template(self):
 299                 return DjangoTemplate(self.code)
 300
 301         @property
 302         def containers(self):
 303                 """
 304                 Returns a tuple where the first item is a list of names of contentlets referenced by containers,
 305                 and the second item is a list of tuples of names and contenttypes of contentreferences referenced by containers.
 306                 This will break if there is a recursive extends or includes in the template code.
 307                 Due to the use of an empty Context, any extends or include tags with dynamic arguments probably won't work.
 308                 """
 309                 def container_nodes(template):
 310                         def nodelist_container_nodes(nodelist):
 311                                 nodes = []
 312                                 for node in nodelist:
 313                                         try:
 314                                                 for nodelist_name in ('nodelist', 'nodelist_loop', 'nodelist_empty', 'nodelist_true', 'nodelist_false'):
 315                                                         if hasattr(node, nodelist_name):
 316                                                                 nodes.extend(nodelist_container_nodes(getattr(node, nodelist_name)))
 317                                                 if isinstance(node, ContainerNode):
 318                                                         nodes.append(node)
 319                                                 elif isinstance(node, ExtendsNode):
 320                                                         extended_template = node.get_parent(Context())
 321                                                         if extended_template:
 322                                                                 nodes.extend(container_nodes(extended_template))
 323                                                 elif isinstance(node, ConstantIncludeNode):
 324                                                         included_template = node.template
 325                                                         if included_template:
 326                                                                 nodes.extend(container_nodes(included_template))
 327                                                 elif isinstance(node, IncludeNode):
 328                                                         included_template = get_template(node.template_name.resolve(Context()))
 329                                                         if included_template:
 330                                                                 nodes.extend(container_nodes(included_template))
 331                                         except:
 332                                                 pass # fail for this node
 333                                 return nodes
 334                         return nodelist_container_nodes(template.nodelist)
 335                 all_nodes = container_nodes(self.django_template)
 336                 contentlet_node_names = set([node.name for node in all_nodes if not node.references])
 337                 contentreference_node_names = []
 338                 contentreference_node_specs = []
 339                 for node in all_nodes:
 340                         if node.references and node.name not in contentreference_node_names:
 341                                 contentreference_node_specs.append((node.name, node.references))
 342                                 contentreference_node_names.append(node.name)
 343                 return contentlet_node_names, contentreference_node_specs
 344
 345         def __unicode__(self):
 346                 return self.get_path(u' › ', 'name')
 347
 348         @staticmethod
 349         @fattr(is_usable=True)
 350         def loader(template_name, template_dirs=None): # load_template_source
 351                 try:
 352                         template = Template.objects.get_with_path(template_name)
 353                 except Template.DoesNotExist:
 354                         raise TemplateDoesNotExist(template_name)
 355                 return (template.code, template.origin)
 356
 357
 358 class Page(Node):
 359         """
 360         Represents an HTML page. The page will have a number of related Contentlets
 361         depending on the template selected - but these will appear only after the
 362         page has been saved with that template.
 363         """
 364         template = models.ForeignKey(Template, related_name='pages')
 365         title = models.CharField(max_length=255)
 366
 367         def render_to_response(self, request, path=None, subpath=None):
 368                 return HttpResponse(self.template.django_template.render(RequestContext(request, {'page': self})), mimetype=self.template.mimetype)
 369
 370         def __unicode__(self):
 371                 return self.get_path(u' › ', 'title')
 372
 373
 374 # the following line enables the selection of a node as the root for a given django.contrib.sites Site object
 375 models.ForeignKey(Node, related_name='sites', null=True, blank=True).contribute_to_class(Site, 'root_node')
 376
 377
 378 class Contentlet(models.Model):
 379         page = models.ForeignKey(Page, related_name='contentlets')
 380         name = models.CharField(max_length=255)
 381         content = models.TextField()
 382         dynamic = models.BooleanField(default=False)
 383
 384
 385 class ContentReference(models.Model):
 386         page = models.ForeignKey(Page, related_name='contentreferences')
 387         name = models.CharField(max_length=255)
 388         content_type = models.ForeignKey(ContentType, verbose_name='Content type')
 389         content_id = models.PositiveIntegerField(verbose_name='Content ID')
 390         content = generic.GenericForeignKey('content_type', 'content_id')
 391
 392
 393 register_templatetags('philo.templatetags.containers')
 394
 395
 396 register_value_model(User)
 397 register_value_model(Group)
 398 register_value_model(Site)
 399 register_value_model(Collection)
 400 register_value_model(Template)
 401 register_value_model(Page)