1 from django import forms
2 from django.db import models
3 from django.contrib.contenttypes.models import ContentType
4 from django.contrib.contenttypes import generic
5 from django.utils import simplejson as json
6 from django.core.exceptions import ObjectDoesNotExist
7 from philo.exceptions import AncestorDoesNotExist
8 from philo.models.fields import JSONField
9 from philo.utils import ContentTypeRegistryLimiter, ContentTypeSubclassLimiter
10 from philo.signals import entity_class_prepared
11 from philo.validators import json_validator
12 from UserDict import DictMixin
15 class Tag(models.Model):
16 name = models.CharField(max_length=255)
17 slug = models.SlugField(max_length=255, unique=True)
19 def __unicode__(self):
26 class Titled(models.Model):
27 title = models.CharField(max_length=255)
28 slug = models.SlugField(max_length=255)
30 def __unicode__(self):
37 value_content_type_limiter = ContentTypeRegistryLimiter()
40 def register_value_model(model):
41 value_content_type_limiter.register_class(model)
44 def unregister_value_model(model):
45 value_content_type_limiter.unregister_class(model)
48 class AttributeValue(models.Model):
49 attribute_set = generic.GenericRelation('Attribute', content_type_field='value_content_type', object_id_field='value_object_id')
53 return self.attribute_set.all()[0]
55 def apply_data(self, data):
56 raise NotImplementedError
58 def value_formfield(self, **kwargs):
59 raise NotImplementedError
61 def __unicode__(self):
62 return unicode(self.value)
68 attribute_value_limiter = ContentTypeSubclassLimiter(AttributeValue)
71 class JSONValue(AttributeValue):
72 value = JSONField() #verbose_name='Value (JSON)', help_text='This value must be valid JSON.')
74 def __unicode__(self):
75 return self.value_json
77 def value_formfield(self, **kwargs):
78 kwargs['initial'] = self.value_json
79 return self._meta.get_field('value').formfield(**kwargs)
81 def apply_data(self, cleaned_data):
82 self.value = cleaned_data.get('value', None)
88 class ForeignKeyValue(AttributeValue):
89 content_type = models.ForeignKey(ContentType, limit_choices_to=value_content_type_limiter, verbose_name='Value type', null=True, blank=True)
90 object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True)
91 value = generic.GenericForeignKey()
93 def value_formfield(self, form_class=forms.ModelChoiceField, **kwargs):
94 if self.content_type is None:
96 kwargs.update({'initial': self.object_id, 'required': False})
97 return form_class(self.content_type.model_class()._default_manager.all(), **kwargs)
99 def apply_data(self, cleaned_data):
100 if 'value' in cleaned_data and cleaned_data['value'] is not None:
101 self.value = cleaned_data['value']
103 self.content_type = cleaned_data.get('content_type', None)
104 # If there is no value set in the cleaned data, clear the stored value.
105 self.object_id = None
111 class ManyToManyValue(AttributeValue):
112 content_type = models.ForeignKey(ContentType, limit_choices_to=value_content_type_limiter, verbose_name='Value type', null=True, blank=True)
113 values = models.ManyToManyField(ForeignKeyValue, blank=True, null=True)
115 def get_object_id_list(self):
116 if not self.values.count():
119 return self.values.values_list('object_id', flat=True)
122 if self.content_type is None:
125 return self.content_type.model_class()._default_manager.filter(id__in=self.get_object_id_list())
127 def set_value(self, value):
128 # Value is probably a queryset - but allow any iterable.
130 # These lines shouldn't be necessary; however, if value is an EmptyQuerySet,
131 # the code (specifically the object_id__in query) won't work without them. Unclear why...
135 # Before we can fiddle with the many-to-many to foreignkeyvalues, we need
140 if isinstance(value, models.query.QuerySet):
141 value = value.values_list('id', flat=True)
143 self.values.filter(~models.Q(object_id__in=value)).delete()
144 current = self.get_object_id_list()
149 self.values.create(content_type=self.content_type, object_id=v)
151 value = property(get_value, set_value)
153 def value_formfield(self, form_class=forms.ModelMultipleChoiceField, **kwargs):
154 if self.content_type is None:
156 kwargs.update({'initial': self.get_object_id_list(), 'required': False})
157 return form_class(self.content_type.model_class()._default_manager.all(), **kwargs)
159 def apply_data(self, cleaned_data):
160 if 'value' in cleaned_data and cleaned_data['value'] is not None:
161 self.value = cleaned_data['value']
163 self.content_type = cleaned_data.get('content_type', None)
164 # If there is no value set in the cleaned data, clear the stored value.
171 class Attribute(models.Model):
172 entity_content_type = models.ForeignKey(ContentType, related_name='attribute_entity_set', verbose_name='Entity type')
173 entity_object_id = models.PositiveIntegerField(verbose_name='Entity ID')
174 entity = generic.GenericForeignKey('entity_content_type', 'entity_object_id')
176 value_content_type = models.ForeignKey(ContentType, related_name='attribute_value_set', limit_choices_to=attribute_value_limiter, verbose_name='Value type', null=True, blank=True)
177 value_object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True)
178 value = generic.GenericForeignKey('value_content_type', 'value_object_id')
180 key = models.CharField(max_length=255)
182 def __unicode__(self):
183 return u'"%s": %s' % (self.key, self.value)
187 unique_together = (('key', 'entity_content_type', 'entity_object_id'), ('value_content_type', 'value_object_id'))
190 class QuerySetMapper(object, DictMixin):
191 def __init__(self, queryset, passthrough=None):
192 self.queryset = queryset
193 self.passthrough = passthrough
195 def __getitem__(self, key):
197 value = self.queryset.get(key__exact=key).value
198 except ObjectDoesNotExist:
199 if self.passthrough is not None:
200 return self.passthrough.__getitem__(key)
203 if value is not None:
208 keys = set(self.queryset.values_list('key', flat=True).distinct())
209 if self.passthrough is not None:
210 keys |= set(self.passthrough.keys())
214 class EntityOptions(object):
215 def __init__(self, options):
216 if options is not None:
217 for key, value in options.__dict__.items():
218 setattr(self, key, value)
219 if not hasattr(self, 'proxy_fields'):
220 self.proxy_fields = []
222 def add_proxy_field(self, proxy_field):
223 self.proxy_fields.append(proxy_field)
226 class EntityBase(models.base.ModelBase):
227 def __new__(cls, name, bases, attrs):
228 new = super(EntityBase, cls).__new__(cls, name, bases, attrs)
229 entity_options = attrs.pop('EntityMeta', None)
230 setattr(new, '_entity_meta', EntityOptions(entity_options))
231 entity_class_prepared.send(sender=new)
235 class Entity(models.Model):
236 __metaclass__ = EntityBase
238 attribute_set = generic.GenericRelation(Attribute, content_type_field='entity_content_type', object_id_field='entity_object_id')
241 def attributes(self):
242 return QuerySetMapper(self.attribute_set.all())
245 def _added_attribute_registry(self):
246 if not hasattr(self, '_real_added_attribute_registry'):
247 self._real_added_attribute_registry = {}
248 return self._real_added_attribute_registry
251 def _removed_attribute_registry(self):
252 if not hasattr(self, '_real_removed_attribute_registry'):
253 self._real_removed_attribute_registry = []
254 return self._real_removed_attribute_registry
256 def save(self, *args, **kwargs):
257 super(Entity, self).save(*args, **kwargs)
259 for key in self._removed_attribute_registry:
260 self.attribute_set.filter(key__exact=key).delete()
261 del self._removed_attribute_registry[:]
263 for field, value in self._added_attribute_registry.items():
265 attribute = self.attribute_set.get(key__exact=field.key)
266 except Attribute.DoesNotExist:
267 attribute = Attribute()
268 attribute.entity = self
269 attribute.key = field.key
271 field.set_attribute_value(attribute, value)
273 self._added_attribute_registry.clear()
279 class TreeManager(models.Manager):
280 use_for_related_fields = True
283 return self.filter(parent__isnull=True)
285 def get_with_path(self, path, root=None, absolute_result=True, pathsep='/'):
287 Returns the object with the path, or None if there is no object with that path,
288 unless absolute_result is set to False, in which case it returns a tuple containing
289 the deepest object found along the path, and the remainder of the path after that
290 object as a string (or None in the case that there is no remaining path).
292 slugs = path.split(pathsep)
294 remaining_slugs = list(slugs)
297 remaining_slugs.remove(slug)
298 if slug: # ignore blank slugs, handles for multiple consecutive pathseps
300 obj = self.get(slug__exact=slug, parent__exact=obj)
301 except self.model.DoesNotExist:
304 remaining_slugs.insert(0, slug)
305 remainder = pathsep.join(remaining_slugs)
311 return (obj, remainder)
312 raise self.model.DoesNotExist('%s matching query does not exist.' % self.model._meta.object_name)
315 class TreeModel(models.Model):
316 objects = TreeManager()
317 parent = models.ForeignKey('self', related_name='children', null=True, blank=True)
318 slug = models.SlugField(max_length=255)
320 def has_ancestor(self, ancestor):
323 if parent == ancestor:
325 parent = parent.parent
328 def get_path(self, root=None, pathsep='/', field='slug'):
329 if root is not None and not self.has_ancestor(root):
330 raise AncestorDoesNotExist(root)
332 path = getattr(self, field, '?')
334 while parent and parent != root:
335 path = getattr(parent, field, '?') + pathsep + path
336 parent = parent.parent
338 path = property(get_path)
340 def __unicode__(self):
344 unique_together = (('parent', 'slug'),)
348 class TreeEntity(Entity, TreeModel):
350 def attributes(self):
352 return QuerySetMapper(self.attribute_set.all(), passthrough=self.parent.attributes)
353 return super(TreeEntity, self).attributes