+from django import forms
from django.db import models
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes import generic
-from django.utils import simplejson as json
from django.core.exceptions import ObjectDoesNotExist
+from django.core.validators import RegexValidator
+from django.utils import simplejson as json
+from django.utils.encoding import smart_str
+from philo.exceptions import AncestorDoesNotExist
+from philo.models.fields import JSONField
+from philo.utils import ContentTypeRegistryLimiter, ContentTypeSubclassLimiter
+from philo.signals import entity_class_prepared
+from philo.validators import json_validator
from UserDict import DictMixin
+from mptt.models import MPTTModel, MPTTModelBase, MPTTOptions
+
+
+class Tag(models.Model):
+ name = models.CharField(max_length=255)
+ slug = models.SlugField(max_length=255, unique=True)
+
+ def __unicode__(self):
+ return self.name
+
+ class Meta:
+ app_label = 'philo'
+ ordering = ('name',)
+
+
+class Titled(models.Model):
+ title = models.CharField(max_length=255)
+ slug = models.SlugField(max_length=255)
+
+ def __unicode__(self):
+ return self.title
+
+ class Meta:
+ abstract = True
+
+
+value_content_type_limiter = ContentTypeRegistryLimiter()
def register_value_model(model):
- pass
+ value_content_type_limiter.register_class(model)
def unregister_value_model(model):
- pass
+ value_content_type_limiter.unregister_class(model)
-class Attribute(models.Model):
- entity_content_type = models.ForeignKey(ContentType, verbose_name='Entity type')
- entity_object_id = models.PositiveIntegerField(verbose_name='Entity ID')
- entity = generic.GenericForeignKey('entity_content_type', 'entity_object_id')
- key = models.CharField(max_length=255)
- json_value = models.TextField(verbose_name='Value (JSON)', help_text='This value must be valid JSON.')
+class AttributeValue(models.Model):
+ attribute_set = generic.GenericRelation('Attribute', content_type_field='value_content_type', object_id_field='value_object_id')
+
+ @property
+ def attribute(self):
+ return self.attribute_set.all()[0]
+
+ def apply_data(self, data):
+ raise NotImplementedError
+
+ def value_formfield(self, **kwargs):
+ raise NotImplementedError
+
+ def __unicode__(self):
+ return unicode(self.value)
+
+ class Meta:
+ abstract = True
+
+
+attribute_value_limiter = ContentTypeSubclassLimiter(AttributeValue)
+
+
+class JSONValue(AttributeValue):
+ value = JSONField() #verbose_name='Value (JSON)', help_text='This value must be valid JSON.')
+
+ def __unicode__(self):
+ return smart_str(self.value)
+
+ def value_formfield(self, **kwargs):
+ kwargs['initial'] = self.value_json
+ return self._meta.get_field('value').formfield(**kwargs)
+
+ def apply_data(self, cleaned_data):
+ self.value = cleaned_data.get('value', None)
+
+ class Meta:
+ app_label = 'philo'
+
+
+class ForeignKeyValue(AttributeValue):
+ content_type = models.ForeignKey(ContentType, limit_choices_to=value_content_type_limiter, verbose_name='Value type', null=True, blank=True)
+ object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True)
+ value = generic.GenericForeignKey()
+
+ def value_formfield(self, form_class=forms.ModelChoiceField, **kwargs):
+ if self.content_type is None:
+ return None
+ kwargs.update({'initial': self.object_id, 'required': False})
+ return form_class(self.content_type.model_class()._default_manager.all(), **kwargs)
+
+ def apply_data(self, cleaned_data):
+ if 'value' in cleaned_data and cleaned_data['value'] is not None:
+ self.value = cleaned_data['value']
+ else:
+ self.content_type = cleaned_data.get('content_type', None)
+ # If there is no value set in the cleaned data, clear the stored value.
+ self.object_id = None
+
+ class Meta:
+ app_label = 'philo'
+
+
+class ManyToManyValue(AttributeValue):
+ content_type = models.ForeignKey(ContentType, limit_choices_to=value_content_type_limiter, verbose_name='Value type', null=True, blank=True)
+ values = models.ManyToManyField(ForeignKeyValue, blank=True, null=True)
+
+ def get_object_id_list(self):
+ if not self.values.count():
+ return []
+ else:
+ return self.values.values_list('object_id', flat=True)
def get_value(self):
- return json.loads(self.json_value)
+ if self.content_type is None:
+ return None
+
+ return self.content_type.model_class()._default_manager.filter(id__in=self.get_object_id_list())
def set_value(self, value):
- self.json_value = json.dumps(value)
+ # Value is probably a queryset - but allow any iterable.
+
+ # These lines shouldn't be necessary; however, if value is an EmptyQuerySet,
+ # the code (specifically the object_id__in query) won't work without them. Unclear why...
+ if not value:
+ value = []
+
+ # Before we can fiddle with the many-to-many to foreignkeyvalues, we need
+ # a pk.
+ if self.pk is None:
+ self.save()
+
+ if isinstance(value, models.query.QuerySet):
+ value = value.values_list('id', flat=True)
+
+ self.values.filter(~models.Q(object_id__in=value)).delete()
+ current = self.get_object_id_list()
+
+ for v in value:
+ if v in current:
+ continue
+ self.values.create(content_type=self.content_type, object_id=v)
- def delete_value(self):
- self.json_value = json.dumps(None)
+ value = property(get_value, set_value)
- value = property(get_value, set_value, delete_value)
+ def value_formfield(self, form_class=forms.ModelMultipleChoiceField, **kwargs):
+ if self.content_type is None:
+ return None
+ kwargs.update({'initial': self.get_object_id_list(), 'required': False})
+ return form_class(self.content_type.model_class()._default_manager.all(), **kwargs)
- def __unicode__(self):
- return u'"%s": %s' % (self.key, self.value)
+ def apply_data(self, cleaned_data):
+ if 'value' in cleaned_data and cleaned_data['value'] is not None:
+ self.value = cleaned_data['value']
+ else:
+ self.content_type = cleaned_data.get('content_type', None)
+ # If there is no value set in the cleaned data, clear the stored value.
+ self.value = []
class Meta:
app_label = 'philo'
-class Relationship(models.Model):
- entity_content_type = models.ForeignKey(ContentType, related_name='relationship_entity_set', verbose_name='Entity type')
+class Attribute(models.Model):
+ entity_content_type = models.ForeignKey(ContentType, related_name='attribute_entity_set', verbose_name='Entity type')
entity_object_id = models.PositiveIntegerField(verbose_name='Entity ID')
entity = generic.GenericForeignKey('entity_content_type', 'entity_object_id')
- key = models.CharField(max_length=255)
- value_content_type = models.ForeignKey(ContentType, related_name='relationship_value_set', verbose_name='Value type')
- value_object_id = models.PositiveIntegerField(verbose_name='Value ID')
+
+ 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)
+ value_object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True)
value = generic.GenericForeignKey('value_content_type', 'value_object_id')
+ key = models.CharField(max_length=255, validators=[RegexValidator("\w+")], help_text="Must contain one or more alphanumeric characters or underscores.")
+
def __unicode__(self):
return u'"%s": %s' % (self.key, self.value)
class Meta:
app_label = 'philo'
+ unique_together = (('key', 'entity_content_type', 'entity_object_id'), ('value_content_type', 'value_object_id'))
class QuerySetMapper(object, DictMixin):
def __init__(self, queryset, passthrough=None):
self.queryset = queryset
self.passthrough = passthrough
+
def __getitem__(self, key):
try:
- return self.queryset.get(key__exact=key).value
+ value = self.queryset.get(key__exact=key).value
except ObjectDoesNotExist:
- if self.passthrough:
+ if self.passthrough is not None:
return self.passthrough.__getitem__(key)
raise KeyError
+ else:
+ if value is not None:
+ return value.value
+ return value
+
def keys(self):
keys = set(self.queryset.values_list('key', flat=True).distinct())
- if self.passthrough:
- keys += set(self.passthrough.keys())
+ if self.passthrough is not None:
+ keys |= set(self.passthrough.keys())
return list(keys)
+class EntityOptions(object):
+ def __init__(self, options):
+ if options is not None:
+ for key, value in options.__dict__.items():
+ setattr(self, key, value)
+ if not hasattr(self, 'proxy_fields'):
+ self.proxy_fields = []
+
+ def add_proxy_field(self, proxy_field):
+ self.proxy_fields.append(proxy_field)
+
+
+class EntityBase(models.base.ModelBase):
+ def __new__(cls, name, bases, attrs):
+ new = super(EntityBase, cls).__new__(cls, name, bases, attrs)
+ entity_options = attrs.pop('EntityMeta', None)
+ setattr(new, '_entity_meta', EntityOptions(entity_options))
+ entity_class_prepared.send(sender=new)
+ return new
+
+
class Entity(models.Model):
+ __metaclass__ = EntityBase
+
attribute_set = generic.GenericRelation(Attribute, content_type_field='entity_content_type', object_id_field='entity_object_id')
- relationship_set = generic.GenericRelation(Relationship, content_type_field='entity_content_type', object_id_field='entity_object_id')
@property
def attributes(self):
- return QuerySetMapper(self.attribute_set)
+ return QuerySetMapper(self.attribute_set.all())
@property
- def relationships(self):
- return QuerySetMapper(self.relationship_set)
+ def _added_attribute_registry(self):
+ if not hasattr(self, '_real_added_attribute_registry'):
+ self._real_added_attribute_registry = {}
+ return self._real_added_attribute_registry
+
+ @property
+ def _removed_attribute_registry(self):
+ if not hasattr(self, '_real_removed_attribute_registry'):
+ self._real_removed_attribute_registry = []
+ return self._real_removed_attribute_registry
+
+ def save(self, *args, **kwargs):
+ super(Entity, self).save(*args, **kwargs)
+
+ for key in self._removed_attribute_registry:
+ self.attribute_set.filter(key__exact=key).delete()
+ del self._removed_attribute_registry[:]
+
+ for field, value in self._added_attribute_registry.items():
+ try:
+ attribute = self.attribute_set.get(key__exact=field.key)
+ except Attribute.DoesNotExist:
+ attribute = Attribute()
+ attribute.entity = self
+ attribute.key = field.key
+
+ field.set_attribute_value(attribute, value)
+ attribute.save()
+ self._added_attribute_registry.clear()
class Meta:
abstract = True
- app_label = 'philo'
class TreeManager(models.Manager):
use_for_related_fields = True
- def roots(self):
- return self.filter(parent__isnull=True)
-
- def get_with_path(self, path, root=None, absolute_result=True, pathsep='/'):
+ def get_with_path(self, path, root=None, absolute_result=True, pathsep='/', field='slug'):
"""
- Returns the object with the path, or None if there is no object with that path,
- unless absolute_result is set to False, in which case it returns a tuple containing
- the deepest object found along the path, and the remainder of the path after that
- object as a string (or None in the case that there is no remaining path).
+ Returns the object with the path, unless absolute_result is set to False, in which
+ case it returns a tuple containing the deepest object found along the path, and the
+ remainder of the path after that object as a string (or None if there is no remaining
+ path). Raises a DoesNotExist exception if no object is found with the given path.
+
+ If the path you're searching for is known to exist, it is always faster to use
+ absolute_result=True - unless the path depth is over ~40, in which case the high cost
+ of the absolute query makes a binary search (i.e. non-absolute) faster.
"""
- slugs = path.split(pathsep)
- obj = root
- remaining_slugs = list(slugs)
- remainder = None
- for slug in slugs:
- remaining_slugs.remove(slug)
- if slug: # ignore blank slugs, handles for multiple consecutive pathseps
+ # Note: SQLite allows max of 64 tables in one join. That means the binary search will
+ # only work on paths with a max depth of 127 and the absolute fetch will only work
+ # to a max depth of (surprise!) 63. Although this could be handled, chances are your
+ # tree structure won't be that deep.
+ segments = path.split(pathsep)
+
+ # Check for a trailing pathsep so we can restore it later.
+ trailing_pathsep = False
+ if segments[-1] == '':
+ trailing_pathsep = True
+
+ # Clean out blank segments. Handles multiple consecutive pathseps.
+ while True:
+ try:
+ segments.remove('')
+ except ValueError:
+ break
+
+ # Special-case a lack of segments. No queries necessary.
+ if not segments:
+ if root is not None:
+ if absolute_result:
+ return root
+ return root, None
+ else:
+ raise self.model.DoesNotExist('%s matching query does not exist.' % self.model._meta.object_name)
+
+ def make_query_kwargs(segments, root):
+ kwargs = {}
+ prefix = ""
+ revsegs = list(segments)
+ revsegs.reverse()
+
+ for segment in revsegs:
+ kwargs["%s%s__exact" % (prefix, field)] = segment
+ prefix += "parent__"
+
+ if prefix:
+ kwargs[prefix[:-2]] = root
+
+ return kwargs
+
+ def build_path(segments):
+ path = pathsep.join(segments)
+ if trailing_pathsep and segments and segments[-1] != '':
+ path += pathsep
+ return path
+
+ def find_obj(segments, depth, deepest_found=None):
+ if deepest_found is None:
+ deepest_level = 0
+ elif root is None:
+ deepest_level = deepest_found.get_level() + 1
+ else:
+ deepest_level = deepest_found.get_level() - root.get_level()
+ try:
+ obj = self.get(**make_query_kwargs(segments[deepest_level:depth], deepest_found or root))
+ except self.model.DoesNotExist:
+ if not deepest_level and depth > 1:
+ # make sure there's a root node...
+ depth = 1
+ else:
+ # Try finding one with half the path since the deepest find.
+ depth = (deepest_level + depth)/2
+
+ if deepest_level == depth:
+ # This should happen if nothing is found with any part of the given path.
+ if root is not None and deepest_found is None:
+ return root, build_path(segments)
+ raise
+
+ return find_obj(segments, depth, deepest_found)
+ else:
+ # Yay! Found one!
+ if root is None:
+ deepest_level = obj.get_level() + 1
+ else:
+ deepest_level = obj.get_level() - root.get_level()
+
+ # Could there be a deeper one?
+ if obj.is_leaf_node():
+ return obj, build_path(segments[deepest_level:]) or None
+
+ depth += (len(segments) - depth)/2 or len(segments) - depth
+
+ if depth > deepest_level + obj.get_descendant_count():
+ depth = deepest_level + obj.get_descendant_count()
+
+ if deepest_level == depth:
+ return obj, build_path(segments[deepest_level:]) or None
+
try:
- obj = self.get(slug__exact=slug, parent__exact=obj)
+ return find_obj(segments, depth, obj)
except self.model.DoesNotExist:
- if absolute_result:
- obj = None
- remaining_slugs.insert(0, slug)
- remainder = pathsep.join(remaining_slugs)
- break
- if obj:
- if absolute_result:
- return obj
- else:
- return (obj, remainder)
- raise self.model.DoesNotExist('%s matching query does not exist.' % self.model._meta.object_name)
+ # Then this was the deepest.
+ return obj, build_path(segments[deepest_level:])
+
+ if absolute_result:
+ return self.get(**make_query_kwargs(segments, root))
+
+ # Try a modified binary search algorithm. Feed the root in so that query complexity
+ # can be reduced. It might be possible to weight the search towards the beginning
+ # of the path, since short paths are more likely, but how far forward? It would
+ # need to shift depending on len(segments) - perhaps logarithmically?
+ return find_obj(segments, len(segments)/2 or len(segments))
-class TreeModel(models.Model):
+class TreeModel(MPTTModel):
objects = TreeManager()
parent = models.ForeignKey('self', related_name='children', null=True, blank=True)
- slug = models.SlugField()
-
- def get_path(self, pathsep='/', field='slug'):
- path = getattr(self, field, '?')
- parent = self.parent
- while parent:
- path = getattr(parent, field, '?') + pathsep + path
- parent = parent.parent
- return path
+ slug = models.SlugField(max_length=255)
+
+ def get_path(self, root=None, pathsep='/', field='slug'):
+ if root == self:
+ return ''
+
+ if root is not None and not self.is_descendant_of(root):
+ raise AncestorDoesNotExist(root)
+
+ qs = self.get_ancestors()
+
+ if root is not None:
+ qs = qs.filter(**{'%s__gt' % self._mptt_meta.level_attr: root.get_level()})
+
+ return pathsep.join([getattr(parent, field, '?') for parent in list(qs) + [self]])
path = property(get_path)
def __unicode__(self):
return self.path
class Meta:
+ unique_together = (('parent', 'slug'),)
abstract = True
- app_label = 'philo'
-class TreeEntity(TreeModel, Entity):
- @property
- def attributes(self):
- if self.parent:
- return QuerySetMapper(self.attribute_set, passthrough=self.parent.attributes)
- return super(TreeEntity, self).attributes
-
- @property
- def relationships(self):
- if self.parent:
- return QuerySetMapper(self.relationship_set, passthrough=self.parent.relationships)
- return super(TreeEntity, self).relationships
-
- class Meta:
- abstract = True
- app_label = 'philo'
+class TreeEntityBase(MPTTModelBase, EntityBase):
+ def __new__(meta, name, bases, attrs):
+ attrs['_mptt_meta'] = MPTTOptions(attrs.pop('MPTTMeta', None))
+ cls = EntityBase.__new__(meta, name, bases, attrs)
+
+ return meta.register(cls)
-class InheritableTreeEntity(TreeEntity):
- instance_type = models.ForeignKey(ContentType, editable=False)
-
- def save(self, force_insert=False, force_update=False):
- if not hasattr(self, 'instance_type_ptr'):
- self.instance_type = ContentType.objects.get_for_model(self.__class__)
- super(InheritableTreeEntity, self).save(force_insert, force_update)
-
- @property
- def instance(self):
- try:
- return self.instance_type.get_object_for_this_type(id=self.id)
- except:
- return None
-
- def get_path(self, pathsep='/', field='slug'):
- path = getattr(self.instance, field, getattr(self.instance, 'slug', '?'))
- parent = self.parent
- while parent:
- path = getattr(parent.instance, field, getattr(parent.instance, 'slug', '?')) + pathsep + path
- parent = parent.parent
- return path
- path = property(get_path)
+class TreeEntity(Entity, TreeModel):
+ __metaclass__ = TreeEntityBase
@property
def attributes(self):
if self.parent:
- return QuerySetMapper(self.instance.attribute_set, passthrough=self.parent.instance.attributes)
- return QuerySetMapper(self.instance.attribute_set)
-
- @property
- def relationships(self):
- if self.parent:
- return QuerySetMapper(self.instance.relationship_set, passthrough=self.parent.instance.relationships)
- return QuerySetMapper(self.instance.relationship_set)
+ return QuerySetMapper(self.attribute_set.all(), passthrough=self.parent.attributes)
+ return super(TreeEntity, self).attributes
class Meta:
- abstract = True
- app_label = 'philo'
\ No newline at end of file
+ abstract = True
\ No newline at end of file