X-Git-Url: http://git.ithinksw.org/philo.git/blobdiff_plain/2f7a76a00f2bcae2f67459b7fd86806278ef9b66..ca2138fef978345b9076a2f855ed434a0bac65e1:/models/base.py?ds=sidebyside

diff --git a/models/base.py b/models/base.py
index 291fe70..202c2f3 100644
--- a/models/base.py
+++ b/models/base.py
@@ -1,35 +1,38 @@
+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 philo.utils import ContentTypeRegistryLimiter
+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 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.')
-	
-	def get_value(self):
-		return json.loads(self.json_value)
+class Tag(models.Model):
+	name = models.CharField(max_length=255)
+	slug = models.SlugField(max_length=255, unique=True)
 	
-	def set_value(self, value):
-		self.json_value = json.dumps(value)
-	
-	def delete_value(self):
-		self.json_value = json.dumps(None)
+	def __unicode__(self):
+		return self.name
 	
-	value = property(get_value, set_value, delete_value)
+	class Meta:
+		app_label = 'philo'
+
+
+class Titled(models.Model):
+	title = models.CharField(max_length=255)
+	slug = models.SlugField(max_length=255)
 	
 	def __unicode__(self):
-		return u'"%s": %s' % (self.key, self.value)
+		return self.title
 	
 	class Meta:
-		app_label = 'philo'
+		abstract = True
 
 
 value_content_type_limiter = ContentTypeRegistryLimiter()
@@ -43,106 +46,374 @@ def unregister_value_model(model):
 	value_content_type_limiter.unregister_class(model)
 
 
+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 self.value_json
+	
+	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):
+		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):
+		# 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)
+	
+	value = property(get_value, set_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 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', limit_choices_to=value_content_type_limiter, 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)
+	
 	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 _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 relationships(self):
-		return QuerySetMapper(self.relationship_set)
+	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.
+					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(level__gt=root.level)
+		
+		return pathsep.join([getattr(parent, field, '?') for parent in list(qs) + [self]])
 	path = property(get_path)
 	
 	def __unicode__(self):
@@ -151,22 +422,24 @@ class TreeModel(models.Model):
 	class Meta:
 		unique_together = (('parent', 'slug'),)
 		abstract = True
-		app_label = 'philo'
 
 
-class TreeEntity(TreeModel, Entity):
+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 TreeEntity(Entity, TreeModel):
+	__metaclass__ = TreeEntityBase
+	
 	@property
 	def attributes(self):
 		if self.parent:
-			return QuerySetMapper(self.attribute_set, passthrough=self.parent.attributes)
+			return QuerySetMapper(self.attribute_set.all(), 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'
\ No newline at end of file
+		abstract = True
\ No newline at end of file