X-Git-Url: http://git.ithinksw.org/philo.git/blobdiff_plain/2f90757a89424650440d684e08cbf53d98cec8fd..bf78e0c846297a4f732ffdfc181b3c89428fd2a4:/models/base.py?ds=sidebyside diff --git a/models/base.py b/models/base.py index ae15d16..af1e880 100644 --- a/models/base.py +++ b/models/base.py @@ -2,14 +2,17 @@ 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 force_unicode 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): @@ -21,6 +24,7 @@ class Tag(models.Model): class Meta: app_label = 'philo' + ordering = ('name',) class Titled(models.Model): @@ -41,6 +45,9 @@ def register_value_model(model): value_content_type_limiter.register_class(model) +register_value_model(Tag) + + def unregister_value_model(model): value_content_type_limiter.unregister_class(model) @@ -48,14 +55,15 @@ def unregister_value_model(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 set_value(self, value): + raise NotImplementedError - def apply_data(self, data): + def value_formfields(self, **kwargs): + """Define any formfields that would be used to construct an instance of this value.""" raise NotImplementedError - def value_formfield(self, **kwargs): + def construct_instance(self, **kwargs): + """Apply cleaned data from the formfields generated by valid_formfields to oneself.""" raise NotImplementedError def __unicode__(self): @@ -69,17 +77,22 @@ attribute_value_limiter = ContentTypeSubclassLimiter(AttributeValue) class JSONValue(AttributeValue): - value = JSONField() #verbose_name='Value (JSON)', help_text='This value must be valid JSON.') + value = JSONField(verbose_name='Value (JSON)', help_text='This value must be valid JSON.', default='null', db_index=True) def __unicode__(self): - return self.value_json + return force_unicode(self.value) - def value_formfield(self, **kwargs): - kwargs['initial'] = self.value_json - return self._meta.get_field('value').formfield(**kwargs) + def value_formfields(self): + kwargs = {'initial': self.value_json} + field = self._meta.get_field('value') + return {field.name: field.formfield(**kwargs)} - def apply_data(self, cleaned_data): - self.value = cleaned_data.get('value', None) + def construct_instance(self, **kwargs): + field_name = self._meta.get_field('value').name + self.set_value(kwargs.pop(field_name, None)) + + def set_value(self, value): + self.value = value class Meta: app_label = 'philo' @@ -87,22 +100,36 @@ class JSONValue(AttributeValue): 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) + object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True, db_index=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. + def value_formfields(self): + field = self._meta.get_field('content_type') + fields = {field.name: field.formfield(initial=getattr(self.content_type, 'pk', None))} + + if self.content_type: + kwargs = { + 'initial': self.object_id, + 'required': False, + 'queryset': self.content_type.model_class()._default_manager.all() + } + fields['value'] = forms.ModelChoiceField(**kwargs) + return fields + + def construct_instance(self, **kwargs): + field_name = self._meta.get_field('content_type').name + ct = kwargs.pop(field_name, None) + if ct is None or ct != self.content_type: self.object_id = None + self.content_type = ct + else: + value = kwargs.pop('value', None) + self.set_value(value) + if value is None: + self.content_type = ct + + def set_value(self, value): + self.value = value class Meta: app_label = 'philo' @@ -112,57 +139,76 @@ 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 get_object_ids(self): + return self.values.values_list('object_id', flat=True) + object_ids = property(get_object_ids) def set_value(self, value): - # Value is probably a queryset - but allow any iterable. + # Value must be a queryset. Watch out for ModelMultipleChoiceField; + # it returns its value as a list if empty. - # 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 = [] + self.content_type = ContentType.objects.get_for_model(value.model) # 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() + object_ids = value.values_list('id', flat=True) - 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) + # These lines shouldn't be necessary; however, if object_ids is an EmptyQuerySet, + # the code (specifically the object_id__in query) won't work without them. Unclear why... + # TODO: is this still the case? + if not object_ids: + self.values.all().delete() + else: + self.values.exclude(object_id__in=object_ids, content_type=self.content_type).delete() + + current_ids = self.object_ids + + for object_id in object_ids: + if object_id in current_ids: + continue + self.values.create(content_type=self.content_type, object_id=object_id) - def value_formfield(self, form_class=forms.ModelMultipleChoiceField, **kwargs): + def get_value(self): 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) + + # HACK to be safely explicit until http://code.djangoproject.com/ticket/15145 is resolved + object_ids = self.object_ids + manager = self.content_type.model_class()._default_manager + if not object_ids: + return manager.none() + return manager.filter(id__in=self.object_ids) - def apply_data(self, cleaned_data): - if 'value' in cleaned_data and cleaned_data['value'] is not None: - self.value = cleaned_data['value'] + value = property(get_value, set_value) + + def value_formfields(self): + field = self._meta.get_field('content_type') + fields = {field.name: field.formfield(initial=getattr(self.content_type, 'pk', None))} + + if self.content_type: + kwargs = { + 'initial': self.object_ids, + 'required': False, + 'queryset': self.content_type.model_class()._default_manager.all() + } + fields['value'] = forms.ModelMultipleChoiceField(**kwargs) + return fields + + def construct_instance(self, **kwargs): + field_name = self._meta.get_field('content_type').name + ct = kwargs.pop(field_name, None) + if ct is None or ct != self.content_type: + self.values.clear() + self.content_type = ct 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 = [] + value = kwargs.get('value', None) + if not value: + value = self.content_type.model_class()._default_manager.none() + self.set_value(value) + construct_instance.alters_data = True class Meta: app_label = 'philo' @@ -170,14 +216,14 @@ class ManyToManyValue(AttributeValue): 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_object_id = models.PositiveIntegerField(verbose_name='Entity ID', db_index=True) entity = generic.GenericForeignKey('entity_content_type', 'entity_object_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_object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True, db_index=True) value = generic.GenericForeignKey('value_content_type', 'value_object_id') - key = models.CharField(max_length=255) + key = models.CharField(max_length=255, validators=[RegexValidator("\w+")], help_text="Must contain one or more alphanumeric characters or underscores.", db_index=True) def __unicode__(self): return u'"%s": %s' % (self.key, self.value) @@ -225,9 +271,9 @@ class EntityOptions(object): class EntityBase(models.base.ModelBase): def __new__(cls, name, bases, attrs): + entity_meta = attrs.pop('EntityMeta', None) new = super(EntityBase, cls).__new__(cls, name, bases, attrs) - entity_options = attrs.pop('EntityMeta', None) - setattr(new, '_entity_meta', EntityOptions(entity_options)) + new.add_to_class('_entity_meta', EntityOptions(entity_meta)) entity_class_prepared.send(sender=new) return new @@ -241,37 +287,6 @@ class Entity(models.Model): def attributes(self): 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 _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 @@ -279,23 +294,23 @@ class Entity(models.Model): 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='/', field='slug'): """ 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. """ + # 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: @@ -306,11 +321,13 @@ class TreeManager(models.Manager): # 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): + def make_query_kwargs(segments, root): kwargs = {} prefix = "" revsegs = list(segments) @@ -320,72 +337,88 @@ class TreeManager(models.Manager): kwargs["%s%s__exact" % (prefix, field)] = segment prefix += "parent__" - kwargs[prefix[:-2]] = root + 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): + 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[:depth])) + obj = self.get(**make_query_kwargs(segments[deepest_level:depth], deepest_found or root)) except self.model.DoesNotExist: - if absolute_result: - raise + 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 - depth = (deepest_found + depth)/2 - if deepest_found == depth: + 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, pathsep.join(segments) raise - # Try finding one with half the path since the deepest find. return find_obj(segments, depth, deepest_found) else: - # Yay! Found one! Could there be a deeper one? - if absolute_result: - return obj + # 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, pathsep.join(segments[deepest_level:]) or None - deepest_found = depth - depth = (len(segments) + depth)/2 + depth += (len(segments) - depth)/2 or len(segments) - depth - if deepest_found == depth: - return obj, build_path(segments[deepest_found:]) or None + if depth > deepest_level + obj.get_descendant_count(): + depth = deepest_level + obj.get_descendant_count() + + if deepest_level == depth: + return obj, pathsep.join(segments[deepest_level:]) or None try: - return find_obj(segments, depth, deepest_found) + return find_obj(segments, depth, obj) except self.model.DoesNotExist: - # Then the deepest one was already found. - return obj, build_path(segments[deepest_found:]) + # Then this was the deepest. + return obj, pathsep.join(segments[deepest_level:]) + + if absolute_result: + return self.get(**make_query_kwargs(segments, root)) - return find_obj(segments, len(segments), 0) + # 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(max_length=255) - def has_ancestor(self, ancestor): - parent = self - while parent: - if parent == ancestor: - return True - parent = parent.parent - return False - def get_path(self, root=None, pathsep='/', field='slug'): - if root is not None and not self.has_ancestor(root): + if root == self: + return '' + + if root is not None and not self.is_descendant_of(root): raise AncestorDoesNotExist(root) - path = getattr(self, field, '?') - parent = self.parent - while parent and parent != root: - path = getattr(parent, field, '?') + pathsep + path - parent = parent.parent - return path + qs = self.get_ancestors(include_self=True) + + 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 qs]) path = property(get_path) def __unicode__(self): @@ -396,7 +429,17 @@ class TreeModel(models.Model): abstract = True +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: