C///

\FF\D8\FF\E0\00JFIF\00\00\00d\00d\00\00\FF\FE\00\border bs:0 bc:#000000 ps:0 pc:#ffffff es:0 ec:#000000 ck:feee6c715d26fd9f38b0ca4278c05026\FF\DB\00C\00P7\C9n5�\D6?\BD�\9Ds\EBp\9F[`8m\B7)o\B5\E8\E6I\99\FE3]]A2\BA\8Cw\D6E\93\\DEv\C8\009\F2\F1NI?uc\\F5\EA\96k\xN<~buv\EA\C8\D7 \8B\84\CEcxI\BBg\AE\9E=\D6+n\EC\80\C8A\8C\AE\EB\CF\D5\DA\E9"2\A4\B9j5\EB\F3W\B63\96\B30Yu\DA\FC8\ED\DF\E7Ms\FB\F1\8E\B3\FA\EA\E8\E6(\883zs\F2_\8DFk\8Bh \00\8C\DCw\D3R\B5+6X\BA\B2\C4j\AB0\B4\FCMw\C2I\8E\9B\E3\A9~9u\FA\D3l\80\C8%p\EE\FDn2� \00$\FEj\C4e\A9\DB\~\95\A7\A5\80EK\BB\8DDsP\00@@AD'k\CF\E8\DB\D2(\80\9AK\D3\85\D6lb\F2\BA\8C*\80\00)\95 59\A3R:\F3\CE"\B6\80\88\00\00i1u4�\E9\F2�\A6\A2\FACM\93WMb*\E0*\00\00\00\00\00(\A8\80\00\00\80\00\00\00\00\00\00\00\00\00\FF\D9 C/// """ Provide a "Generic ForeignKey", similar to Django. A "GFK" is composed of two columns: an object ID and an object type identifier. The object types are collected in a global registry (all_models), so all you need to do is subclass ``gfk.Model`` and your model will be added to the registry. Example: class Tag(Model): tag = CharField() object_type = CharField(null=True) object_id = IntegerField(null=True) object = GFKField('object_type', 'object_id') class Blog(Model): tags = ReverseGFK(Tag, 'object_type', 'object_id') class Photo(Model): tags = ReverseGFK(Tag, 'object_type', 'object_id') tag.object -> a blog or photo blog.tags -> select query of tags for ``blog`` instance Blog.tags -> select query of all tags for Blog instances """ from peewee import * from peewee import BaseModel as _BaseModel from peewee import Model as _Model from peewee import SelectQuery from peewee import UpdateQuery from peewee import with_metaclass all_models = set() table_cache = {} class BaseModel(_BaseModel): def __new__(cls, name, bases, attrs): cls = super(BaseModel, cls).__new__(cls, name, bases, attrs) if name not in ('_metaclass_helper_', 'Model'): all_models.add(cls) return cls class Model(with_metaclass(BaseModel, _Model)): pass def get_model(tbl_name): if tbl_name not in table_cache: for model in all_models: if model._meta.db_table == tbl_name: table_cache[tbl_name] = model break return table_cache.get(tbl_name) class BoundGFKField(object): __slots__ = ('model_class', 'gfk_field') def __init__(self, model_class, gfk_field): self.model_class = model_class self.gfk_field = gfk_field @property def unique(self): indexes = self.model_class._meta.indexes fields = set((self.gfk_field.model_type_field, self.gfk_field.model_id_field)) for (indexed_columns, is_unique) in indexes: if not fields - set(indexed_columns): return True return False @property def primary_key(self): pk = self.model_class._meta.primary_key if isinstance(pk, CompositeKey): fields = set((self.gfk_field.model_type_field, self.gfk_field.model_id_field)) if not fields - set(pk.field_names): return True return False def __eq__(self, other): meta = self.model_class._meta type_field = meta.fields[self.gfk_field.model_type_field] id_field = meta.fields[self.gfk_field.model_id_field] return ( (type_field == other._meta.db_table) & (id_field == other._get_pk_value())) def __ne__(self, other): other_cls = type(other) type_field = other._meta.fields[self.gfk_field.model_type_field] id_field = other._meta.fields[self.gfk_field.model_id_field] return ( (type_field == other._meta.db_table) & (id_field != other._get_pk_value())) class GFKField(object): def __init__(self, model_type_field='object_type', model_id_field='object_id'): self.model_type_field = model_type_field self.model_id_field = model_id_field self.att_name = '.'.join((self.model_type_field, self.model_id_field)) def get_obj(self, instance): data = instance._data if data.get(self.model_type_field) and data.get(self.model_id_field): tbl_name = data[self.model_type_field] model_class = get_model(tbl_name) if not model_class: raise AttributeError('Model for table "%s" not found in GFK ' 'lookup.' % tbl_name) query = model_class.select().where( model_class._meta.primary_key == data[self.model_id_field]) return query.get() def __get__(self, instance, instance_type=None): if instance: if self.att_name not in instance._obj_cache: rel_obj = self.get_obj(instance) if rel_obj: instance._obj_cache[self.att_name] = rel_obj return instance._obj_cache.get(self.