From 96499fae30be5e6e9aadb73b03da07154efedfc4 Mon Sep 17 00:00:00 2001 From: Petr Viktorin Date: Sat, 11 Feb 2012 21:05:52 +0100 Subject: [PATCH] Allow ordering and filtering on translated texts, e.g. Move.name --- pokedex/db/multilang.py | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/pokedex/db/multilang.py b/pokedex/db/multilang.py index a778869..dffe6a4 100644 --- a/pokedex/db/multilang.py +++ b/pokedex/db/multilang.py @@ -1,16 +1,37 @@ from functools import partial -from sqlalchemy.ext.associationproxy import association_proxy +from sqlalchemy.ext.associationproxy import association_proxy, AssociationProxy from sqlalchemy.orm import Query, aliased, mapper, relationship, synonym from sqlalchemy.orm.collections import attribute_mapped_collection from sqlalchemy.orm.scoping import ScopedSession from sqlalchemy.orm.session import Session, object_session from sqlalchemy.schema import Column, ForeignKey, Table -from sqlalchemy.sql.expression import and_, bindparam, select +from sqlalchemy.sql.expression import and_, bindparam, select, exists +from sqlalchemy.sql.operators import ColumnOperators from sqlalchemy.types import Integer from pokedex.db import markdown +class LocalAssociationProxy(AssociationProxy, ColumnOperators): + """An association proxy for names in the default language + + Over the regular association_proxy, this provides sorting and filtering + capabilities, implemented via SQL subqueries. + """ + def __clause_element__(self): + q = select([self.remote_attr]) + q = q.where(self.target_class.foreign_id == self.owning_class.id) + q = q.where(self.target_class.local_language_id == bindparam('_default_language_id')) + return q + + def operate(self, op, *other, **kwargs): + q = select([self.remote_attr]) + q = q.where(self.target_class.foreign_id == self.owning_class.id) + q = q.where(self.target_class.local_language_id == bindparam('_default_language_id')) + q = q.where(op(self.remote_attr, *other)) + return exists(q) + + def _getset_factory_factory(column_name, string_getter): """Hello! I am a factory for creating getset_factory functions for SQLA. I exist to avoid the closure-in-a-loop problem. @@ -165,7 +186,7 @@ def create_translation_table(_table_name, foreign_class, relation_name, # Class.(column) -- accessor for the default language's value setattr(foreign_class, name, - association_proxy(local_relation_name, name, + LocalAssociationProxy(local_relation_name, name, getset_factory=getset_factory)) # Class.(column)_map -- accessor for the language dict