I was trying to add an AttributeExtension to a property from my MapperExtension but I get this error when trying to access the property:
AttributeError: 'Mapper' object has no attribute '_props' Here's a test case: from sqlalchemy import create_engine, Column from sqlalchemy.ext.declarative import declarative_base from sqlalchemy.types import Integer, String from sqlalchemy.orm import scoped_session, sessionmaker, deferred from sqlalchemy.orm.interfaces import MapperExtension engine = create_engine('sqlite:///:memory:', echo=True) Base = declarative_base(bind=engine) class MyExtension(MapperExtension): def __init__(self, property): self.property = property def instrument_class(self, mapper, class_): property = mapper.get_property(self.property) print property class Item(Base): __tablename__ = 'items' __mapper_args__ = {'extension': MyExtension('name')} id = Column(Integer, primary_key=True) name = deferred(Column(String)) -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalch...@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.