[Sqlalchemy-tickets] [sqlalchemy] #2670: declared_attr with abstractconcretebase

[sqlalchemy <mi...@zz...>]

#2670: declared_attr with abstractconcretebase
-------------------------+------------------------------------
 Reporter:  zzzeek       |           Owner:  chrisw
     Type:  defect       |          Status:  new
 Priority:  high         |       Milestone:  0.8.xx
Component:  declarative  |        Severity:  major - 1-3 hours
 Keywords:               |  Progress State:  in queue
-------------------------+------------------------------------
 because it's not mapped up front @declared_attr isn't evaluated as
 expected.  might need the plugin to run them again.

 {{{
 #!python
 from sqlalchemy import *
 from sqlalchemy.orm import *
 from sqlalchemy.ext.declarative import (declarative_base, declared_attr,
     AbstractConcreteBase)

 engine = create_engine('sqlite://', echo=True)
 Base = declarative_base()

 class Something(Base):
     __tablename__ = u'something'
     id = Column(Integer, primary_key=True)


 class AbstractConcreteAbstraction(AbstractConcreteBase, Base):
     id = Column(Integer, primary_key=True)
     derpa = Column(Integer)
     derp = Column(Integer)

     @declared_attr
     def something_id(cls):
         return Column(ForeignKey(Something.id))

     @declared_attr
     def something(cls):
         return relationship(Something)


 class ConcreteConcreteAbstraction(AbstractConcreteAbstraction):
     __tablename__ = u'cca'
     __mapper_args__ = {'polymorphic_identity': 'ccb',
         'concrete': True}


 Base.metadata.create_all(engine)

 session = Session(engine)
 print session.query(ConcreteConcreteAbstraction).filter(
         ConcreteConcreteAbstraction.something.has(id=1)).all()

 # workaround needed
 # AbstractConcreteAbstraction.something = relationship(Something)

 print session.query(AbstractConcreteAbstraction).filter(
         AbstractConcreteAbstraction.something.has(id=1)).all()

 }}}

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Ticket URL: <http://www.sqlalchemy.org/trac/ticket/2670>
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