Classe « registry »

Méthode sqlalchemy.orm.registry.generate_base

Signature de la méthode generate_base

def generate_base(self, mapper=None, cls=<class 'object'>, name='Base', metaclass=<class 'sqlalchemy.orm.decl_api.DeclarativeMeta'>) 

Description

generate_base.__doc__

Generate a declarative base class.

        Classes that inherit from the returned class object will be
        automatically mapped using declarative mapping.

        E.g.::

            from sqlalchemy.orm import registry

            mapper_registry = registry()

            Base = mapper_registry.generate_base()

            class MyClass(Base):
                __tablename__ = "my_table"
                id = Column(Integer, primary_key=True)

        The above dynamically generated class is equivalent to the
        non-dynamic example below::

            from sqlalchemy.orm import registry
            from sqlalchemy.orm.decl_api import DeclarativeMeta

            mapper_registry = registry()

            class Base(metaclass=DeclarativeMeta):
                __abstract__ = True
                registry = mapper_registry
                metadata = mapper_registry.metadata

                __init__ = mapper_registry.constructor

        The :meth:`_orm.registry.generate_base` method provides the
        implementation for the :func:`_orm.declarative_base` function, which
        creates the :class:`_orm.registry` and base class all at once.

        See the section :ref:`orm_declarative_mapping` for background and
        examples.

        :param mapper:
          An optional callable, defaults to :func:`~sqlalchemy.orm.mapper`.
          This function is used to generate new :class:`_orm.Mapper` objects.

        :param cls:
          Defaults to :class:`object`. A type to use as the base for the
          generated declarative base class. May be a class or tuple of classes.

        :param name:
          Defaults to ``Base``.  The display name for the generated
          class.  Customizing this is not required, but can improve clarity in
          tracebacks and debugging.

        :param metaclass:
          Defaults to :class:`.DeclarativeMeta`.  A metaclass or __metaclass__
          compatible callable to use as the meta type of the generated
          declarative base class.

        .. seealso::

            :ref:`orm_declarative_mapping`

            :func:`_orm.declarative_base`