Question

在Google App Engine上使用Python时，克隆（复制）Expando类对象的好方法是什么？

我在这里遇到了一些代码，但除非我弄错了，否则它在expando属性上不起作用：Copy an entity in Google App Engine datastore in Python without knowing property names at 'compile' time

谢谢！

Answer 1

以下是Nick's function的修订版，其中包含动态属性：

def clone_entity(e, **extra_args):
  """Clones an entity, adding or overriding constructor attributes.

  The cloned entity will have exactly the same property values as the original
  entity, except where overridden. By default it will have no parent entity or
  key name, unless supplied.

  Args:
    e: The entity to clone
    extra_args: Keyword arguments to override from the cloned entity and pass
      to the constructor.
  Returns:
    A cloned, possibly modified, copy of entity e.
  """
  klass = e.__class__
  props = dict((k, v.__get__(e, klass)) for k, v in klass.properties().iteritems())
  props.update(dict([(k, getattr(e, k)) for k in e.dynamic_properties()]))
  props.update(extra_args)
  return klass(**props)

用于App Engine的Python中的Clone和Expando类对象

1 个答案: