如何在App Engine NDB中测试DateTimeProperty？

Question

我正在尝试使用App Engine的NDB测试DateTimeProperty的过滤器,但我将它设置为auto_now？

有没有办法解决这个问题进行单元测试？

例:

class MyModel(ndb.Model)
  timestamp = ndb.DateTimeProperty(auto_now)
  name = ndb.StringProperty()


def testMyModelFilter(self):
  test1 = MyModel()
  test1.timestamp = datetime.datetime.now() - datetime.timedelta(hours=2)
  test1.put()
  test2 = MyModel()
  test2.timestamp = datetime.datetime.now() - datetime.timedelta(hours=1)
  test2.put()

  hour_ago = datetime.datetime.now() - datetime.timedelta(hours=1)
  fetched = MyModel.query().filter(MyModel.timestamp < hour_ago).fetch(
      None, keys_only=True)

不幸的是,当我使用test.put()将其提交到数据存储区时,它会使用put()时的时间.

Answer 1

因此,您可以尝试的一件事(正如@mjibson所暗示的那样)在测试期间覆盖您的模型.由于MyModel它本身是一个对象,因此您可以将测试的_auto_now属性修改timestamp为False.例如:

def testMyModelFilter(self):
  # Change the auto_now parameter to False
  MyModel.timestamp._auto_now = False

  # Test as usual...
  test1 = MyModel()
  test1.timestamp = datetime.datetime.now() - datetime.timedelta(hours=2)
  test1.put()
  test2 = MyModel()
  test2.timestamp = datetime.datetime.now() - datetime.timedelta(hours=1)
  test2.put()

  hour_ago = datetime.datetime.now() - datetime.timedelta(hours=1)
  fetched = MyModel.query().filter(MyModel.timestamp < hour_ago).fetch(
      None, keys_only=True)

我记得在其他地方看过这种技术,所以如果我能找到它我会链接(如果它可以工作,当然:)).