Deleting all entities in a namespace on Google App Engine with Python.

gistfile1.py

DEV = os.environ['SERVER_SOFTWARE'].startswith('Dev')
APP_ID = os.environ['APPLICATION_ID']
def deleteDBandMemcache():

  if not DEV and APP_ID.find('test') == -1:
    # We're not in Kansas anymore. i.e. This is PRODUCTION.
    # To test in the cloud, the app id must contain 'test'.
    logging.error('trying to run tests on production server = no beuno')
    return

  """Delete all entities in a namespace."""
  from google.appengine.api import namespace_manager
  ######################################
  """ #######  IMPORTANT ########## """
  TESTSPACE = 'test'
  namespace_manager.set_namespace(TESTSPACE)
  """ #####  DO NOT DELETE ######## """
  ######################################

  if namespace_manager.get_namespace() != 'test':
    logging.error('Tyring to delete from namespace other than test = muy mal')
    return

  # Clear datastore entities
  for model in list(get_all_models()):
    ndb.delete_multi(model.query().fetch(999999, keys_only=True))

  # Clear memcache
  ndb.get_context().clear_cache()
  
def get_all_models():
    import sys
    import inspect
    for name, obj in inspect.getmembers(sys.modules[__name__]):
        if inspect.isclass(obj):
            yield obj