text: # Copyright 2018 gRPC authors.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  """Tests server context abort mechanism"""
  
  import unittest
  import collections
  import gc
  import logging
  import weakref
  
  import grpc
  
  from tests.unit import test_common
  from tests.unit.framework.common import test_constants
  
  _ABORT = '/test/abort'
  _ABORT_WITH_STATUS = '/test/AbortWithStatus'
  _INVALID_CODE = '/test/InvalidCode'
  
  _REQUEST = b'\x00\x00\x00'
  _RESPONSE = b'\x00\x00\x00'
  
  _ABORT_DETAILS = 'Abandon ship!'
  _ABORT_METADATA = (('a-trailing-metadata', '42'),)
  
  
  class _Status(
          collections.namedtuple('_Status',
                                 ('code', 'details', 'trailing_metadata')),
          grpc.Status):
      pass
  
  
  class _Object(object):
      pass
  
  
  do_not_leak_me = _Object()
  
  
  def abort_unary_unary(request, servicer_context):
      this_should_not_be_leaked = do_not_leak_me
      servicer_context.abort(
          grpc.StatusCode.INTERNAL,
          _ABORT_DETAILS,
      )
      raise Exception('This line should not be executed!')
  
  
  def abort_with_status_unary_unary(request, servicer_context):
      servicer_context.abort_with_status(
          _Status(
              code=grpc.StatusCode.INTERNAL,
              details=_ABORT_DETAILS,
              trailing_metadata=_ABORT_METADATA,
          ))
      raise Exception('This line should not be executed!')
  
  
  def invalid_code_unary_unary(request, servicer_context):
      servicer_context.abort(
          42,
          _ABORT_DETAILS,
      )
  
  
  class _GenericHandler(grpc.GenericRpcHandler):
  
      def service(self, handler_call_details):
          if handler_call_details.method == _ABORT:
              return grpc.unary_unary_rpc_method_handler(abort_unary_unary)
          elif handler_call_details.method == _ABORT_WITH_STATUS:
              return grpc.unary_unary_rpc_method_handler(
                  abort_with_status_unary_unary)
          elif handler_call_details.method == _INVALID_CODE:
              return grpc.stream_stream_rpc_method_handler(
                  invalid_code_unary_unary)
          else:
              return None
  
  
  class AbortTest(unittest.TestCase):
  
      def setUp(self):
          self._server = test_common.test_server()
          port = self._server.add_insecure_port('[::]:0')
          self._server.add_generic_rpc_handlers((_GenericHandler(),))
          self._server.start()
  
          self._channel = grpc.insecure_channel('localhost:%d' % port)
  
      def tearDown(self):
          self._channel.close()
          self._server.stop(0)
  
      def test_abort(self):
          with self.assertRaises(grpc.RpcError) as exception_context:
              self._channel.unary_unary(_ABORT)(_REQUEST)
          rpc_error = exception_context.exception
  
          self.assertEqual(rpc_error.code(), grpc.StatusCode.INTERNAL)
          self.assertEqual(rpc_error.details(), _ABORT_DETAILS)
  
      # This test ensures that abort() does not store the raised exception, which
      # on Python 3 (via the `__traceback__` attribute) holds a reference to
      # all local vars. Storing the raised exception can prevent GC and stop the
      # grpc_call from being unref'ed, even after server shutdown.
      @unittest.skip("https://github.com/grpc/grpc/issues/17927")
      def test_abort_does_not_leak_local_vars(self):
          global do_not_leak_me  # pylint: disable=global-statement
          weak_ref = weakref.ref(do_not_leak_me)
  
          # Servicer will abort() after creating a local ref to do_not_leak_me.
          with self.assertRaises(grpc.RpcError):
              self._channel.unary_unary(_ABORT)(_REQUEST)
  
          # Server may still have a stack frame reference to the exception even
          # after client sees error, so ensure server has shutdown.
          self._server.stop(None)
          do_not_leak_me = None
          self.assertIsNone(weak_ref())
  
      def test_abort_with_status(self):
          with self.assertRaises(grpc.RpcError) as exception_context:
              self._channel.unary_unary(_ABORT_WITH_STATUS)(_REQUEST)
          rpc_error = exception_context.exception
  
          self.assertEqual(rpc_error.code(), grpc.StatusCode.INTERNAL)
          self.assertEqual(rpc_error.details(), _ABORT_DETAILS)
          self.assertEqual(rpc_error.trailing_metadata(), _ABORT_METADATA)
  
      def test_invalid_code(self):
          with self.assertRaises(grpc.RpcError) as exception_context:
              self._channel.unary_unary(_INVALID_CODE)(_REQUEST)
          rpc_error = exception_context.exception
  
          self.assertEqual(rpc_error.code(), grpc.StatusCode.UNKNOWN)
          self.assertEqual(rpc_error.details(), _ABORT_DETAILS)
  
  
  if __name__ == '__main__':
      logging.basicConfig()
      unittest.main(verbosity=2)
  