#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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.
#
# pytype: skip-file
from concurrent.futures import ThreadPoolExecutor
import grpc
from apache_beam.portability.api import beam_runner_api_pb2_grpc
[docs]
class TestStreamServiceController(
beam_runner_api_pb2_grpc.TestStreamServiceServicer):
"""A server that streams TestStreamPayload.Events from a single EventRequest.
This server is used as a way for TestStreams to receive events from file.
"""
def __init__(self, reader, endpoint=None, exception_handler=None):
self._server = grpc.server(ThreadPoolExecutor(max_workers=10))
self._server_started = False
self._server_stopped = False
if endpoint:
self.endpoint = endpoint
self._server.add_insecure_port(self.endpoint)
else:
port = self._server.add_insecure_port('localhost:0')
self.endpoint = 'localhost:{}'.format(port)
beam_runner_api_pb2_grpc.add_TestStreamServiceServicer_to_server(
self, self._server)
self._reader = reader
self._exception_handler = exception_handler
if not self._exception_handler:
self._exception_handler = lambda _: False
[docs]
def start(self):
# A server can only be started if never started and never stopped before.
if self._server_started or self._server_stopped:
return
self._server_started = True
self._server.start()
[docs]
def stop(self):
# A server can only be stopped if already started and never stopped before.
if not self._server_started or self._server_stopped:
return
self._server_started = False
self._server_stopped = True
self._server.stop(0)
# This was introduced in grpcio 1.24 and might be gone in the future. Keep
# this check in case the runtime is on a older, current or future grpcio.
if hasattr(self._server, 'wait_for_termination'):
self._server.wait_for_termination()
[docs]
def Events(self, request, context):
"""Streams back all of the events from the streaming cache."""
# TODO(srohde): Once we get rid of the CacheManager, get rid of this 'full'
# label.
tags = [None if tag == 'None' else tag for tag in request.output_ids]
try:
reader = self._reader.read_multiple([('full', tag) for tag in tags])
while True:
e = next(reader)
yield e
except StopIteration:
pass
except Exception as e:
if not self._exception_handler(e):
raise e