m-trieu commented on code in PR #32774: URL: https://github.com/apache/beam/pull/32774#discussion_r1805822704
########## runners/google-cloud-dataflow-java/worker/src/main/java/org/apache/beam/runners/dataflow/worker/streaming/harness/GlobalDataStreamSender.java: ########## @@ -0,0 +1,65 @@ +/* + * 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. + */ +package org.apache.beam.runners.dataflow.worker.streaming.harness; + +import java.io.Closeable; +import java.util.function.Supplier; +import javax.annotation.concurrent.ThreadSafe; +import org.apache.beam.runners.dataflow.worker.windmill.WindmillEndpoints.Endpoint; +import org.apache.beam.runners.dataflow.worker.windmill.client.WindmillStream.GetDataStream; +import org.apache.beam.sdk.annotations.Internal; + +@Internal +@ThreadSafe +final class GlobalDataStreamSender implements Closeable, Supplier<GetDataStream> { + private final Endpoint endpoint; + private final GetDataStream delegate; + private volatile boolean started; + + GlobalDataStreamSender(GetDataStream delegate, Endpoint endpoint) { + this.delegate = delegate; + this.started = false; + this.endpoint = endpoint; + } + + @Override + public GetDataStream get() { + if (!started) { + startStream(); + } + + return delegate; + } + + private synchronized void startStream() { + // Check started again after we acquire the lock. + if (!started) { + started = true; + delegate.start(); + } + } + + @Override + public void close() { + delegate.shutdown(); Review Comment: it is safe to shutdown here. calling start a shutdown stream will do nothing and shutting down a stream before starting it is a valid state (i.e we never fetch side input data, but when we attempt to close the streams we remove any streams that are in `StreamingBackends.globalDataStreams`) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
