dpcollins-google commented on a change in pull request #13470: URL: https://github.com/apache/beam/pull/13470#discussion_r539518416
########## File path: sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/pubsublite/PerPartitionSdf.java ########## @@ -0,0 +1,139 @@ +/* + * 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.sdk.io.gcp.pubsublite; + +import com.google.cloud.pubsublite.Offset; +import com.google.cloud.pubsublite.Partition; +import com.google.cloud.pubsublite.internal.PullSubscriber; +import com.google.cloud.pubsublite.internal.wire.Committer; +import com.google.cloud.pubsublite.proto.SequencedMessage; +import com.google.common.collect.ImmutableList; +import com.google.common.collect.Iterables; +import com.google.common.flogger.GoogleLogger; +import com.google.protobuf.util.Timestamps; +import java.util.Collections; +import java.util.List; +import org.apache.beam.sdk.io.range.OffsetRange; +import org.apache.beam.sdk.transforms.DoFn; +import org.apache.beam.sdk.transforms.SerializableBiFunction; +import org.apache.beam.sdk.transforms.SerializableFunction; +import org.apache.beam.sdk.transforms.splittabledofn.RestrictionTracker; +import org.apache.beam.sdk.util.Sleeper; +import org.joda.time.Duration; +import org.joda.time.Instant; + +class PerPartitionSdf extends DoFn<Partition, SequencedMessage> { + private static final GoogleLogger logger = GoogleLogger.forEnclosingClass(); + private final Duration maxSleepTime; + private final SerializableBiFunction<Partition, Offset, PullSubscriber<SequencedMessage>> + subscriberFactory; + private final SerializableFunction<Partition, Committer> committerFactory; + private final SerializableSupplier<Sleeper> sleeperSupplier; + private final SerializableFunction<Partition, InitialOffsetReader> offsetReaderFactory; + private final SerializableBiFunction< + Partition, OffsetRange, RestrictionTracker<OffsetRange, OffsetByteProgress>> + trackerFactory; + + Duration sleepTimeRemaining; + + PerPartitionSdf( + Duration maxSleepTime, + SerializableBiFunction<Partition, Offset, PullSubscriber<SequencedMessage>> subscriberFactory, + SerializableFunction<Partition, Committer> committerFactory, + SerializableSupplier<Sleeper> sleeperSupplier, + SerializableFunction<Partition, InitialOffsetReader> offsetReaderFactory, + SerializableBiFunction< + Partition, OffsetRange, RestrictionTracker<OffsetRange, OffsetByteProgress>> + trackerFactory) { + this.maxSleepTime = maxSleepTime; + this.sleepTimeRemaining = maxSleepTime; + this.subscriberFactory = subscriberFactory; + this.committerFactory = committerFactory; + this.sleeperSupplier = sleeperSupplier; + this.offsetReaderFactory = offsetReaderFactory; + this.trackerFactory = trackerFactory; + } + + private List<SequencedMessage> doPoll(PullSubscriber<SequencedMessage> subscriber) + throws Exception { + Sleeper sleeper = sleeperSupplier.get(); + while (sleepTimeRemaining.isLongerThan(Duration.ZERO)) { + List<SequencedMessage> messages = subscriber.pull(); + if (!messages.isEmpty()) { + return messages; + } + Duration sleepTime = + Collections.min(ImmutableList.of(sleepTimeRemaining, Duration.millis(50))); + sleepTimeRemaining = sleepTimeRemaining.minus(sleepTime); + sleeper.sleep(sleepTime.getMillis()); + } + return ImmutableList.of(); + } + + @ProcessElement + public ProcessContinuation processElement( + RestrictionTracker<OffsetRange, OffsetByteProgress> tracker, + @Element Partition partition, + OutputReceiver<SequencedMessage> receiver) + throws Exception { + logger.atInfo().log("Starting processing for partition " + partition); + sleepTimeRemaining = maxSleepTime; + Committer committer = committerFactory.apply(partition); + committer.startAsync().awaitRunning(); + try (PullSubscriber<SequencedMessage> subscriber = + subscriberFactory.apply(partition, Offset.of(tracker.currentRestriction().getFrom()))) { + while (true) { + List<SequencedMessage> messages = doPoll(subscriber); + // We polled for as long as possible, yield to the runtime to allow it to reschedule us on + // a new task. + if (messages.isEmpty()) { + logger.atInfo().log("Yielding due to timeout on partition " + partition); + return ProcessContinuation.resume(); + } + Offset lastOffset = Offset.of(Iterables.getLast(messages).getCursor().getOffset()); + long byteSize = messages.stream().mapToLong(SequencedMessage::getSizeBytes).sum(); + if (tracker.tryClaim(OffsetByteProgress.of(lastOffset, byteSize))) { + messages.forEach( + message -> + receiver.outputWithTimestamp( + message, new Instant(Timestamps.toMillis(message.getPublishTime())))); + committer.commitOffset(Offset.of(lastOffset.value() + 1)).get(); Review comment: This does actually affect where the I/O will start on clean restarts. Where this should be depends on how the beam model / dataflow handles drains for SDF pipelines. Do you have any information on this? ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected]
