/*
* 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.flink.translation.wrappers.streaming;
import static com.google.common.base.Preconditions.checkState;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import org.apache.beam.runners.core.KeyedWorkItem;
import org.apache.beam.runners.core.KeyedWorkItems;
import org.apache.beam.runners.core.OutputAndTimeBoundedSplittableProcessElementInvoker;
import org.apache.beam.runners.core.OutputWindowedValue;
import org.apache.beam.runners.core.SplittableParDoViaKeyedWorkItems.ProcessFn;
import org.apache.beam.runners.core.StateInternals;
import org.apache.beam.runners.core.StateInternalsFactory;
import org.apache.beam.runners.core.TimerInternals;
import org.apache.beam.runners.core.TimerInternalsFactory;
import org.apache.beam.runners.core.construction.ElementAndRestriction;
import org.apache.beam.sdk.coders.Coder;
import org.apache.beam.sdk.options.PipelineOptions;
import org.apache.beam.sdk.transforms.DoFn;
import org.apache.beam.sdk.transforms.splittabledofn.RestrictionTracker;
import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
import org.apache.beam.sdk.transforms.windowing.PaneInfo;
import org.apache.beam.sdk.util.WindowedValue;
import org.apache.beam.sdk.values.PCollectionView;
import org.apache.beam.sdk.values.TupleTag;
import org.apache.beam.sdk.values.WindowingStrategy;
import org.apache.flink.streaming.api.operators.InternalTimer;
import org.joda.time.Duration;
import org.joda.time.Instant;
/**
* Flink operator for executing splittable {@link DoFn DoFns}. Specifically, for executing
* the {@code @ProcessElement} method of a splittable {@link DoFn}.
*/
public class SplittableDoFnOperator<
InputT, FnOutputT, OutputT, RestrictionT, TrackerT extends RestrictionTracker<RestrictionT>>
extends DoFnOperator<
KeyedWorkItem<String, ElementAndRestriction<InputT, RestrictionT>>, FnOutputT, OutputT> {
private transient ScheduledExecutorService executorService;
public SplittableDoFnOperator(
DoFn<KeyedWorkItem<String, ElementAndRestriction<InputT, RestrictionT>>, FnOutputT> doFn,
String stepName,
Coder<
WindowedValue<
KeyedWorkItem<String, ElementAndRestriction<InputT, RestrictionT>>>> inputCoder,
TupleTag<FnOutputT> mainOutputTag,
List<TupleTag<?>> additionalOutputTags,
OutputManagerFactory<OutputT> outputManagerFactory,
WindowingStrategy<?, ?> windowingStrategy,
Map<Integer, PCollectionView<?>> sideInputTagMapping,
Collection<PCollectionView<?>> sideInputs,
PipelineOptions options,
Coder<?> keyCoder) {
super(
doFn,
stepName,
inputCoder,
mainOutputTag,
additionalOutputTags,
outputManagerFactory,
windowingStrategy,
sideInputTagMapping,
sideInputs,
options,
keyCoder);
}
@Override
public void open() throws Exception {
super.open();
checkState(doFn instanceof ProcessFn);
StateInternalsFactory<String> stateInternalsFactory = new StateInternalsFactory<String>() {
@Override
public StateInternals stateInternalsForKey(String key) {
//this will implicitly be keyed by the key of the incoming
// element or by the key of a firing timer
return (StateInternals) stateInternals;
}
};
TimerInternalsFactory<String> timerInternalsFactory = new TimerInternalsFactory<String>() {
@Override
public TimerInternals timerInternalsForKey(String key) {
//this will implicitly be keyed like the StateInternalsFactory
return timerInternals;
}
};
executorService = Executors.newSingleThreadScheduledExecutor(Executors.defaultThreadFactory());
((ProcessFn) doFn).setStateInternalsFactory(stateInternalsFactory);
((ProcessFn) doFn).setTimerInternalsFactory(timerInternalsFactory);
((ProcessFn) doFn).setProcessElementInvoker(
new OutputAndTimeBoundedSplittableProcessElementInvoker<>(
doFn,
serializedOptions.getPipelineOptions(),
new OutputWindowedValue<FnOutputT>() {
@Override
public void outputWindowedValue(
FnOutputT output,
Instant timestamp,
Collection<? extends BoundedWindow> windows,
PaneInfo pane) {
outputManager.output(
mainOutputTag,
WindowedValue.of(output, timestamp, windows, pane));
}
@Override
public <AdditionalOutputT> void outputWindowedValue(
TupleTag<AdditionalOutputT> tag,
AdditionalOutputT output,
Instant timestamp,
Collection<? extends BoundedWindow> windows,
PaneInfo pane) {
outputManager.output(tag, WindowedValue.of(output, timestamp, windows, pane));
}
},
sideInputReader,
executorService,
10000,
Duration.standardSeconds(10)));
}
@Override
public void fireTimer(InternalTimer<?, TimerInternals.TimerData> timer) {
doFnRunner.processElement(WindowedValue.valueInGlobalWindow(
KeyedWorkItems.<String, ElementAndRestriction<InputT, RestrictionT>>timersWorkItem(
(String) stateInternals.getKey(),
Collections.singletonList(timer.getNamespace()))));
}
@Override
public void close() throws Exception {
super.close();
executorService.shutdown();
long shutdownTimeout = Duration.standardSeconds(10).getMillis();
try {
if (!executorService.awaitTermination(shutdownTimeout, TimeUnit.MILLISECONDS)) {
LOG.debug("The scheduled executor service did not properly terminate. Shutting "
+ "it down now.");
executorService.shutdownNow();
}
} catch (InterruptedException e) {
LOG.debug("Could not properly await the termination of the scheduled executor service.", e);
executorService.shutdownNow();
}
}
}