content: /*
   * 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.core;
  
  import java.util.Collection;
  import java.util.List;
  import java.util.Map;
  import org.apache.beam.runners.core.SplittableParDoViaKeyedWorkItems.ProcessFn;
  import org.apache.beam.runners.core.StatefulDoFnRunner.CleanupTimer;
  import org.apache.beam.runners.core.StatefulDoFnRunner.StateCleaner;
  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.DoFnSchemaInformation;
  import org.apache.beam.sdk.transforms.reflect.DoFnSignatures;
  import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
  import org.apache.beam.sdk.util.WindowedValueMultiReceiver;
  import org.apache.beam.sdk.values.KV;
  import org.apache.beam.sdk.values.PCollectionView;
  import org.apache.beam.sdk.values.TupleTag;
  import org.apache.beam.sdk.values.WindowedValue;
  import org.apache.beam.sdk.values.WindowingStrategy;
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  /** Static utility methods that provide {@link DoFnRunner} implementations. */
  @SuppressWarnings({
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class DoFnRunners {
    /**
     * Returns an implementation of {@link DoFnRunner} that for a {@link DoFn}.
     *
     * <p>If the {@link DoFn} observes the window, this runner will explode the windows of a
     * compressed {@link WindowedValue}. It is the responsibility of the runner to perform any key
     * partitioning needed, etc.
     */
    public static <InputT, OutputT> DoFnRunner<InputT, OutputT> simpleRunner(
        PipelineOptions options,
        DoFn<InputT, OutputT> fn,
        SideInputReader sideInputReader,
        WindowedValueMultiReceiver outputManager,
        TupleTag<OutputT> mainOutputTag,
        List<TupleTag<?>> additionalOutputTags,
        StepContext stepContext,
        Coder<InputT> inputCoder,
        Map<TupleTag<?>, Coder<?>> outputCoders,
        WindowingStrategy<?, ?> windowingStrategy,
        DoFnSchemaInformation doFnSchemaInformation,
        Map<String, PCollectionView<?>> sideInputMapping) {
      return new SimpleDoFnRunner<>(
          options,
          fn,
          sideInputReader,
          outputManager,
          mainOutputTag,
          additionalOutputTags,
          stepContext,
          inputCoder,
          outputCoders,
          windowingStrategy,
          doFnSchemaInformation,
          sideInputMapping);
    }
  
    /**
     * Returns an implementation of {@link DoFnRunner} that handles late data dropping.
     *
     * <p>It drops elements from expired windows before they reach the underlying {@link DoFn}.
     */
    public static <K, InputT, OutputT, W extends BoundedWindow>
        DoFnRunner<KeyedWorkItem<K, InputT>, KV<K, OutputT>> lateDataDroppingRunner(
            DoFnRunner<KeyedWorkItem<K, InputT>, KV<K, OutputT>> wrappedRunner,
            TimerInternals timerInternals,
            WindowingStrategy<?, W> windowingStrategy) {
      return new LateDataDroppingDoFnRunner<>(wrappedRunner, windowingStrategy, timerInternals);
    }
  
    /**
     * Returns an implementation of {@link DoFnRunner} that handles late data dropping and garbage
     * collection for stateful {@link DoFn DoFns}.
     *
     * <p>It registers a timer by TimeInternals, and clean all states by StateInternals. It also
     * correctly handles {@link DoFn.RequiresTimeSortedInput} if the provided {@link DoFn} requires
     * this.
     */
    public static <InputT, OutputT, W extends BoundedWindow>
        DoFnRunner<InputT, OutputT> defaultStatefulDoFnRunner(
            DoFn<InputT, OutputT> fn,
            Coder<InputT> inputCoder,
            DoFnRunner<InputT, OutputT> doFnRunner,
            StepContext stepContext,
            WindowingStrategy<?, ?> windowingStrategy,
            CleanupTimer<InputT> cleanupTimer,
            StateCleaner<W> stateCleaner) {
      return defaultStatefulDoFnRunner(
          fn,
          inputCoder,
          doFnRunner,
          stepContext,
          windowingStrategy,
          cleanupTimer,
          stateCleaner,
          false);
    }
  
    /**
     * Returns an implementation of {@link DoFnRunner} that handles late data dropping and garbage
     * collection for stateful {@link DoFn DoFns}.
     *
     * <p>It registers a timer by TimeInternals, and clean all states by StateInternals. If {@code
     * requiresTimeSortedInputSupported} is {@code true} then it also handles {@link
     * DoFn.RequiresTimeSortedInput} if the provided {@link DoFn} requires this. If {@code
     * requiresTimeSortedInputSupported} is {@code false} and the provided {@link DoFn} has {@link
     * DoFn.RequiresTimeSortedInput} this method will throw {@link UnsupportedOperationException}.
     */
    public static <InputT, OutputT, W extends BoundedWindow>
        DoFnRunner<InputT, OutputT> defaultStatefulDoFnRunner(
            DoFn<InputT, OutputT> fn,
            Coder<InputT> inputCoder,
            DoFnRunner<InputT, OutputT> doFnRunner,
            StepContext stepContext,
            WindowingStrategy<?, ?> windowingStrategy,
            CleanupTimer<InputT> cleanupTimer,
            StateCleaner<W> stateCleaner,
            boolean requiresTimeSortedInputSupported) {
      boolean doFnRequiresTimeSortedInput =
          DoFnSignatures.signatureForDoFn(doFnRunner.getFn())
              .processElement()
              .requiresTimeSortedInput();
  
      if (doFnRequiresTimeSortedInput && !requiresTimeSortedInputSupported) {
        throw new UnsupportedOperationException(
            "DoFn.RequiresTimeSortedInput not currently supported by this runner.");
      }
      return new StatefulDoFnRunner<>(
          doFnRunner,
          inputCoder,
          stepContext,
          windowingStrategy,
          cleanupTimer,
          stateCleaner,
          doFnRequiresTimeSortedInput);
    }
  
    public static <InputT, OutputT, RestrictionT>
        ProcessFnRunner<InputT, OutputT, RestrictionT> newProcessFnRunner(
            ProcessFn<InputT, OutputT, RestrictionT, ?, ?> fn,
            PipelineOptions options,
            Collection<PCollectionView<?>> views,
            ReadyCheckingSideInputReader sideInputReader,
            WindowedValueMultiReceiver outputManager,
            TupleTag<OutputT> mainOutputTag,
            List<TupleTag<?>> additionalOutputTags,
            StepContext stepContext,
            @Nullable Coder<KeyedWorkItem<byte[], KV<InputT, RestrictionT>>> inputCoder,
            Map<TupleTag<?>, Coder<?>> outputCoders,
            WindowingStrategy<?, ?> windowingStrategy,
            DoFnSchemaInformation doFnSchemaInformation,
            Map<String, PCollectionView<?>> sideInputMapping) {
      return new ProcessFnRunner<>(
          simpleRunner(
              options,
              fn,
              sideInputReader,
              outputManager,
              mainOutputTag,
              additionalOutputTags,
              stepContext,
              inputCoder,
              outputCoders,
              windowingStrategy,
              doFnSchemaInformation,
              sideInputMapping),
          views,
          sideInputReader);
    }
  }
  