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.dataflow.worker;
  
  import com.google.api.services.dataflow.model.CounterUpdate;
  import com.google.api.services.dataflow.model.SourceOperationRequest;
  import com.google.api.services.dataflow.model.SourceOperationResponse;
  import com.google.api.services.dataflow.model.SourceSplitRequest;
  import java.io.Closeable;
  import java.util.Collections;
  import org.apache.beam.runners.core.metrics.ExecutionStateTracker;
  import org.apache.beam.runners.core.metrics.ExecutionStateTracker.ExecutionState;
  import org.apache.beam.runners.dataflow.worker.counters.CounterSet;
  import org.apache.beam.sdk.options.PipelineOptions;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /** An executor for a source operation, defined by a {@code SourceOperationRequest}. */
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class WorkerCustomSourceOperationExecutor implements SourceOperationExecutor {
    private static final Logger LOG =
        LoggerFactory.getLogger(WorkerCustomSourceOperationExecutor.class);
    private final PipelineOptions options;
    private final SourceOperationRequest request;
    private final CounterSet counters;
    private SourceOperationResponse response;
  
    private ExecutionStateTracker executionStateTracker;
    private ExecutionState executionState;
  
    public WorkerCustomSourceOperationExecutor(
        PipelineOptions options,
        SourceOperationRequest request,
        CounterSet counters,
        DataflowExecutionContext executionContext,
        DataflowOperationContext operationContext) {
      this.counters = counters;
      this.options = options;
      this.request = request;
      this.executionStateTracker = executionContext.getExecutionStateTracker();
      this.executionState = operationContext.newExecutionState(getOperationDescription(request));
    }
  
    @Override
    public CounterSet getOutputCounters() {
      return counters;
    }
  
    private static String getOperationDescription(SourceOperationRequest request) {
      if (request.getSplit() != null) {
        return "split";
      } else {
        throw new UnsupportedOperationException("Unsupported source operation request: " + request);
      }
    }
  
    @Override
    public void execute() throws Exception {
      LOG.debug("Executing source operation");
      try (Closeable stateTrackerCloser = executionStateTracker.activate()) {
        try (Closeable stateCloser = executionStateTracker.enterState(executionState)) {
          SourceSplitRequest split = request.getSplit();
          if (split != null) {
            this.response = WorkerCustomSources.performSplit(split, options);
          } else {
            throw new UnsupportedOperationException(
                "Unsupported source operation request: " + request);
          }
        }
      }
      LOG.debug("Source operation execution complete");
    }
  
    @Override
    public SourceOperationResponse getResponse() {
      return response;
    }
  
    @Override
    public Iterable<CounterUpdate> extractMetricUpdates() {
      return Collections.emptyList();
    }
  }
  