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.flink.translation.wrappers.streaming.io;
  
  import java.util.List;
  import org.apache.beam.sdk.coders.CoderException;
  import org.apache.beam.sdk.testing.TestStream;
  import org.apache.beam.sdk.transforms.SerializableFunction;
  import org.apache.beam.sdk.transforms.windowing.GlobalWindow;
  import org.apache.beam.sdk.transforms.windowing.PaneInfo;
  import org.apache.beam.sdk.values.TimestampedValue;
  import org.apache.beam.sdk.values.WindowedValue;
  import org.apache.beam.sdk.values.WindowedValues;
  import org.apache.flink.streaming.api.functions.source.RichSourceFunction;
  import org.apache.flink.streaming.api.watermark.Watermark;
  import org.joda.time.Instant;
  
  /** Flink source for executing {@link org.apache.beam.sdk.testing.TestStream}. */
  public class TestStreamSource<T> extends RichSourceFunction<WindowedValue<T>> {
  
    private final SerializableFunction<byte[], TestStream<T>> testStreamDecoder;
    private final byte[] payload;
  
    private volatile boolean isRunning = true;
  
    public TestStreamSource(
        SerializableFunction<byte[], TestStream<T>> testStreamDecoder, byte[] payload) {
      this.testStreamDecoder = testStreamDecoder;
      this.payload = payload;
    }
  
    @Override
    public void run(SourceContext<WindowedValue<T>> ctx) throws CoderException {
      TestStream<T> testStream = testStreamDecoder.apply(payload);
      List<TestStream.Event<T>> events = testStream.getEvents();
  
      for (int eventId = 0; isRunning && eventId < events.size(); eventId++) {
        TestStream.Event<T> event = events.get(eventId);
  
        synchronized (ctx.getCheckpointLock()) {
          if (event instanceof TestStream.ElementEvent) {
            for (TimestampedValue<T> element : ((TestStream.ElementEvent<T>) event).getElements()) {
              Instant timestamp = element.getTimestamp();
              WindowedValue<T> value =
                  WindowedValues.of(
                      element.getValue(), timestamp, GlobalWindow.INSTANCE, PaneInfo.NO_FIRING);
              ctx.collectWithTimestamp(value, timestamp.getMillis());
            }
          } else if (event instanceof TestStream.WatermarkEvent) {
            long millis = ((TestStream.WatermarkEvent<T>) event).getWatermark().getMillis();
            ctx.emitWatermark(new Watermark(millis));
          } else if (event instanceof TestStream.ProcessingTimeEvent) {
            // There seems to be no clean way to implement this
            throw new UnsupportedOperationException(
                "Advancing Processing time is not supported by the Flink Runner.");
          } else {
            throw new IllegalStateException("Unknown event type " + event);
          }
        }
      }
    }
  
    @Override
    public void cancel() {
      this.isRunning = false;
    }
  }
  