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.apex.malhar.contrib.nifi;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Map;
  
  import org.apache.apex.malhar.lib.wal.WindowDataManager;
  import org.apache.nifi.remote.client.SiteToSiteClient;
  import org.apache.nifi.remote.protocol.DataPacket;
  import org.apache.nifi.stream.io.StreamUtils;
  
  /**
   * Input adapter operator which consumes data from NiFi and produces NiFiDataPackets
   * where each NiFiDataPacket contains a byte array of content and a Map of attributes.
   *
   * @displayName NiFi Input Operator
   * @category Messaging
   * @tags input operator
   *
   *
   * @since 3.4.0
   */
  public class NiFiSinglePortInputOperator extends AbstractNiFiSinglePortInputOperator<NiFiDataPacket>
  {
  
    // required by Kyro serialization
    private NiFiSinglePortInputOperator()
    {
      super(null, null);
    }
  
    /**
     *
     * @param siteToSiteBuilder the builder for a NiFi SiteToSiteClient
     * @param windowDataManager a WindowDataManager to save and load state for windows of tuples
     */
    public NiFiSinglePortInputOperator(final SiteToSiteClient.Builder siteToSiteBuilder,
        final WindowDataManager windowDataManager)
    {
      super(siteToSiteBuilder, windowDataManager);
    }
  
    @Override
    protected NiFiDataPacket createTuple(final DataPacket dataPacket) throws IOException
    {
      // read the data into a byte array and wrap it with the attributes into a NiFiDataPacket
      final InputStream inStream = dataPacket.getData();
      final byte[] data = new byte[(int)dataPacket.getSize()];
      StreamUtils.fillBuffer(inStream, data);
  
      final Map<String, String> attributes = dataPacket.getAttributes();
      return new StandardNiFiDataPacket(data, attributes);
    }
  
  }
  