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.kudu;
  
  import java.io.IOException;
  import java.lang.reflect.Field;
  import java.nio.ByteBuffer;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  
  import javax.validation.constraints.NotNull;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.apache.apex.malhar.lib.util.PojoUtils;
  import org.apache.apex.malhar.lib.wal.FSWindowDataManager;
  import org.apache.apex.malhar.lib.wal.WindowDataManager;
  import org.apache.hadoop.classification.InterfaceStability;
  import org.apache.kudu.ColumnSchema;
  import org.apache.kudu.Schema;
  import org.apache.kudu.Type;
  import org.apache.kudu.client.Delete;
  import org.apache.kudu.client.Insert;
  import org.apache.kudu.client.KuduClient;
  import org.apache.kudu.client.KuduException;
  import org.apache.kudu.client.KuduSession;
  import org.apache.kudu.client.KuduTable;
  import org.apache.kudu.client.Operation;
  import org.apache.kudu.client.PartialRow;
  import org.apache.kudu.client.Statistics;
  import org.apache.kudu.client.Update;
  import org.apache.kudu.client.Upsert;
  
  import com.datatorrent.api.AutoMetric;
  import com.datatorrent.api.Context;
  import com.datatorrent.api.DefaultInputPort;
  import com.datatorrent.api.Operator;
  import com.datatorrent.api.annotation.Stateless;
  import com.datatorrent.common.util.BaseOperator;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  /**
   * An Abstract operator that would allow concrete implementations to write a POJO value into a given Kudu table.
   * <p>
   * To use this operator, the following needs to be done by the implementor
   * <ol>
   * <li>Create a concrete implementation of this operator and implement the method to define the connection
   * properties to Kudu. The connection properties are set using the {@link ApexKuduConnection} using a builder pattern.
   * </li>
   * <li>Implement the logic how tuples need to ne handled in the event of a reconciliation phase ( i.e. when an
   * operator is resuming back from failure ). See javadoc of the method for more details.</li>
   * <li>Define the payload class</li>
   * </ol>
   * </p>
   * <p>
   * Note that the tuple that is getting processed is not the POJO class. The tuple that is getting processed is the
   * {@link KuduExecutionContext} instance. This is because the operator supports mutation types as a higher level
   * construct than simply writing a POJO into a Kudu table row.
   * </p>
   * <p>
   * Supported mutations are:
   * <ol>
   *      <li>INSERT</li>
   *      <li>UPDATE</li>
   *      <li>UPSERT</li>
   *      <li>DELETE</li>
   * </ol>
   * </p>
   * <p>
   * Please note that the Update mutation allows to change a subset of columns only even though there might be columns
   * that were defined to be non-nullable. This is because the original mutation of type insert would have written the
   * mandatory columns. In such scenarios, the method setDoNotWriteColumns() in {@link KuduExecutionContext} can be
   * used to specify only those columns that need an update. This ways a read and Update pattern can be merged to a
   * simple update pattern thus avoiding a read if required.</p>
   *
   * @since 3.8.0
   * */
  @InterfaceStability.Evolving
  public abstract class AbstractKuduOutputOperator extends BaseOperator
      implements Operator.ActivationListener<Context.OperatorContext>,Operator.CheckpointNotificationListener
  {
  
    private transient ApexKuduConnection apexKuduConnection;
  
    private transient  KuduTable kuduTable;
  
    private transient  KuduSession kuduSession;
  
    private transient KuduClient kuduClientHandle;
  
    private transient Map<String,ColumnSchema> allColumnDefs;
  
    private transient Map<String,Object> kuduColumnBasedGetters;
  
    private Set<String> primaryKeyColumnNames;
  
    private static final transient Logger LOG = LoggerFactory.getLogger(AbstractKuduOutputOperator.class);
  
    @NotNull
    protected WindowDataManager windowDataManager;
  
    private transient long currentWindowId;
  
    private transient boolean isInReplayMode;
  
    private transient boolean isInReconcilingMode;
  
    private transient long reconcilingWindowId;
  
    @AutoMetric
    transient long numInserts;
  
    @AutoMetric
    transient long numUpserts;
  
    @AutoMetric
    transient long numDeletes;
  
    @AutoMetric
    transient long numUpdates;
  
    @AutoMetric
    transient long numOpsErrors;
  
    @AutoMetric
    transient long numBytesWritten;
  
    @AutoMetric
    transient long numRpcErrors;
  
    @AutoMetric
    transient long numWriteOps;
  
    @AutoMetric
    transient long numWriteRPCs;
  
    @AutoMetric
    long totalOpsErrors = 0;
  
    @AutoMetric
    long totalBytesWritten = 0;
  
    @AutoMetric
    long totalRpcErrors = 0;
  
    @AutoMetric
    long totalWriteOps = 0;
  
    @AutoMetric
    long totalWriteRPCs = 0;
  
    @AutoMetric
    long totalInsertsSinceStart;
  
    @AutoMetric
    long totalUpsertsSinceStart;
  
    @AutoMetric
    long totalDeletesSinceStart;
  
    @AutoMetric
    long totalUpdatesSinceStart;
  
    public final transient DefaultInputPort<KuduExecutionContext> input = new DefaultInputPort<KuduExecutionContext>()
    {
      @Override
      public void process(KuduExecutionContext kuduExecutionContext)
      {
        processTuple(kuduExecutionContext);
      }
    }; // end input port implementation
  
    public void processTuple(KuduExecutionContext kuduExecutionContext)
    {
      if ( isInReconcilingMode || isInReplayMode) {
        if ( !isEligibleForPassivationInReconcilingWindow(kuduExecutionContext, currentWindowId)) {
          return;
        }
      }
      KuduMutationType mutationType = kuduExecutionContext.getMutationType();
      switch (mutationType) {
        case DELETE:
          processForDelete(kuduExecutionContext);
          numDeletes += 1;
          totalDeletesSinceStart += 1;
          break;
        case INSERT:
          processForInsert(kuduExecutionContext);
          numInserts += 1;
          totalInsertsSinceStart += 1;
          break;
        case UPDATE:
          processForUpdate(kuduExecutionContext);
          numUpdates += 1;
          totalUpdatesSinceStart += 1;
          break;
        case UPSERT:
          processForUpsert(kuduExecutionContext);
          numUpserts += 1;
          totalUpsertsSinceStart += 1;
          break;
        default:
          break;
      }
    }
  
    /***
     * Sets the values from the Pojo into the Kudu mutation object.
     * @param currentOperation The operation instance that represents the current mutation. This will be applied to the
     *                         current session
     * @param kuduExecutionContext The tuple that contains the payload as well as other information like mutation type etc
     */
    @SuppressWarnings(value = "unchecked")
    private void performCommonProcessing(Operation currentOperation, KuduExecutionContext kuduExecutionContext)
    {
      currentOperation.setExternalConsistencyMode(kuduExecutionContext.getExternalConsistencyMode());
      Long propagatedTimeStamp = kuduExecutionContext.getPropagatedTimestamp();
      if ( propagatedTimeStamp != null) { // set propagation timestamp only if enabled
        currentOperation.setPropagatedTimestamp(propagatedTimeStamp);
      }
      PartialRow partialRow = currentOperation.getRow();
      Object payload = kuduExecutionContext.getPayload();
      Set<String> doNotWriteColumns = kuduExecutionContext.getDoNotWriteColumns();
      if (doNotWriteColumns == null) {
        doNotWriteColumns = new HashSet<>();
      }
      for (String columnName: kuduColumnBasedGetters.keySet()) {
        if ( doNotWriteColumns.contains(columnName)) {
          continue;
        }
        ColumnSchema columnSchema = allColumnDefs.get(columnName);
        Type dataType = columnSchema.getType();
        try {
          switch (dataType) {
            case STRING:
              PojoUtils.Getter<Object, String> stringGetter = ((PojoUtils.Getter<Object, String>)kuduColumnBasedGetters
                  .get(columnName));
              if (stringGetter != null) {
                final String stringValue = stringGetter.get(payload);
                if (stringValue != null) {
                  partialRow.addString(columnName, stringValue);
                }
              }
              break;
            case BINARY:
              PojoUtils.Getter<Object, ByteBuffer> byteBufferGetter = ((PojoUtils.Getter<Object, ByteBuffer>)
                  kuduColumnBasedGetters.get(columnName));
              if (byteBufferGetter != null) {
                final ByteBuffer byteBufferValue = byteBufferGetter.get(payload);
                if (byteBufferValue != null) {
                  partialRow.addBinary(columnName, byteBufferValue);
                }
              }
              break;
            case BOOL:
              PojoUtils.GetterBoolean<Object> boolGetter = ((PojoUtils.GetterBoolean<Object>)kuduColumnBasedGetters.get(
                  columnName));
              if (boolGetter != null) {
                final boolean boolValue = boolGetter.get(payload);
                partialRow.addBoolean(columnName, boolValue);
              }
              break;
            case DOUBLE:
              PojoUtils.GetterDouble<Object> doubleGetter = ((PojoUtils.GetterDouble<Object>)kuduColumnBasedGetters.get(
                  columnName));
              if (doubleGetter != null) {
                final double doubleValue = doubleGetter.get(payload);
                partialRow.addDouble(columnName, doubleValue);
              }
              break;
            case FLOAT:
              PojoUtils.GetterFloat<Object> floatGetter = ((PojoUtils.GetterFloat<Object>)kuduColumnBasedGetters.get(
                  columnName));
              if (floatGetter != null) {
                final float floatValue = floatGetter.get(payload);
                partialRow.addFloat(columnName, floatValue);
              }
              break;
            case INT8:
              PojoUtils.GetterByte<Object> byteGetter = ((PojoUtils.GetterByte<Object>)kuduColumnBasedGetters.get(
                  columnName));
              if (byteGetter != null) {
                final byte byteValue = byteGetter.get(payload);
                partialRow.addByte(columnName, byteValue);
              }
              break;
            case INT16:
              PojoUtils.GetterShort<Object> shortGetter = ((PojoUtils.GetterShort<Object>)kuduColumnBasedGetters.get(
                  columnName));
              if (shortGetter != null) {
                final short shortValue = shortGetter.get(payload);
                partialRow.addShort(columnName, shortValue);
              }
              break;
            case INT32:
              PojoUtils.GetterInt<Object> intGetter = ((PojoUtils.GetterInt<Object>)
                  kuduColumnBasedGetters.get(columnName));
              if (intGetter != null) {
                final int intValue = intGetter.get(payload);
                partialRow.addInt(columnName, intValue);
              }
              break;
            case INT64:
            case UNIXTIME_MICROS:
              PojoUtils.GetterLong<Object> longGetter = ((PojoUtils.GetterLong<Object>)kuduColumnBasedGetters.get(
                  columnName));
              if (longGetter != null) {
                final long longValue = longGetter.get(payload);
                partialRow.addLong(columnName, longValue);
              }
              break;
            default:
              LOG.error(columnName + " is not of the supported data type");
              throw new UnsupportedOperationException("Kudu does not support data type for column " + columnName);
          }
        } catch ( Exception ex ) {
          LOG.error(" Exception while fetching the value of " + columnName + " because " + ex.getMessage());
          partialRow.setNull(columnName);
        }
      }
      try {
        kuduSession.apply(currentOperation);
      } catch (KuduException e) {
        throw new RuntimeException("Could not execute operation because " + e.getMessage(), e);
      }
    }
  
    protected void processForUpdate(KuduExecutionContext kuduExecutionContext)
    {
      Update thisUpdate = kuduTable.newUpdate();
      performCommonProcessing(thisUpdate,kuduExecutionContext);
    }
  
  
    protected void processForUpsert(KuduExecutionContext kuduExecutionContext)
    {
      Upsert thisUpsert = kuduTable.newUpsert();
      performCommonProcessing(thisUpsert,kuduExecutionContext);
    }
  
  
  
    protected void processForDelete(KuduExecutionContext kuduExecutionContext)
    {
      Delete thisDelete = kuduTable.newDelete();
      // Kudu does not allow column values to be set in case of a delete mutation
      Set<String> doNotWriteCols = kuduExecutionContext.getDoNotWriteColumns();
      if ( doNotWriteCols == null) {
        doNotWriteCols = new HashSet<>();
      }
      doNotWriteCols.clear();
      for (String columnName : allColumnDefs.keySet()) {
        if ( !(primaryKeyColumnNames.contains(columnName))) {
          doNotWriteCols.add(columnName);
        }
      }
      kuduExecutionContext.setDoNotWriteColumns(doNotWriteCols);
      performCommonProcessing(thisDelete,kuduExecutionContext);
    }
  
  
    protected void processForInsert(KuduExecutionContext kuduExecutionContext)
    {
      Insert thisInsert = kuduTable.newInsert();
      performCommonProcessing(thisInsert,kuduExecutionContext);
    }
  
    @Override
    public void activate(Context.OperatorContext context)
    {
      ApexKuduConnection.ApexKuduConnectionBuilder apexKuduConnectionBuilder = getKuduConnectionConfig();
      apexKuduConnection = apexKuduConnectionBuilder.build();
      checkNotNull(apexKuduConnection,"Kudu connection cannot be null");
      kuduTable = apexKuduConnection.getKuduTable();
      kuduSession = apexKuduConnection.getKuduSession();
      kuduClientHandle = apexKuduConnection.getKuduClient();
      checkNotNull(kuduTable,"Kudu Table cannot be null");
      checkNotNull(kuduSession, "Kudu session cannot be null");
      allColumnDefs = new HashMap();
      primaryKeyColumnNames = new HashSet<>();
      kuduColumnBasedGetters = new HashMap();
      buildGettersForPojoPayload();
      reconcilingWindowId = Stateless.WINDOW_ID;
      // The operator is working in a replay mode where the upstream buffer is re-streaming the tuples
      // Note that there are two windows that need special core. The window that is being replayed and the subsequent
      // window that might have resulted in a crash which we are referring as reconciling window
      if ( (context.getValue(Context.OperatorContext.ACTIVATION_WINDOW_ID) != Stateless.WINDOW_ID) &&
          context.getValue(Context.OperatorContext.ACTIVATION_WINDOW_ID) <
          windowDataManager.getLargestCompletedWindow()) {
        reconcilingWindowId = windowDataManager.getLargestCompletedWindow() + 1;
      }
  
      if ( (context.getValue(Context.OperatorContext.ACTIVATION_WINDOW_ID) != Stateless.WINDOW_ID) &&
          context.getValue(Context.OperatorContext.ACTIVATION_WINDOW_ID) ==
          windowDataManager.getLargestCompletedWindow()) {
        reconcilingWindowId = windowDataManager.getLargestCompletedWindow();
      }
    }
  
    @Override
    public void deactivate()
    {
      try {
        apexKuduConnection.close();
      } catch (Exception e) {
        LOG.error("Could not close kudu session and resources because " + e.getMessage(), e);
      }
    }
  
    @Override
    public void beforeCheckpoint(long l)
    {
      // Nothing to be done here. Child classes can use this if required
    }
  
    @Override
    public void checkpointed(long l)
    {
      // Nothing to be done here. Child classes can use this if required
    }
  
    @Override
    public void committed(long windowId)
    {
      try {
        windowDataManager.committed(windowId);
      } catch (IOException e) {
        throw new RuntimeException("Error while committing the window id " + windowId + " because " + e.getMessage(), e );
      }
    }
  
    @Override
    public void setup(Context.OperatorContext context)
    {
      super.setup(context);
      windowDataManager = getWindowDataManager();
      if ( windowDataManager == null) {
        windowDataManager = new FSWindowDataManager();
      }
      windowDataManager.setup(context);
    }
  
    @Override
    public void teardown()
    {
      windowDataManager.teardown();
    }
  
    @Override
    public void beginWindow(long windowId)
    {
      super.beginWindow(windowId);
      currentWindowId = windowId;
      if ( currentWindowId != Stateless.WINDOW_ID) { // if it is not the first window of the application
        if (currentWindowId > reconcilingWindowId) {
          isInReplayMode = false;
          isInReconcilingMode = false;
        }
        if (currentWindowId == reconcilingWindowId) {
          isInReconcilingMode = true;
          isInReplayMode = false;
        }
        if (currentWindowId < reconcilingWindowId) {
          isInReconcilingMode = false;
          isInReplayMode = true;
        }
      }
      numDeletes = 0;
      numInserts = 0;
      numUpdates = 0;
      numUpserts = 0;
    }
  
    @Override
    public void endWindow()
    {
      try {
        kuduSession.flush();
      } catch (KuduException e) {
        throw new RuntimeException("Could not flush kudu session on an end window boundary " + e.getMessage(), e);
      }
      if ( currentWindowId > windowDataManager.getLargestCompletedWindow()) {
        try {
          windowDataManager.save(currentWindowId,currentWindowId);
        } catch (IOException e) {
          throw new RuntimeException("Error while persisting the current window state " + currentWindowId +
              " because " + e.getMessage(), e);
        }
      }
      numOpsErrors = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.OPS_ERRORS) -
        totalOpsErrors;
      numBytesWritten = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.BYTES_WRITTEN) -
        totalBytesWritten;
      numRpcErrors = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.RPC_ERRORS) -
        totalRpcErrors;
      numWriteOps = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.WRITE_OPS) -
        totalWriteOps;
      numWriteRPCs = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.WRITE_RPCS) - totalWriteOps;
      totalOpsErrors = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.OPS_ERRORS);
      totalBytesWritten = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.BYTES_WRITTEN);
      totalRpcErrors = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.RPC_ERRORS);
      totalWriteOps = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.WRITE_OPS);
      totalWriteRPCs = kuduClientHandle.getStatistics().getClientStatistic(Statistics.Statistic.WRITE_RPCS);
    }
  
    private void buildGettersForPojoPayload()
    {
      Class payloadClass = getTuplePayloadClass();
      checkNotNull(payloadClass,"Payload class cannot be null");
      Field[] classFields = payloadClass.getDeclaredFields();
      Schema schemaInfo = kuduTable.getSchema();
      List<ColumnSchema> allColumns = schemaInfo.getColumns();
      Set<String> allKuduTableColumnNames = new HashSet<>();
      Map<String,ColumnSchema> normalizedColumns = new HashMap();
      for ( ColumnSchema aColumnDef : allColumns) {
        allColumnDefs.put(aColumnDef.getName(), aColumnDef);
        normalizedColumns.put(aColumnDef.getName().toLowerCase(), aColumnDef);
        allKuduTableColumnNames.add(aColumnDef.getName().toLowerCase());
      }
      List<ColumnSchema> primaryKeyColumns = schemaInfo.getPrimaryKeyColumns();
      for (ColumnSchema primaryKeyInfo : primaryKeyColumns) {
        primaryKeyColumnNames.add(primaryKeyInfo.getName());
      }
      Map<String,String> columnNameOverrides = getOverridingColumnNameMap();
      if (columnNameOverrides == null) {
        columnNameOverrides = new HashMap(); // to avoid null checks further down the line
      }
      for ( Field aFieldDef : classFields) {
        String currentFieldName = aFieldDef.getName().toLowerCase();
        if (allKuduTableColumnNames.contains(currentFieldName)) {
          extractGetterForColumn(normalizedColumns.get(currentFieldName),aFieldDef);
        } else {
          if (columnNameOverrides.containsKey(aFieldDef.getName())) {
            extractGetterForColumn(normalizedColumns.get(columnNameOverrides.get(aFieldDef.getName()).toLowerCase()),
                aFieldDef);
          } else if (columnNameOverrides.containsKey(aFieldDef.getName().toLowerCase())) {
            extractGetterForColumn(normalizedColumns.get(columnNameOverrides.get(aFieldDef.getName().toLowerCase())
                .toLowerCase()),aFieldDef);
          }
        }
      }
    }
  
    /***
     * Used to build a getter for the given schema column from the POJO field definition
     * @param columnSchema The Kudu column definition
     * @param fieldDefinition The POJO field definition
     */
    private void extractGetterForColumn(ColumnSchema columnSchema, Field fieldDefinition)
    {
      Type columnType = columnSchema.getType();
      Class pojoClass = getTuplePayloadClass();
      Object getter = null;
      switch ( columnType ) {
        case BINARY:
          getter = PojoUtils.createGetter(pojoClass, fieldDefinition.getName(), ByteBuffer.class);
          break;
        case STRING:
          getter = PojoUtils.createGetter(pojoClass, fieldDefinition.getName(), String.class);
          break;
        case BOOL:
          getter = PojoUtils.createGetterBoolean(pojoClass, fieldDefinition.getName());
          break;
        case DOUBLE:
          getter = PojoUtils.createGetterDouble(pojoClass, fieldDefinition.getName());
          break;
        case FLOAT:
          getter = PojoUtils.createGetterFloat(pojoClass, fieldDefinition.getName());
          break;
        case INT8:
          getter = PojoUtils.createGetterByte(pojoClass, fieldDefinition.getName());
          break;
        case INT16:
          getter = PojoUtils.createGetterShort(pojoClass, fieldDefinition.getName());
          break;
        case INT32:
          getter = PojoUtils.createGetterInt(pojoClass, fieldDefinition.getName());
          break;
        case INT64:
        case UNIXTIME_MICROS:
          getter = PojoUtils.createGetterLong(pojoClass, fieldDefinition.getName());
          break;
        default:
          LOG.error(fieldDefinition.getName() + " has a data type that is not yet supported");
          throw new UnsupportedOperationException(fieldDefinition.getName() + " does not have a compatible data type");
      }
      if (getter != null) {
        kuduColumnBasedGetters.put(columnSchema.getName(),getter);
      }
    }
  
  
    public static ApexKuduConnection.ApexKuduConnectionBuilder usingKuduConnectionBuilder()
    {
      return new ApexKuduConnection.ApexKuduConnectionBuilder();
    }
  
    public WindowDataManager getWindowDataManager()
    {
      return windowDataManager;
    }
  
    public void setWindowDataManager(WindowDataManager windowDataManager)
    {
      this.windowDataManager = windowDataManager;
    }
  
    /***
     * Allows to map a POJO field name to a Kudu Table column name. This is useful in case
     * the POJO field name can't be changed to an unconventional name ( ex: if kudu column names have underscores ). It
     * can be also useful when the developer does not want to declare a new POJO but reuse an existing POJO.
     * Note that the key in the map is the name of the field in the POJO and
     * the value part is used to denote the name of the kudu column
     * @return The map giving the mapping from POJO field name to the Kudu column name
     */
    protected Map<String,String> getOverridingColumnNameMap()
    {
      return new HashMap<>();
    }
  
    abstract ApexKuduConnection.ApexKuduConnectionBuilder getKuduConnectionConfig();
  
    /***
     * Represents the Tuple payload class that maps to a Kudu table row. Note that the POJO fields are mapped to the
     * kudu column names is a lenient way. For example, the mapping of POJO field names to the kudu columns is done
     * in a case-insensitive way.
     * @return The class that will be used to map to a row in the given Kudu table.
     */
    protected abstract Class getTuplePayloadClass();
  
    /***
     * This is used to give control to the concrete implementation of this operator how to resolve whether to write a
     * mutation into a given kudu table in the event of a failure and the operator subsequently resumes. This window
     * is marked as a reconciling window. It is only for this reconciling window that we need to give control to the
     * concrete operator implementor how to actually resolve if the entry needs to be excuted as a mutation in Kudu.
     * @param executionContext The tuple which represents the execution context along with the payload
     * @param reconcilingWindowId The window Id of the reconciling window
     * @return true if we would like the entry to result in a mutation in the Kudu table.
     */
    protected abstract boolean isEligibleForPassivationInReconcilingWindow(KuduExecutionContext executionContext,
        long reconcilingWindowId);
  }
  
  