contrib/src/main/java/com/datatorrent/contrib/redis/RedisMapAsValueInputOperator.java

/**
 * 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 com.datatorrent.contrib.redis;

import java.util.Map;

import com.datatorrent.lib.util.KeyValPair;

/**
 * This is the an implementation of a Redis input operator It takes in keys to
 * fetch and emits Values stored as Maps in Redis i.e. when value datatype in
 * Redis is HashMap
 *
 * @displayName Redis Input Operator for Map
 * @category Store
 * @tags input operator, key value
 * @since 3.1.0
 *
 */

public class RedisMapAsValueInputOperator extends AbstractRedisInputOperator<KeyValPair<String, Map<String, String>>>
{
  @Override
  public void processTuples()
  {
    for (String key : keys) {
      if (store.getType(key).equals("hash")) {
        Map<String, String> mapValue = store.getMap(key);
        outputPort.emit(new KeyValPair<String, Map<String, String>>(key, mapValue));
      }
    }
    keys.clear();
  }

  @Override
  public KeyValPair<String, Map<String, String>> convertToTuple(Map<Object, Object> o)
  {
    // Do nothing for the override, Emit already handled in processTuples
    return null;
  }
}