Neo4jHttpGraphHelper.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
 *
 *   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.streams.neo4j.http;

import org.apache.streams.graph.HttpGraphHelper;
import org.apache.streams.jackson.StreamsJacksonMapper;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.javatuples.Pair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.Map;
import java.util.Objects;

/**
 * Supporting class for interacting with neo4j via rest API.
 */
public class Neo4jHttpGraphHelper implements HttpGraphHelper {

  private static final ObjectMapper MAPPER = StreamsJacksonMapper.getInstance();

  private static final Logger LOGGER = LoggerFactory.getLogger(Neo4jHttpGraphHelper.class);

  private static final String statementKey = "statement";
  private static final String queryKey = "query";
  private static final String paramsKey = "parameters";
  private static final String propsKey = "props";

  /**
   * readDataStatement neo4j rest json read data payload.
   *
   * @param queryPlusParameters (query, parameter map)
   * @return ObjectNode
   */
  public ObjectNode readData(Pair<String, Map<String, Object>> queryPlusParameters) {

    LOGGER.debug("readData: ", queryPlusParameters);

    Objects.requireNonNull(queryPlusParameters);
    Objects.requireNonNull(queryPlusParameters.getValue0());

    ObjectNode request = MAPPER.createObjectNode();

    request.put(queryKey, queryPlusParameters.getValue0());

    if( queryPlusParameters.getValue1() != null && queryPlusParameters.getValue1().size() > 0) {
      ObjectNode params = MAPPER.convertValue(queryPlusParameters.getValue1(), ObjectNode.class);
      request.put(paramsKey, params);
    }

    LOGGER.debug("readData: ", request);

    return request;
  }

  /**
   * writeDataStatement neo4j rest json write data payload.
   *
   * @param queryPlusParameters (query, parameter map)
   * @return ObjectNode
   */
  public ObjectNode writeData(Pair<String, Map<String, Object>> queryPlusParameters) {

    LOGGER.debug("writeData: ", queryPlusParameters);

    Objects.requireNonNull(queryPlusParameters);
    Objects.requireNonNull(queryPlusParameters.getValue0());

    ObjectNode request = MAPPER.createObjectNode();

    request.put(statementKey, queryPlusParameters.getValue0());

    if( queryPlusParameters.getValue1() != null && queryPlusParameters.getValue1().size() > 0) {
      ObjectNode params = MAPPER.convertValue(queryPlusParameters.getValue1(), ObjectNode.class);
      request.put(paramsKey, params);
    } else {
      request.put(paramsKey, MAPPER.createObjectNode());
    }

    LOGGER.debug("writeData: ", request);

    return request;
  }


}