at.storm.bolt.JsonBolt.java Source code

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Here is the source code for at.storm.bolt.JsonBolt.java

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/**
 * 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 at.storm.bolt;

import java.util.Map;

import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.BasicOutputCollector;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.topology.base.BaseBasicBolt;
import org.apache.storm.tuple.Tuple;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

import at.storm.bolt.values.data.JsonBoltData;
import at.storm.bolt.values.statistic.tuple.TupleStatistic;
import at.storm.commons.LanguageDetection;

public class JsonBolt extends BaseBasicBolt {
    public static final String ID = "json-bolt";
    public static final String CONF_LOGGING = ID + ".logging";
    private static final long serialVersionUID = -8847712312925641497L;
    private static final Logger LOG = LoggerFactory.getLogger(JsonBolt.class);

    public static final String PIPELINE_STREAM = "pipeline-stream";
    public static final String TO_REDIS_PUBLISH_STREAM = "not-english-stream";

    private boolean m_logging = false;
    private JsonParser jsonParser;

    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declareStream(PIPELINE_STREAM, JsonBoltData.getSchema());
        declarer.declareStream(TO_REDIS_PUBLISH_STREAM, JsonBoltData.getSchema());
    }

    @SuppressWarnings("rawtypes")
    public void prepare(Map config, TopologyContext context) {
        // Optional set logging
        if (config.get(CONF_LOGGING) != null) {
            m_logging = (Boolean) config.get(CONF_LOGGING);
        } else {
            m_logging = false;
        }

        jsonParser = new JsonParser();

    }

    public void execute(Tuple tuple, BasicOutputCollector collector) {
        String jsonString = tuple.getStringByField("jsonString");
        TupleStatistic tupleStatistic = (TupleStatistic) tuple.getValueByField("tupleStatistic");

        JsonObject jsonObject = (JsonObject) jsonParser.parse(jsonString);

        if (m_logging) {
            LOG.info("JSON: " + jsonObject.toString());
        }

        tupleStatistic.setRealStart(jsonObject.get("timestamp").getAsLong());

        String message = jsonObject.get("msg").getAsString();

        if (!LanguageDetection.isEnglish(message)) {
            JsonObject score = new JsonObject();
            score.addProperty("score", 0);

            jsonObject.add("sentiment", score);

            collector.emit(TO_REDIS_PUBLISH_STREAM, new JsonBoltData(jsonObject, tupleStatistic));
        } else {
            collector.emit(PIPELINE_STREAM, new JsonBoltData(jsonObject, tupleStatistic));
        }

    }

}