MatchBolt.java

package nl.us2.cloudpelican.stormprocessor;

/**
 * Created by robin on 07/06/15.
 */

import backtype.storm.Config;
import backtype.storm.task.OutputCollector;
import backtype.storm.task.TopologyContext;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.topology.base.BaseRichBolt;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Tuple;
import backtype.storm.tuple.Values;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import org.apache.commons.codec.binary.Base64;
import org.apache.storm.http.HttpResponse;
import org.apache.storm.http.client.HttpClient;
import org.apache.storm.http.client.methods.HttpGet;
import org.apache.storm.http.impl.client.HttpClientBuilder;
import org.apache.storm.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import storm.starter.util.TupleHelpers;

import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

import static backtype.storm.utils.Utils.DEFAULT_STREAM_ID;

/**
 *
 * @author robin
 */
public class MatchBolt extends BaseRichBolt {

    OutputCollector _collector;
    HashMap<String, Filter> filters;
    JsonParser jsonParser;
    private boolean localMode = false;
    private String regex;
    private Settings settings;

    private static final Logger LOG = LoggerFactory.getLogger(MatchBolt.class);

    public MatchBolt(Settings settings) {
        super();
        filters = null;
        this.settings = settings;
        this.regex = this.settings.get("match_regex");
    }

    public void prepare(Map conf, TopologyContext context, OutputCollector collector) {
        _collector = collector;
        jsonParser = new JsonParser();

        // Local mode
        if (regex != null && !regex.trim().isEmpty()) {
            LOG.info("Setting up local regex " + regex);
            localMode = true;
            JsonObject obj = new JsonObject();
            String fakeId = UUID.randomUUID().toString();
            obj.addProperty("id", fakeId);
            obj.addProperty("regex", regex);
            filters = new HashMap<String, Filter>();
            filters.put(fakeId, new Filter(obj));
            LOG.info("Setup up local regex " + regex);
        }
    }

    public void execute(Tuple tuple) {
        try {
            if (TupleHelpers.isTickTuple(tuple)) {
                executeTick();
            } else {
                executeTuple(tuple);
            }
        } catch (Exception e) {
            LOG.error("Unexpected error in execute", e);
        }
        _collector.ack(tuple);
    }

    public void executeTick() {
//        long start = new Date().getTime();
        loadFilters();
        // Once a minute
        if (new Date().getTime()/1000L % 60 == 0) {
            dispatchOutlierChecks();
        }
//        LOG.info("Tick took " + (new Date().getTime() - start));
    }

    protected void dispatchOutlierChecks() {
        if (!Boolean.parseBoolean(settings.getOrDefault("outlier_detection_enabled", "true"))) {
            return;
        }
//        long start = new Date().getTime();
        for (Filter filter : getFilters().values()) {
            _collector.emit("dispatch_outlier_checks", new Values(filter.Id()));
        }
//        LOG.info("Outliers dispatch took " + (new Date().getTime() - start));
    }

    protected void loadFilters() {
        // Do not execute in local mode
        if (localMode) {
            return;
        }

        // Init
//        long start = new Date().getTime();
        if (filters == null) {
            filters = new HashMap<String, Filter>();
        }

        // Load
        boolean swapFilters = false;
        try {
            HashMap<String, Filter> tmp = new HashMap<String, Filter>();
            HttpClient client = HttpClientBuilder.create()/*.setDefaultCredentialsProvider(credentialsProvider)*/.build();

            String url = settings.get("supervisor_host") + "filter";
            LOG.debug(url);
            HttpGet get = new HttpGet(url);
            String token = new String(Base64.encodeBase64((settings.get("supervisor_username") + ":" + settings.get("supervisor_password")).getBytes()));
            LOG.debug(token);
            get.setHeader("Authorization", "Basic " + token);

            HttpResponse resp = client.execute(get);
            String body = EntityUtils.toString(resp.getEntity());
            LOG.debug(body);
            JsonObject outer = jsonParser.parse(body).getAsJsonObject();
            JsonArray arr = outer.get("filters").getAsJsonArray();
            for (JsonElement elm : arr) {
                try {
                    JsonObject filter = elm.getAsJsonObject();
                    Filter f = new Filter(filter);
                    if (!f.isValid()) {
                        continue;
                    }
                    if (!filters.containsKey(f.Id())) {
                        LOG.info("Loaded filter " + filter.toString());
                        swapFilters = true;
                    }
                    tmp.put(f.Id(), f);
                } catch (Exception fe) {
                    LOG.error("Failed to load filter", fe);
                    fe.printStackTrace();
                }
            }

            // Swap
            if (swapFilters || filters.size() != tmp.size()) {
                LOG.info("Swapping filter sets");
                filters = tmp;
                for (Filter filter : filters.values()) {
                    filter.compileRegex();
                }
                LOG.info("Compiled filters");
            }
        } catch (Exception e) {
            LOG.error("Failed to load filters", e);
            e.printStackTrace();
        }
//        LOG.info("Loading filters took " + (new Date().getTime() - start));
    }

    protected HashMap<String, Filter> getFilters() {
        if (filters == null) {
            loadFilters();
        }
        return filters;
    }

    public Map<String, Object> getComponentConfiguration() {
        Config conf = new Config();
        int tickFrequencyInSeconds = 1;
        conf.put(Config.TOPOLOGY_TICK_TUPLE_FREQ_SECS, tickFrequencyInSeconds);
        return conf;
    }


    public void executeTuple(Tuple tuple) {
        String msg = tuple.getStringByField("_raw");

        // Match filters
        for (Filter filter : getFilters().values()) {
            // @todo A lot of filters match case-insensitive, so executing 1 toLowerCase() for those who need it will improve efficiency as well
            if (filter.matches(msg)) {
                // Emit match
                _collector.emit(DEFAULT_STREAM_ID, new Values(filter.Id(), tuple.getLongByField("ts"), msg)); // Message
                _collector.emit("match_stats", new Values(filter.Id(), tuple.getLongByField("ts"), MetricsEnum.MATCH.getMask(), 1L)); // Counters
            }
        }
        // No ack, is handled in outer
    }

    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("filter_id", "ts", "msg"));
        declarer.declareStream("match_stats", new Fields("filter_id", "ts", "metric", "increment"));
        if (Boolean.parseBoolean(settings.getOrDefault("outlier_detection_enabled", "true"))) {
            declarer.declareStream("dispatch_outlier_checks", new Fields("filter_id"));
        }
    }
}