com.linkedin.pinot.routing.PercentageBasedRoutingTableSelector.java Source code

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Here is the source code for com.linkedin.pinot.routing.PercentageBasedRoutingTableSelector.java

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/**
 * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * Licensed 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.linkedin.pinot.routing;

import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import java.util.Set;
import org.apache.commons.configuration.Configuration;
import org.apache.commons.configuration.ConfigurationMap;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class PercentageBasedRoutingTableSelector implements RoutingTableSelector {
    private static Logger LOGGER = LoggerFactory.getLogger(PercentageBasedRoutingTableSelector.class);
    private static final String TABLE_KEY = "table";

    private final Map<String, Integer> _percentMap = new HashMap<>(1);
    private final Random _random = new Random();

    public PercentageBasedRoutingTableSelector() {
    }

    public void init(Configuration configuration) {
        try {
            Configuration tablesConfig = configuration.subset(TABLE_KEY);
            if (tablesConfig == null || tablesConfig.isEmpty()) {
                LOGGER.info("No specific table configuration. Using 0% LLC for all tables");
                return;
            }
            ConfigurationMap cmap = new ConfigurationMap(tablesConfig);
            Set<Map.Entry<String, Integer>> mapEntrySet = cmap.entrySet();
            for (Map.Entry<String, Integer> entry : mapEntrySet) {
                LOGGER.info("Using {} percent LLC routing for table {}", entry.getValue(), entry.getKey());
                _percentMap.put(entry.getKey(), entry.getValue());
            }
        } catch (Exception e) {
            LOGGER.warn("Could not parse get config for {}. Using no LLC routing", TABLE_KEY, e);
        }
    }

    @Override
    public boolean shouldUseLLCRouting(String realtimeTableName) {
        Integer percentToLLC = _percentMap.get(realtimeTableName);
        if (percentToLLC == null || percentToLLC == 0) {
            return false;
        }
        if (_random.nextInt(100) < percentToLLC) {
            return true;
        }
        return false;
    }
}