org.apache.hive.spark.counter.SparkCounters.java Source code

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Here is the source code for org.apache.hive.spark.counter.SparkCounters.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
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * 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.hive.spark.counter;

import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.spark.api.java.JavaSparkContext;

/**
 * SparkCounters is used to collect Hive operator metric through Spark accumulator. There are few
 * limitation of Spark accumulator, like:
 * 1. accumulator should be created at Spark context side.
 * 2. Spark tasks can only increment metric count.
 * 3. User can only get accumulator value at Spark context side.
 * These Spark Counter API is designed to fit into Hive requirement, while with several access
 * restriction due to Spark accumulator previous mentioned:
 * 1. Counter should be created on driver side if it would be accessed in task.
 * 2. increment could only be invoked task side.
 * 3. Hive could only get Counter value at driver side.
 */
public class SparkCounters implements Serializable {
    private static final long serialVersionUID = 1L;

    private static final Log LOG = LogFactory.getLog(SparkCounters.class);

    private Map<String, SparkCounterGroup> sparkCounterGroups;

    private final transient JavaSparkContext javaSparkContext;

    private SparkCounters() {
        this(null);
    }

    public SparkCounters(JavaSparkContext javaSparkContext) {
        this.javaSparkContext = javaSparkContext;
        this.sparkCounterGroups = new HashMap<String, SparkCounterGroup>();
    }

    public void createCounter(Enum<?> key) {
        createCounter(key.getDeclaringClass().getName(), key.name());
    }

    public void createCounter(String groupName, Enum<?> key) {
        createCounter(groupName, key.name(), 0L);
    }

    public void createCounter(String groupName, String counterName) {
        createCounter(groupName, counterName, 0L);
    }

    public void createCounter(String groupName, String counterName, long initValue) {
        getGroup(groupName).createCounter(counterName, initValue);
    }

    public void increment(Enum<?> key, long incrValue) {
        increment(key.getDeclaringClass().getName(), key.name(), incrValue);
    }

    public void increment(String groupName, String counterName, long value) {
        SparkCounter counter = getGroup(groupName).getCounter(counterName);
        if (counter == null) {
            LOG.error(String.format("counter[%s, %s] has not initialized before.", groupName, counterName));
        } else {
            counter.increment(value);
        }
    }

    public long getValue(String groupName, String counterName) {
        SparkCounter counter = getGroup(groupName).getCounter(counterName);
        if (counter == null) {
            LOG.error(String.format("counter[%s, %s] has not initialized before.", groupName, counterName));
            return 0;
        } else {
            return counter.getValue();
        }
    }

    public SparkCounter getCounter(String groupName, String counterName) {
        return getGroup(groupName).getCounter(counterName);
    }

    public SparkCounter getCounter(Enum<?> key) {
        return getCounter(key.getDeclaringClass().getName(), key.name());
    }

    private SparkCounterGroup getGroup(String groupName) {
        SparkCounterGroup group = sparkCounterGroups.get(groupName);
        if (group == null) {
            group = new SparkCounterGroup(groupName, groupName, javaSparkContext);
            sparkCounterGroups.put(groupName, group);
        }
        return group;
    }

    public Map<String, SparkCounterGroup> getSparkCounterGroups() {
        return sparkCounterGroups;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        Map<String, SparkCounterGroup> groups = getSparkCounterGroups();
        if (groups != null) {
            for (Map.Entry<String, SparkCounterGroup> groupEntry : groups.entrySet()) {
                String groupName = groupEntry.getKey();
                SparkCounterGroup group = groupEntry.getValue();
                sb.append(groupName).append("\n");
                Map<String, SparkCounter> counters = group.getSparkCounters();
                for (Map.Entry<String, SparkCounter> counterEntry : counters.entrySet()) {
                    String counterName = counterEntry.getKey();
                    SparkCounter counter = counterEntry.getValue();
                    sb.append("\t").append(counterName).append(": ").append(counter.getValue()).append("\n");
                }
            }
        }

        return sb.toString();
    }

    /**
     * Create a snapshot of the current counters to send back to the client. This copies the values
     * of all current counters into a new SparkCounters instance that cannot be used to update the
     * counters, but will serialize cleanly when sent back to the RSC client.
     */
    public SparkCounters snapshot() {
        SparkCounters snapshot = new SparkCounters();
        for (SparkCounterGroup group : sparkCounterGroups.values()) {
            SparkCounterGroup groupSnapshot = group.snapshot();
            snapshot.sparkCounterGroups.put(groupSnapshot.getGroupName(), groupSnapshot);
        }
        return snapshot;
    }

}