com.datatorrent.contrib.couchbase.AbstractCouchBaseInputOperator.java Source code

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Here is the source code for com.datatorrent.contrib.couchbase.AbstractCouchBaseInputOperator.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 com.datatorrent.contrib.couchbase;

import java.io.IOException;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;

import com.couchbase.client.CouchbaseClient;
import com.couchbase.client.vbucket.config.Config;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.Lists;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.datatorrent.lib.db.AbstractStoreInputOperator;

import com.datatorrent.api.Context;
import com.datatorrent.api.DefaultPartition;
import com.datatorrent.api.Partitioner;

import com.datatorrent.lib.util.KryoCloneUtils;
import com.datatorrent.netlet.util.DTThrowable;

/**
 * AbstractCouchBaseInputOperator which extends AbstractStoreInputOperator.
 * Classes extending from this operator should implement the abstract functionality of getTuple and getKeys.
 *
 * @since 2.0.0
 */
public abstract class AbstractCouchBaseInputOperator<T> extends AbstractStoreInputOperator<T, CouchBaseStore>
        implements Partitioner<AbstractCouchBaseInputOperator<T>> {
    private static final Logger logger = LoggerFactory.getLogger(AbstractCouchBaseInputOperator.class);
    protected transient CouchbaseClient clientPartition = null;

    private int serverIndex;

    protected transient Config conf;

    // URL specific to a server.
    protected String serverURIString;

    public String getServerURIString() {
        return serverURIString;
    }

    @VisibleForTesting
    public void setServerURIString(String serverURIString) {
        this.serverURIString = serverURIString;
    }

    public int getServerIndex() {
        return serverIndex;
    }

    public void setServerIndex(int serverIndex) {
        this.serverIndex = serverIndex;
    }

    public AbstractCouchBaseInputOperator() {
        store = new CouchBaseStore();
    }

    @Override
    public void setup(Context.OperatorContext context) {
        if (clientPartition == null) {
            if (conf == null) {
                conf = store.getConf();
            }
            try {
                clientPartition = store.connectServer(serverURIString);
            } catch (IOException ex) {
                DTThrowable.rethrow(ex);
            }
        }
    }

    @Override
    public void teardown() {
        if (clientPartition != null) {
            clientPartition.shutdown(store.shutdownTimeout, TimeUnit.SECONDS);
        }
        super.teardown();
    }

    @Override
    public void emitTuples() {
        List<String> keys = getKeys();
        Object result = null;
        for (String key : keys) {
            int master = conf.getMaster(conf.getVbucketByKey(key));
            if (master == getServerIndex()) {
                result = clientPartition.get(key);
            }
        }

        if (result != null) {
            T tuple = getTuple(result);
            outputPort.emit(tuple);
        }
    }

    public abstract T getTuple(Object object);

    public abstract List<String> getKeys();

    @Override
    public void partitioned(Map<Integer, Partition<AbstractCouchBaseInputOperator<T>>> partitions) {

    }

    @Override
    public Collection<Partition<AbstractCouchBaseInputOperator<T>>> definePartitions(
            Collection<Partition<AbstractCouchBaseInputOperator<T>>> partitions,
            PartitioningContext incrementalCapacity) {
        conf = store.getConf();
        int numPartitions = conf.getServers().size();
        List<String> list = conf.getServers();
        Collection<Partition<AbstractCouchBaseInputOperator<T>>> newPartitions = Lists
                .newArrayListWithExpectedSize(numPartitions);
        KryoCloneUtils<AbstractCouchBaseInputOperator<T>> cloneUtils = KryoCloneUtils.createCloneUtils(this);
        for (int i = 0; i < numPartitions; i++) {
            AbstractCouchBaseInputOperator<T> oper = cloneUtils.getClone();
            oper.setServerIndex(i);
            oper.setServerURIString(list.get(i));
            logger.debug("oper {} urlstring is {}", i, oper.getServerURIString());
            newPartitions.add(new DefaultPartition<>(oper));
        }

        return newPartitions;

    }

}