org.schedoscope.export.ftp.FtpExportCSVMapper.java Source code

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Here is the source code for org.schedoscope.export.ftp.FtpExportCSVMapper.java

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/**
 * Copyright 2016 Otto (GmbH & Co KG)
 * <p>
 * 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
 * <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.schedoscope.export.ftp;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.TaskCounter;
import org.apache.hive.hcatalog.data.HCatRecord;
import org.apache.hive.hcatalog.data.schema.HCatSchema;
import org.apache.hive.hcatalog.mapreduce.HCatInputFormat;
import org.schedoscope.export.BaseExportJob;
import org.schedoscope.export.utils.HCatRecordJsonSerializer;
import org.schedoscope.export.utils.HCatUtils;
import org.schedoscope.export.writables.TextPairArrayWritable;
import org.schedoscope.export.writables.TextPairWritable;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;

/**
 * A mapper that reads data from Hive via HCatalog and emits a TextPairArrayWritable.
 */
public class FtpExportCSVMapper
        extends Mapper<WritableComparable<?>, HCatRecord, LongWritable, TextPairArrayWritable> {

    private Configuration conf;

    private HCatSchema inputSchema;

    private HCatRecordJsonSerializer serializer;

    private Set<String> anonFields;

    private String salt;

    @Override
    protected void setup(Context context) throws IOException, InterruptedException {

        super.setup(context);
        conf = context.getConfiguration();

        inputSchema = HCatInputFormat.getTableSchema(conf);

        serializer = new HCatRecordJsonSerializer(conf, inputSchema);

        anonFields = ImmutableSet.copyOf(conf.getStrings(BaseExportJob.EXPORT_ANON_FIELDS, new String[0]));

        salt = conf.get(BaseExportJob.EXPORT_ANON_SALT, "");
    }

    @Override
    protected void map(WritableComparable<?> key, HCatRecord value, Context context)
            throws IOException, InterruptedException {

        List<TextPairWritable> items = new ArrayList<TextPairWritable>();

        for (String f : inputSchema.getFieldNames()) {

            String fieldValue = "";

            Object obj = value.get(f, inputSchema);
            if (obj != null) {

                if (inputSchema.get(f).isComplex()) {
                    fieldValue = serializer.getFieldAsJson(value, f);
                } else {
                    fieldValue = obj.toString();
                    fieldValue = HCatUtils.getHashValueIfInList(f, fieldValue, anonFields, salt);
                }
            }

            TextPairWritable item = new TextPairWritable(f, fieldValue);
            items.add(item);
        }

        TextPairArrayWritable record = new TextPairArrayWritable(Iterables.toArray(items, TextPairWritable.class));

        LongWritable localKey = new LongWritable(context.getCounter(TaskCounter.MAP_INPUT_RECORDS).getValue());
        context.write(localKey, record);
    }
}