org.apache.kudu.mapreduce.tools.ImportCsvMapper.java Source code

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Here is the source code for org.apache.kudu.mapreduce.tools.ImportCsvMapper.java

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/**
 *
 * 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. See accompanying LICENSE file.
 */

package org.apache.kudu.mapreduce.tools;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Counter;
import org.apache.hadoop.mapreduce.Mapper;

import org.apache.kudu.ColumnSchema;
import org.apache.kudu.Schema;
import org.apache.kudu.annotations.InterfaceAudience;
import org.apache.kudu.annotations.InterfaceStability;
import org.apache.kudu.client.Bytes;
import org.apache.kudu.client.Insert;
import org.apache.kudu.client.KuduTable;
import org.apache.kudu.client.Operation;
import org.apache.kudu.client.PartialRow;
import org.apache.kudu.mapreduce.KuduTableMapReduceUtil;

/**
 * Mapper that ingests CSV lines and turns them into Kudu Inserts.
 */
@InterfaceAudience.Private
@InterfaceStability.Evolving
public class ImportCsvMapper extends Mapper<LongWritable, Text, NullWritable, Operation> {

    private static final NullWritable NULL_KEY = NullWritable.get();

    /** Column seperator */
    private String separator;

    /** Should skip bad lines */
    private boolean skipBadLines;
    private Counter badLineCount;

    private CsvParser parser;

    private KuduTable table;
    private Schema schema;

    /**
     * Handles initializing this class with objects specific to it (i.e., the parser).
     */
    @Override
    protected void setup(Context context) {
        Configuration conf = context.getConfiguration();

        this.separator = conf.get(ImportCsv.SEPARATOR_CONF_KEY);
        if (this.separator == null) {
            this.separator = ImportCsv.DEFAULT_SEPARATOR;
        }

        this.skipBadLines = conf.getBoolean(ImportCsv.SKIP_LINES_CONF_KEY, true);
        this.badLineCount = context.getCounter(ImportCsv.Counters.BAD_LINES);

        this.parser = new CsvParser(conf.get(ImportCsv.COLUMNS_NAMES_KEY), this.separator);

        this.table = KuduTableMapReduceUtil.getTableFromContext(context);
        this.schema = this.table.getSchema();
    }

    /**
     * Convert a line of CSV text into a Kudu Insert
     */
    @Override
    public void map(LongWritable offset, Text value, Context context) throws IOException {
        byte[] lineBytes = value.getBytes();

        try {
            CsvParser.ParsedLine parsed = this.parser.parse(lineBytes, value.getLength());

            Insert insert = this.table.newInsert();
            PartialRow row = insert.getRow();
            for (int i = 0; i < parsed.getColumnCount(); i++) {
                String colName = parsed.getColumnName(i);
                ColumnSchema col = this.schema.getColumn(colName);
                String colValue = Bytes.getString(parsed.getLineBytes(), parsed.getColumnOffset(i),
                        parsed.getColumnLength(i));
                switch (col.getType()) {
                case BOOL:
                    row.addBoolean(colName, Boolean.parseBoolean(colValue));
                    break;
                case INT8:
                    row.addByte(colName, Byte.parseByte(colValue));
                    break;
                case INT16:
                    row.addShort(colName, Short.parseShort(colValue));
                    break;
                case INT32:
                    row.addInt(colName, Integer.parseInt(colValue));
                    break;
                case INT64:
                    row.addLong(colName, Long.parseLong(colValue));
                    break;
                case STRING:
                    row.addString(colName, colValue);
                    break;
                case FLOAT:
                    row.addFloat(colName, Float.parseFloat(colValue));
                    break;
                case DOUBLE:
                    row.addDouble(colName, Double.parseDouble(colValue));
                    break;
                default:
                    throw new IllegalArgumentException("Type " + col.getType() + " not recognized");
                }
            }
            context.write(NULL_KEY, insert);
        } catch (CsvParser.BadCsvLineException badLine) {
            if (this.skipBadLines) {
                System.err.println("Bad line at offset: " + offset.get() + ":\n" + badLine.getMessage());
                this.badLineCount.increment(1);
                return;
            } else {
                throw new IOException("Failing task because of a bad line", badLine);
            }
        } catch (IllegalArgumentException e) {
            if (this.skipBadLines) {
                System.err.println("Bad line at offset: " + offset.get() + ":\n" + e.getMessage());
                this.badLineCount.increment(1);
                return;
            } else {
                throw new IOException("Failing task because of an illegal argument", e);
            }
        } catch (InterruptedException e) {
            throw new IOException("Failing task since it was interrupted", e);
        }
    }
}