com.marklogic.mapreduce.PropertyOutputFormat Maven / Gradle / Ivy
/*
* Copyright (c) 2020 MarkLogic Corporation
*
* 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.marklogic.mapreduce;
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.DefaultStringifier;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import com.marklogic.mapreduce.utilities.InternalUtilities;
import com.marklogic.mapreduce.utilities.TextArrayWritable;
import com.marklogic.xcc.ContentSource;
/**
* MarkLogicOutputFormat for Document Property.
*
*
* Use this class to store MapReduce results as properties on documents
* in a MarkLogic database. This class expects output key-value pairs
* where the key is a {@link DocumentURI} and the value is a {@link MarkLogicNode}
* describing the property to be added to the document at the key URI.
*
*
* Control whether the inserted property replaces or adds to existing
* document properties by setting the configuration property
* {@link MarkLogicConstants#DEFAULT_PROPERTY_OPERATION_TYPE output.property.optype}.
* By default, any existing properties are replaced with the new one.
*
*
* By default, properties are only created by documents that exist in the
* database. Set the configuration property
* {@link MarkLogicConstants#OUTPUT_PROPERTY_ALWAYS_CREATE output.property.alwayscreate}
* to true to create properties even if the target document does not exist.
*
*
* @see PropertyOpType
*
* @author jchen
*/
public class PropertyOutputFormat
extends MarkLogicOutputFormat {
public static final Log LOG =
LogFactory.getLog(PropertyOutputFormat.class);
@Override
public RecordWriter getRecordWriter(
TaskAttemptContext context) throws IOException, InterruptedException {
Configuration conf = context.getConfiguration();
TextArrayWritable hosts = getHosts(conf);
String host = InternalUtilities.getHost(hosts);
return new PropertyWriter(conf, host);
}
@Override
public void checkOutputSpecs(
Configuration conf, ContentSource cs, JobContext context)
throws IOException {
// warn against unsupported configuration
if (conf.get(BATCH_SIZE) != null) {
LOG.warn("Config entry for " +
"\"mapreduce.marklogic.output.batchsize\" is not " +
"supported for " + this.getClass().getName() +
" and will be ignored.");
}
// store hosts into config system
DefaultStringifier.store(conf, queryHosts(cs), OUTPUT_FOREST_HOST);
}
}