org.apache.solr.update.processor.ClassificationUpdateProcessor Maven / Gradle / Ivy
/*
* 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 org.apache.solr.update.processor;
import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.classification.ClassificationResult;
import org.apache.lucene.classification.document.DocumentClassifier;
import org.apache.lucene.classification.document.KNearestNeighborDocumentClassifier;
import org.apache.lucene.classification.document.SimpleNaiveBayesDocumentClassifier;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.util.BytesRef;
import org.apache.solr.common.SolrInputDocument;
import org.apache.solr.schema.IndexSchema;
import org.apache.solr.schema.SchemaField;
import org.apache.solr.update.AddUpdateCommand;
import org.apache.solr.update.processor.ClassificationUpdateProcessorFactory.Algorithm;
/**
* This Class is a Request Update Processor to classify the document in input and add a field
* containing the class to the Document.
* It uses the Lucene Document Classification module, see {@link DocumentClassifier}.
*/
class ClassificationUpdateProcessor
extends UpdateRequestProcessor {
private final String trainingClassField;
private final String predictedClassField;
private final int maxOutputClasses;
private DocumentClassifier classifier;
/**
* Sole constructor
*
* @param classificationParams classification advanced params
* @param next next update processor in the chain
* @param indexReader index reader
* @param schema schema
*/
public ClassificationUpdateProcessor(ClassificationUpdateProcessorParams classificationParams, UpdateRequestProcessor next, IndexReader indexReader, IndexSchema schema) {
super(next);
this.trainingClassField = classificationParams.getTrainingClassField();
this.predictedClassField = classificationParams.getPredictedClassField();
this.maxOutputClasses = classificationParams.getMaxPredictedClasses();
String[] inputFieldNamesWithBoost = classificationParams.getInputFieldNames();
Algorithm classificationAlgorithm = classificationParams.getAlgorithm();
Map field2analyzer = new HashMap<>();
String[] inputFieldNames = this.removeBoost(inputFieldNamesWithBoost);
for (String fieldName : inputFieldNames) {
SchemaField fieldFromSolrSchema = schema.getField(fieldName);
Analyzer indexAnalyzer = fieldFromSolrSchema.getType().getQueryAnalyzer();
field2analyzer.put(fieldName, indexAnalyzer);
}
switch (classificationAlgorithm) {
case KNN:
classifier = new KNearestNeighborDocumentClassifier(indexReader, null, classificationParams.getTrainingFilterQuery(), classificationParams.getK(), classificationParams.getMinDf(), classificationParams.getMinTf(), trainingClassField, field2analyzer, inputFieldNamesWithBoost);
break;
case BAYES:
classifier = new SimpleNaiveBayesDocumentClassifier(indexReader, null, trainingClassField, field2analyzer, inputFieldNamesWithBoost);
break;
}
}
private String[] removeBoost(String[] inputFieldNamesWithBoost) {
String[] inputFieldNames = new String[inputFieldNamesWithBoost.length];
for (int i = 0; i < inputFieldNamesWithBoost.length; i++) {
String singleFieldNameWithBoost = inputFieldNamesWithBoost[i];
String[] fieldName2boost = singleFieldNameWithBoost.split("\\^");
inputFieldNames[i] = fieldName2boost[0];
}
return inputFieldNames;
}
/**
* @param cmd the update command in input containing the Document to classify
* @throws IOException If there is a low-level I/O error
*/
@Override
public void processAdd(AddUpdateCommand cmd)
throws IOException {
SolrInputDocument doc = cmd.getSolrInputDocument();
Document luceneDocument = cmd.getLuceneDocument();
String assignedClass;
Object documentClass = doc.getFieldValue(trainingClassField);
if (documentClass == null) {
List> assignedClassifications = classifier.getClasses(luceneDocument, maxOutputClasses);
if (assignedClassifications != null) {
for (ClassificationResult singleClassification : assignedClassifications) {
assignedClass = singleClassification.getAssignedClass().utf8ToString();
doc.addField(predictedClassField, assignedClass);
}
}
}
super.processAdd(cmd);
}
}