/**
* 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.handler.extraction;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;
import java.util.Locale;
import org.apache.commons.io.IOUtils;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.common.params.UpdateParams;
import org.apache.solr.common.util.ContentStream;
import org.apache.solr.common.util.NamedList;
import org.apache.solr.handler.ContentStreamLoader;
import org.apache.solr.request.SolrQueryRequest;
import org.apache.solr.response.SolrQueryResponse;
import org.apache.solr.schema.IndexSchema;
import org.apache.solr.update.AddUpdateCommand;
import org.apache.solr.update.processor.UpdateRequestProcessor;
import org.apache.tika.config.TikaConfig;
import org.apache.tika.exception.TikaException;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.mime.MediaType;
import org.apache.tika.parser.AutoDetectParser;
import org.apache.tika.parser.ParseContext;
import org.apache.tika.parser.Parser;
import org.apache.tika.sax.XHTMLContentHandler;
import org.apache.tika.sax.xpath.Matcher;
import org.apache.tika.sax.xpath.MatchingContentHandler;
import org.apache.tika.sax.xpath.XPathParser;
import org.apache.tika.exception.TikaException;
import org.apache.xml.serialize.BaseMarkupSerializer;
import org.apache.xml.serialize.OutputFormat;
import org.apache.xml.serialize.TextSerializer;
import org.apache.xml.serialize.XMLSerializer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.apache.tika.mime.MediaType;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;
/**
* The class responsible for loading extracted content into Solr.
*
**/
public class ExtractingDocumentLoader extends ContentStreamLoader {
private static final Logger log = LoggerFactory.getLogger(ExtractingDocumentLoader.class);
/**
* Extract Only supported format
*/
public static final String TEXT_FORMAT = "text";
/**
* Extract Only supported format. Default
*/
public static final String XML_FORMAT = "xml";
/**
* XHTML XPath parser.
*/
private static final XPathParser PARSER =
new XPathParser("xhtml", XHTMLContentHandler.XHTML);
final IndexSchema schema;
final SolrParams params;
final UpdateRequestProcessor processor;
final boolean ignoreTikaException;
protected AutoDetectParser autoDetectParser;
private final AddUpdateCommand templateAdd;
protected TikaConfig config;
protected SolrContentHandlerFactory factory;
//protected Collection<String> dateFormats = DateUtil.DEFAULT_DATE_FORMATS;
public ExtractingDocumentLoader(SolrQueryRequest req, UpdateRequestProcessor processor,
TikaConfig config, SolrContentHandlerFactory factory) {
this.params = req.getParams();
schema = req.getSchema();
this.config = config;
this.processor = processor;
templateAdd = new AddUpdateCommand();
templateAdd.allowDups = false;
templateAdd.overwriteCommitted = true;
templateAdd.overwritePending = true;
if (params.getBool(UpdateParams.OVERWRITE, true)) {
templateAdd.allowDups = false;
templateAdd.overwriteCommitted = true;
templateAdd.overwritePending = true;
} else {
templateAdd.allowDups = true;
templateAdd.overwriteCommitted = false;
templateAdd.overwritePending = false;
}
//this is lightweight
autoDetectParser = new AutoDetectParser(config);
this.factory = factory;
ignoreTikaException = params.getBool(ExtractingParams.IGNORE_TIKA_EXCEPTION, false);
}
/**
* this must be MT safe... may be called concurrently from multiple threads.
*
* @param
* @param
*/
void doAdd(SolrContentHandler handler, AddUpdateCommand template)
throws IOException {
template.solrDoc = handler.newDocument();
processor.processAdd(template);
}
void addDoc(SolrContentHandler handler) throws IOException {
templateAdd.indexedId = null;
doAdd(handler, templateAdd);
}
/**
* @param req
* @param stream
* @throws java.io.IOException
*/
@Override
public void load(SolrQueryRequest req, SolrQueryResponse rsp, ContentStream stream) throws IOException {
errHeader = "ExtractingDocumentLoader: " + stream.getSourceInfo();
Parser parser = null;
String streamType = req.getParams().get(ExtractingParams.STREAM_TYPE, null);
if (streamType != null) {
//Cache? Parsers are lightweight to construct and thread-safe, so I'm told
MediaType mt = MediaType.parse(streamType.trim().toLowerCase());
parser = config.getParser(mt);
} else {
parser = autoDetectParser;
}
if (parser != null) {
Metadata metadata = new Metadata();
metadata.add(ExtractingMetadataConstants.STREAM_NAME, stream.getName());
metadata.add(ExtractingMetadataConstants.STREAM_SOURCE_INFO, stream.getSourceInfo());
metadata.add(ExtractingMetadataConstants.STREAM_SIZE, String.valueOf(stream.getSize()));
metadata.add(ExtractingMetadataConstants.STREAM_CONTENT_TYPE, stream.getContentType());
// If you specify the resource name (the filename, roughly) with this parameter,
// then Tika can make use of it in guessing the appropriate MIME type:
String resourceName = req.getParams().get(ExtractingParams.RESOURCE_NAME, null);
if (resourceName != null) {
metadata.add(Metadata.RESOURCE_NAME_KEY, resourceName);
}
SolrContentHandler handler = factory.createSolrContentHandler(metadata, params, schema);
InputStream inputStream = null;
try {
inputStream = stream.getStream();
String xpathExpr = params.get(ExtractingParams.XPATH_EXPRESSION);
boolean extractOnly = params.getBool(ExtractingParams.EXTRACT_ONLY, false);
ContentHandler parsingHandler = handler;
StringWriter writer = null;
BaseMarkupSerializer serializer = null;
if (extractOnly == true) {
String extractFormat = params.get(ExtractingParams.EXTRACT_FORMAT, "xml");
writer = new StringWriter();
if (extractFormat.equals(TEXT_FORMAT)) {
serializer = new TextSerializer();
serializer.setOutputCharStream(writer);
serializer.setOutputFormat(new OutputFormat("Text", "UTF-8", true));
} else {
serializer = new XMLSerializer(writer, new OutputFormat("XML", "UTF-8", true));
}
if (xpathExpr != null) {
Matcher matcher =
PARSER.parse(xpathExpr);
serializer.startDocument();//The MatchingContentHandler does not invoke startDocument. See http://tika.markmail.org/message/kknu3hw7argwiqin
parsingHandler = new MatchingContentHandler(serializer, matcher);
} else {
parsingHandler = serializer;
}
} else if (xpathExpr != null) {
Matcher matcher =
PARSER.parse(xpathExpr);
parsingHandler = new MatchingContentHandler(handler, matcher);
} //else leave it as is
try{
//potentially use a wrapper handler for parsing, but we still need the SolrContentHandler for getting the document.
ParseContext context = new ParseContext();//TODO: should we design a way to pass in parse context?
parser.parse(inputStream, parsingHandler, metadata, context);
} catch (TikaException e) {
if(ignoreTikaException)
log.warn(new StringBuilder("skip extracting text due to ").append(e.getLocalizedMessage())
.append(". metadata=").append(metadata.toString()).toString());
else
throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, e);
}
if (extractOnly == false) {
addDoc(handler);
} else {
//serializer is not null, so we need to call endDoc on it if using xpath
if (xpathExpr != null){
serializer.endDocument();
}
rsp.add(stream.getName(), writer.toString());
writer.close();
String[] names = metadata.names();
NamedList metadataNL = new NamedList();
for (int i = 0; i < names.length; i++) {
String[] vals = metadata.getValues(names[i]);
metadataNL.add(names[i], vals);
}
rsp.add(stream.getName() + "_metadata", metadataNL);
}
} catch (SAXException e) {
throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, e);
} finally {
IOUtils.closeQuietly(inputStream);
}
} else {
throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "Stream type of " + streamType + " didn't match any known parsers. Please supply the " + ExtractingParams.STREAM_TYPE + " parameter.");
}
}
}