org.apache.tika.parser.mail.RFC822Parser 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.tika.parser.mail;
import java.io.IOException;
import java.io.InputStream;
import java.util.Collections;
import java.util.Set;
import org.apache.james.mime4j.MimeException;
import org.apache.james.mime4j.message.DefaultBodyDescriptorBuilder;
import org.apache.james.mime4j.parser.MimeStreamParser;
import org.apache.james.mime4j.stream.MimeConfig;
import org.apache.tika.config.Field;
import org.apache.tika.detect.Detector;
import org.apache.tika.exception.TikaException;
import org.apache.tika.extractor.EmbeddedDocumentUtil;
import org.apache.tika.io.TikaInputStream;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.mime.MediaType;
import org.apache.tika.parser.AbstractParser;
import org.apache.tika.parser.ParseContext;
import org.apache.tika.sax.XHTMLContentHandler;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
/**
* Uses apache-mime4j to parse emails. Each part is treated with the
* corresponding parser and displayed within elements.
*
* A {@link MimeConfig} object can be passed in the parsing context
* to better control the parsing process.
*
* @author [email protected]
*/
public class RFC822Parser extends AbstractParser {
/**
* Serial version UID
*/
private static final long serialVersionUID = -5504243905998074168L;
private static final Set SUPPORTED_TYPES = Collections
.singleton(MediaType.parse("message/rfc822"));
//rely on the detector to be thread-safe
//built lazily and then reused
private Detector detector;
@Field
private boolean extractAllAlternatives = false;
public Set getSupportedTypes(ParseContext context) {
return SUPPORTED_TYPES;
}
public void parse(InputStream stream, ContentHandler handler,
Metadata metadata, ParseContext context) throws IOException,
SAXException, TikaException {
// Get the mime4j configuration, or use a default one
MimeConfig config = new MimeConfig.Builder()
.setMaxLineLen(100000)
.setMaxHeaderLen(100000)
.build();
config = context.get(MimeConfig.class, config);
Detector localDetector = context.get(Detector.class);
if (localDetector == null) {
//lazily load this if necessary
if (detector == null) {
EmbeddedDocumentUtil embeddedDocumentUtil = new EmbeddedDocumentUtil(context);
detector = embeddedDocumentUtil.getDetector();
}
localDetector = detector;
}
MimeStreamParser parser = new MimeStreamParser(config, null, new DefaultBodyDescriptorBuilder());
XHTMLContentHandler xhtml = new XHTMLContentHandler(handler, metadata);
MailContentHandler mch = new MailContentHandler(
xhtml, localDetector, metadata, context, config.isStrictParsing(),
extractAllAlternatives);
parser.setContentHandler(mch);
parser.setContentDecoding(true);
TikaInputStream tstream = TikaInputStream.get(stream);
try {
parser.parse(tstream);
} catch (IOException e) {
tstream.throwIfCauseOf(e);
throw new TikaException("Failed to parse an email message", e);
} catch (MimeException e) {
// Unwrap the exception in case it was not thrown by mime4j
Throwable cause = e.getCause();
if (cause instanceof TikaException) {
throw (TikaException) cause;
} else if (cause instanceof SAXException) {
throw (SAXException) cause;
} else {
throw new TikaException("Failed to parse an email message", e);
}
}
}
/**
* Until version 1.17, Tika handled all body parts as embedded objects (see TIKA-2478).
* In 1.17, we modified the parser to select only the best alternative body
* parts for multipart/alternative sections, and we inline the content
* as we do for .msg files.
*
* The legacy behavior can be set by setting {@link #extractAllAlternatives}
* to true. As of 1.17, the default value is false
*
* @param extractAllAlternatives whether or not to extract all alternative parts
* @since 1.17
*/
public void setExtractAllAlternatives(boolean extractAllAlternatives) {
this.extractAllAlternatives = extractAllAlternatives;
}
}