You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
188 lines
7.9 KiB
188 lines
7.9 KiB
// AbstractCompressorParser.java
|
|
// ---------------------------
|
|
// Copyright 2018 by luccioman; https://github.com/luccioman
|
|
//
|
|
// This is a part of YaCy, a peer-to-peer based web search engine
|
|
//
|
|
// LICENSE
|
|
//
|
|
// This program is free software; you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation; either version 2 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// This program is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with this program; if not, write to the Free Software
|
|
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
|
|
package net.yacy.document.parser;
|
|
|
|
import java.io.IOException;
|
|
import java.io.InputStream;
|
|
import java.net.MalformedURLException;
|
|
import java.util.Date;
|
|
import java.util.Set;
|
|
|
|
import org.apache.commons.compress.compressors.CompressorInputStream;
|
|
|
|
import net.yacy.cora.document.id.DigestURL;
|
|
import net.yacy.cora.document.id.MultiProtocolURL;
|
|
import net.yacy.document.AbstractParser;
|
|
import net.yacy.document.Document;
|
|
import net.yacy.document.Parser;
|
|
import net.yacy.document.TextParser;
|
|
import net.yacy.document.VocabularyScraper;
|
|
|
|
/**
|
|
* Base class for parsing compressed files relying on Apache commons-compress
|
|
* tools.
|
|
*/
|
|
public abstract class AbstractCompressorParser extends AbstractParser implements Parser {
|
|
|
|
/** Crawl depth applied when parsing internal compressed content */
|
|
protected static final int DEFAULT_DEPTH = 999;
|
|
|
|
/**
|
|
* @param name the human readable name of the parser
|
|
*/
|
|
public AbstractCompressorParser(final String name) {
|
|
super(name);
|
|
}
|
|
|
|
/**
|
|
* @param source an open input stream on a compressed source
|
|
* @return a sub class of CompressorInputStream capable of uncompressing the source
|
|
* on the fly
|
|
* @throws IOException when an error occurred when trying to open the compressed
|
|
* stream
|
|
*/
|
|
protected abstract CompressorInputStream createDecompressStream(final InputStream source) throws IOException;
|
|
|
|
/**
|
|
* Maps the given name of a compressed file to the name that the
|
|
* file should have after uncompression. For example, for "file.txt.xz", "file.txt" is returned.
|
|
*
|
|
* @param filename name of a compressed file
|
|
* @return name of the corresponding uncompressed file
|
|
*/
|
|
protected abstract String getUncompressedFilename(final String filename);
|
|
|
|
@Override
|
|
public Document[] parse(final DigestURL location, final String mimeType, final String charset,
|
|
final Set<String> ignoreClassNames, final VocabularyScraper scraper, final int timezoneOffset,
|
|
final InputStream source) throws Parser.Failure, InterruptedException {
|
|
|
|
return parseWithLimits(location, mimeType, charset, scraper, timezoneOffset, source, Integer.MAX_VALUE,
|
|
Long.MAX_VALUE);
|
|
}
|
|
|
|
@Override
|
|
public Document[] parseWithLimits(final DigestURL location, final String mimeType, final String charset,
|
|
final Set<String> ignoreClassNames, final VocabularyScraper scraper, final int timezoneOffset,
|
|
final InputStream source, final int maxLinks, final long maxBytes) throws Parser.Failure {
|
|
Document maindoc;
|
|
final CompressorInputStream compressedInStream;
|
|
try {
|
|
compressedInStream = createDecompressStream(source);
|
|
} catch (final IOException | RuntimeException e) {
|
|
throw new Parser.Failure("Unexpected error while parsing compressed file. " + e.getMessage(), location);
|
|
}
|
|
|
|
try {
|
|
// create maindoc for this archive, register with supplied url & mime
|
|
maindoc = AbstractCompressorParser.createMainDocument(location, mimeType, charset, this);
|
|
|
|
final Document[] docs = this.parseCompressedInputStream(location, null, ignoreClassNames, timezoneOffset,
|
|
AbstractCompressorParser.DEFAULT_DEPTH, compressedInStream, maxLinks, maxBytes);
|
|
if (docs != null) {
|
|
maindoc.addSubDocuments(docs);
|
|
if (docs.length > 0 && docs[0].isPartiallyParsed()) {
|
|
maindoc.setPartiallyParsed(true);
|
|
}
|
|
}
|
|
} catch (final Parser.Failure e) {
|
|
throw e;
|
|
} catch (final IOException | RuntimeException e) {
|
|
throw new Parser.Failure("Unexpected error while parsing compressed file. " + e.getMessage(), location);
|
|
}
|
|
return new Document[] { maindoc };
|
|
}
|
|
|
|
/**
|
|
* Create the main parsed document for the compressed document at the given URL
|
|
* and Media type
|
|
*
|
|
* @param location the parsed resource URL
|
|
* @param mimeType the media type of the resource
|
|
* @param charset the charset name if known
|
|
* @param parser an instance of CompressorParser that is registered as the
|
|
* parser origin of the document
|
|
* @return a Document instance
|
|
*/
|
|
protected static Document createMainDocument(final DigestURL location, final String mimeType, final String charset,
|
|
final AbstractCompressorParser parser) {
|
|
final String filename = location.getFileName();
|
|
return new Document(location, mimeType, charset, parser, null, null,
|
|
AbstractParser
|
|
.singleList(filename.isEmpty() ? location.toTokens() : MultiProtocolURL.unescape(filename)), // title
|
|
null, null, null, null, 0.0d, 0.0d, (Object) null, null, null, null, false, new Date());
|
|
}
|
|
|
|
/**
|
|
* Parse content in an open stream uncompressing on the fly a compressed
|
|
* resource.
|
|
*
|
|
* @param location the URL of the compressed resource
|
|
* @param charset the charset name if known
|
|
* @param ignoreClassNames an eventual set of CSS class names whose matching
|
|
* html elements content should be ignored
|
|
* @param timezoneOffset the local time zone offset
|
|
* @param compressedInStream an open stream uncompressing on the fly the
|
|
* compressed content
|
|
* @param maxLinks the maximum total number of links to parse and add
|
|
* to the result documents
|
|
* @param maxBytes the maximum number of content bytes to process
|
|
* @return a list of documents that result from parsing the source, with empty
|
|
* or null text.
|
|
* @throws Parser.Failure when the parser processing failed
|
|
*/
|
|
protected Document[] parseCompressedInputStream(final DigestURL location, final String charset,
|
|
final Set<String> ignoreClassNames, final int timezoneOffset, final int depth,
|
|
final CompressorInputStream compressedInStream, final int maxLinks, final long maxBytes) throws Failure {
|
|
final String compressedFileName = location.getFileName();
|
|
final String contentfilename = getUncompressedFilename(compressedFileName);
|
|
final String mime = TextParser.mimeOf(MultiProtocolURL.getFileExtension(contentfilename));
|
|
try {
|
|
/*
|
|
* Use the uncompressed file name for sub parsers to not unnecessarily use again
|
|
* this same uncompressing parser
|
|
*/
|
|
final String locationPath = location.getPath();
|
|
final String contentPath = locationPath.substring(0, locationPath.length() - compressedFileName.length())
|
|
+ contentfilename;
|
|
final DigestURL contentLocation = new DigestURL(location.getProtocol(), location.getHost(),
|
|
location.getPort(), contentPath);
|
|
|
|
/*
|
|
* Rely on the supporting parsers to respect the maxLinks and maxBytes limits on
|
|
* compressed content
|
|
*/
|
|
return TextParser.parseWithLimits(contentLocation, mime, charset, ignoreClassNames, timezoneOffset, depth,
|
|
-1, compressedInStream, maxLinks, maxBytes);
|
|
} catch (final MalformedURLException e) {
|
|
throw new Parser.Failure("Unexpected error while parsing compressed file. " + e.getMessage(), location);
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public boolean isParseWithLimitsSupported() {
|
|
return true;
|
|
}
|
|
|
|
}
|