Current File : //proc/309157/root/home/waritko/yacy/source/net/yacy/document/parser/gzipParser.java
//gzipParser.java
//------------------------
//part of YaCy
//(C) by Michael Peter Christen; mc@yacy.net
//first published on http://www.anomic.de
//Frankfurt, Germany, 2005
//
//this file is contributed by Martin Thelian
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
//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.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.util.Date;
import java.util.Set;
import java.util.zip.GZIPInputStream;
import org.apache.commons.compress.compressors.gzip.GzipUtils;
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;
import net.yacy.kelondro.util.FileUtils;
/**
* Parses a gz archive.
* Unzips and parses the content and adds it to the created main document
*/
public class gzipParser extends AbstractParser implements Parser {
private static final int DEFAULT_DEPTH = 999;
public gzipParser() {
super("GNU Zip Compressed Archive Parser");
this.SUPPORTED_EXTENSIONS.add("gz");
this.SUPPORTED_EXTENSIONS.add("tgz");
this.SUPPORTED_MIME_TYPES.add("application/x-gzip");
this.SUPPORTED_MIME_TYPES.add("application/gzip");
this.SUPPORTED_MIME_TYPES.add("application/x-gunzip");
this.SUPPORTED_MIME_TYPES.add("application/gzipped");
this.SUPPORTED_MIME_TYPES.add("application/gzip-compressed");
this.SUPPORTED_MIME_TYPES.add("gzip/document");
}
@Override
public Document[] parse(
final DigestURL location,
final String mimeType,
final String charset,
Set<String> ignore_class_name,
final VocabularyScraper scraper,
final int timezoneOffset,
final InputStream source) throws Parser.Failure, InterruptedException {
File tempFile = null;
Document maindoc = null;
GZIPInputStream zippedContent = null;
FileOutputStream out = null;
try {
zippedContent = new GZIPInputStream(source);
} catch(IOException e) {
/* Use a GZIPOpeningStreamException to signal the caller the error occurred directly on stream opening
* and eventually apply special error handling */
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(), location,
new GZIPOpeningStreamException());
}
try {
int read = 0;
final byte[] data = new byte[1024];
tempFile = File.createTempFile("gunzip","tmp");
// creating a temp file to store the uncompressed data
out = new FileOutputStream(tempFile);
// reading gzip file and store it uncompressed
while ((read = zippedContent.read(data, 0, 1024)) != -1) {
out.write(data, 0, read);
}
} catch(Exception e) {
if (tempFile != null) {
FileUtils.deletedelete(tempFile);
}
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(), location);
} finally {
if(zippedContent != null) {
try {
zippedContent.close();
} catch (IOException ignored) {
log.warn("Could not close gzip input stream");
}
}
if(out != null) {
try {
out.close();
} catch (IOException e) {
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(), location);
}
}
}
try {
maindoc = createMainDocument(location, mimeType, charset, this);
// creating a new parser class to parse the unzipped content
final String contentfilename = GzipUtils.getUncompressedFilename(location.getFileName());
final String mime = TextParser.mimeOf(MultiProtocolURL.getFileExtension(contentfilename));
Document[] docs = TextParser.parseSource(location, mime, null, ignore_class_name, scraper, timezoneOffset, DEFAULT_DEPTH, tempFile);
if (docs != null) maindoc.addSubDocuments(docs);
} catch (final Exception e) {
if (e instanceof InterruptedException) throw (InterruptedException) e;
if (e instanceof Parser.Failure) throw (Parser.Failure) e;
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(),location);
} finally {
if (tempFile != null) FileUtils.deletedelete(tempFile);
}
return maindoc == null ? null : new Document[]{maindoc};
}
/**
* Create the main parsed document for this gzip container, register with supplied url & mime type
* @param location the parsed resource URL
* @param mimeType the media type of the resource
* @param charset the charset name if known
* @param an instance of gzipParser that is registered as the parser origin of the document
* @return a Document instance
*/
public static Document createMainDocument(final DigestURL location, final String mimeType, final String charset, final gzipParser parser) {
final String filename = location.getFileName();
Document maindoc = 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());
return maindoc;
}
/**
* Parse content in an open stream uncompressing on the fly a gzipped resource.
* @param location the URL of the gzipped resource
* @param charset the charset name if known
* @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
*/
public Document[] parseCompressedInputStream(final DigestURL location, final String charset, final int timezoneOffset, final int depth,
final InputStream compressedInStream, final int maxLinks, final long maxBytes) throws Failure {
// creating a new parser class to parse the unzipped content
final String compressedFileName = location.getFileName();
final String contentfilename = GzipUtils.getUncompressedFilename(compressedFileName);
final String mime = TextParser.mimeOf(MultiProtocolURL.getFileExtension(contentfilename));
try {
/* Use the uncompressed file name for sub parsers to not unnecessarily use again the gzipparser */
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, timezoneOffset, depth, -1, compressedInStream, maxLinks, maxBytes);
} catch (MalformedURLException e) {
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(), location);
}
}
@Override
public boolean isParseWithLimitsSupported() {
return true;
}
@Override
public Document[] parseWithLimits(final DigestURL location, final String mimeType, final String charset, final VocabularyScraper scraper,
final int timezoneOffset, final InputStream source, final int maxLinks, final long maxBytes)
throws Parser.Failure {
Document maindoc = null;
GZIPInputStream zippedContent = null;
try {
/* Only use in-memory stream here (no temporary file) : the parsers
* matching compressed content are expected to handle properly the maxBytes limit and terminate
* before an eventual OutOfMemory occurs */
zippedContent = new GZIPInputStream(source);
} catch(IOException e) {
/* Use a GZIPOpeningStreamException to signal the caller the error occurred directly on stream opening
* and eventually apply special error handling */
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(), location,
new GZIPOpeningStreamException());
}
try {
maindoc = createMainDocument(location, mimeType, charset, this);
Document[] docs = parseCompressedInputStream(location, charset, timezoneOffset, DEFAULT_DEPTH, zippedContent, maxLinks, maxBytes);
if (docs != null) {
maindoc.addSubDocuments(docs);
if(docs.length > 0 && docs[0].isPartiallyParsed()) {
maindoc.setPartiallyParsed(true);
}
}
} catch (final Exception e) {
throw new Parser.Failure("Unexpected error while parsing gzip file. " + e.getMessage(),location);
}
return maindoc == null ? null : new Document[]{maindoc};
}
/**
* Used to signal an error occurred when opening a gzipped input stream.
*/
public class GZIPOpeningStreamException extends Exception {
/** The serialization ID */
private static final long serialVersionUID = 2824038185373304636L;
public GZIPOpeningStreamException() {
super();
}
public GZIPOpeningStreamException(final String message) {
super(message);
}
}
}
Mini Shell