//rssParser.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
//last major change: 16.05.2005
//
//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 de.anomic.plasma.parser.rss;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.Writer;
import java.nio.charset.Charset;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.LinkedList;
import java.util.Map;
import de.anomic.htmlFilter.htmlFilterAbstractScraper;
import de.anomic.htmlFilter.htmlFilterContentScraper;
import de.anomic.htmlFilter.htmlFilterImageEntry;
import de.anomic.htmlFilter.htmlFilterWriter;
import de.anomic.kelondro.util.ByteBuffer;
import de.anomic.kelondro.util.FileUtils;
import de.anomic.plasma.plasmaParserDocument;
import de.anomic.plasma.parser.AbstractParser;
import de.anomic.plasma.parser.Parser;
import de.anomic.plasma.parser.ParserException;
import de.anomic.server.serverCharBuffer;
import de.anomic.xml.RSSFeed;
import de.anomic.xml.RSSMessage;
import de.anomic.xml.RSSReader;
import de.anomic.yacy.yacyURL;
public class rssParser extends AbstractParser implements Parser {
/**
* a list of mime types that are supported by this parser class
* @see #getSupportedMimeTypes()
*/
public static final Hashtable<String, String> SUPPORTED_MIME_TYPES = new Hashtable<String, String>();
static {
SUPPORTED_MIME_TYPES.put("text/rss","xml,rss,rdf");
SUPPORTED_MIME_TYPES.put("application/rdf+xml","xml,rss,rdf");
SUPPORTED_MIME_TYPES.put("application/rss+xml","xml,rss,rdf");
SUPPORTED_MIME_TYPES.put("application/atom+xml","xml,atom");
}
/**
* a list of library names that are needed by this parser
* @see Parser#getLibxDependences()
*/
private static final String[] LIBX_DEPENDENCIES = new String[] {};
public rssParser() {
super(LIBX_DEPENDENCIES);
this.parserName = "Rich Site Summary/Atom Feed Parser";
}
public plasmaParserDocument parse(final yacyURL location, final String mimeType, final String charset, final InputStream source) throws ParserException, InterruptedException {
try {
final LinkedList<String> feedSections = new LinkedList<String>();
final HashMap<yacyURL, String> anchors = new HashMap<yacyURL, String>();
final HashMap<String, htmlFilterImageEntry> images = new HashMap<String, htmlFilterImageEntry>();
final ByteBuffer text = new ByteBuffer();
final serverCharBuffer authors = new serverCharBuffer();
final RSSFeed feed = new RSSReader(source).getFeed();
if (feed == null) throw new ParserException("no feed in document",location);
if (feed.getChannel() == null) throw new ParserException("no channel in document",location);
// getting the rss feed title and description
final String feedTitle = feed.getChannel().getTitle();
// getting feed creator
final String feedCreator = feed.getChannel().getAuthor();
if (feedCreator != null && feedCreator.length() > 0) authors.append(",").append(feedCreator);
// getting the feed description
final String feedDescription = feed.getChannel().getDescription();
if (feed.getImage() != null) {
final yacyURL imgURL = new yacyURL(feed.getImage(), null);
images.put(imgURL.hash(), new htmlFilterImageEntry(imgURL, feedTitle, -1, -1));
}
// loop through the feed items
for (final RSSMessage item: feed) {
// check for interruption
checkInterruption();
final String itemTitle = item.getTitle();
final yacyURL itemURL = new yacyURL(item.getLink(), null);
final String itemDescr = item.getDescription();
final String itemCreator = item.getCreator();
if (itemCreator != null && itemCreator.length() > 0) authors.append(",").append(itemCreator);
feedSections.add(itemTitle);
anchors.put(itemURL, itemTitle);
if ((text.length() != 0) && (text.byteAt(text.length() - 1) != 32)) text.append((byte) 32);
text.append(htmlFilterAbstractScraper.stripAll(itemDescr).trim()).append(' ');
final String itemContent = item.getDescription();
if ((itemContent != null) && (itemContent.length() > 0)) {
final htmlFilterContentScraper scraper = new htmlFilterContentScraper(itemURL);
final Writer writer = new htmlFilterWriter(null, null, scraper, null, false);
FileUtils.copy(new ByteArrayInputStream(itemContent.getBytes("UTF-8")), writer, Charset.forName("UTF-8"));
final String itemHeadline = scraper.getTitle();
if ((itemHeadline != null) && (itemHeadline.length() > 0)) {
feedSections.add(itemHeadline);
}
final Map<yacyURL, String> itemLinks = scraper.getAnchors();
if ((itemLinks != null) && (itemLinks.size() > 0)) {
anchors.putAll(itemLinks);
}
final HashMap<String, htmlFilterImageEntry> itemImages = scraper.getImages();
if ((itemImages != null) && (itemImages.size() > 0)) {
htmlFilterContentScraper.addAllImages(images, itemImages);
}
final byte[] extractedText = scraper.getText();
if ((extractedText != null) && (extractedText.length > 0)) {
if ((text.length() != 0) && (text.byteAt(text.length() - 1) != 32)) text.append((byte) 32);
text.append(scraper.getText());
}
}
}
final plasmaParserDocument theDoc = new plasmaParserDocument(
location,
mimeType,
"UTF-8",
null,
null,
feedTitle,
(authors.length() > 0)?authors.toString(1,authors.length()):"",
feedSections.toArray(new String[feedSections.size()]),
feedDescription,
text.getBytes(),
anchors,
images);
// close streams
text.close();
authors.close();
return theDoc;
} catch (final InterruptedException e) {
throw e;
} catch (final IOException e) {
throw new ParserException("Unexpected error while parsing rss file." + e.getMessage(),location);
}
}
public Hashtable<String, String> getSupportedMimeTypes() {
return SUPPORTED_MIME_TYPES;
}
public void reset() {
// Nothing todo here at the moment
super.reset();
}
}