// suggest.java
// -----------------------
// (C) 2010 by Michael Peter Christen; mc@yacy.net
// first published 11.10.2010 in Frankfurt, Germany on http://yacy.net
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// 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
import java.util.Iterator;
import net.yacy.cora.protocol.HeaderFramework;
import net.yacy.cora.protocol.RequestHeader;
import net.yacy.cora.protocol.ResponseHeader;
import net.yacy.kelondro.data.word.Word;
import net.yacy.search.Switchboard;
import net.yacy.search.index.Segment;
import net.yacy.search.index.Segments;
import de.anomic.data.DidYouMean;
import de.anomic.server.serverObjects;
import de.anomic.server.serverSwitch;
import de.anomic.server.servletProperties;
/**
* for json format:
* implementation of the opensearch suggestion extension, see
* http://www.opensearch.org/Specifications/OpenSearch/Extensions/Suggestions/1.1
* or
* https://wiki.mozilla.org/Search_Service/Suggestions
*
* for xml format:
* see Microsoft Search Suggestion Format
* http://msdn.microsoft.com/en-us/library/cc848863%28VS.85%29.aspx
* and
* http://msdn.microsoft.com/en-us/library/cc848862%28v=VS.85%29.aspx
*/
public class suggest {
private static final int meanMax = 30;
public static serverObjects respond(final RequestHeader header, final serverObjects post, final serverSwitch env) {
final Switchboard sb = (Switchboard) env;
final servletProperties prop = new servletProperties();
final String ext = header.get("EXT", "");
final boolean json = ext.equals("json");
final boolean xml = ext.equals("xml");
final boolean more = post != null && post.containsKey("more");
// get query
final String originalquerystring = (post == null) ? "" : post.get("query", post.get("q", "")).trim();
final String querystring = originalquerystring.replace('+', ' ');
final int timeout = (post == null) ? 300 : post.getInt("timeout", 300);
final int count = (post == null) ? 20 : post.getInt("count", 20);
// get segment
final Segment indexSegment;
if (post != null && post.containsKey("segment")) {
final String segmentName = post.get("segment");
if (sb.indexSegments.segmentExist(segmentName)) {
indexSegment = sb.indexSegments.segment(segmentName);
} else {
// take default segment
indexSegment = sb.indexSegments.segment(Segments.Process.PUBLIC);
}
} else {
// take default segment
indexSegment = sb.indexSegments.segment(Segments.Process.PUBLIC);
}
int c = 0;
if (more ||
(indexSegment != null &&
!indexSegment.termIndex().has(Word.word2hash(querystring))))
{
final DidYouMean didYouMean = new DidYouMean(indexSegment.termIndex(), new StringBuilder(querystring));
final Iterator<StringBuilder> meanIt = didYouMean.getSuggestions(timeout, count).iterator();
String suggestion;
//[#[query]#,[#{suggestions}##[text]##(eol)#,::#(/eol)##{/suggestions}#]]
while (c < meanMax && meanIt.hasNext()) {
suggestion = meanIt.next().toString();
if (json) {
prop.putJSON("suggestions_" + c + "_text", suggestion);
} else if (xml) {
prop.putXML("suggestions_" + c + "_text", suggestion);
} else {
prop.putHTML("suggestions_" + c + "_text", suggestion);
}
prop.put("suggestions_" + c + "_eol", 0);
c++;
}
}
if (c > 0) {
prop.put("suggestions_" + (c - 1) + "_eol", 1);
}
prop.put("suggestions", c);
if (json) {
prop.putJSON("query", originalquerystring);
} else if (xml) {
prop.putXML("query", originalquerystring);
} else {
prop.putHTML("query", originalquerystring);
}
// Adding CORS Access header for xml output
if (xml) {
final ResponseHeader outgoingHeader = new ResponseHeader();
outgoingHeader.put(HeaderFramework.CORS_ALLOW_ORIGIN, "*");
prop.setOutgoingHeader(outgoingHeader);
}
// return rewrite properties
return prop;
}
}