/* Copyright (c) 2012 Google Inc.
*
* Licensed 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 com.google.code.datahub;
import com.google.appengine.api.channel.ChannelMessage;
import com.google.appengine.api.channel.ChannelServiceFactory;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.prospectivesearch.ProspectiveSearchServiceFactory;
import org.json.JSONArray;
import org.json.JSONObject;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* The MatchResponseServlet receives matches and stores them for later
* retrival.
*
* @author Pablo Mayrgundter
*/
public class MatchResponseServlet extends AbstractServlet {
static final long serialVersionUID = 6406691785085268942L;
static final Logger logger = Logger.getLogger(MatchResponseServlet.class.getName());
/**
* Handle Prospective Search match callbacks. Use Channel API to
* synchronously send matching entity to matching query endpoints.
*/
@Override
public void doPost(final HttpServletRequest req, final HttpServletResponse rsp)
throws ServletException, IOException {
int reqResultsOffset = paramToInt("results_offset");
int reqResultsCount = paramToInt("results_count");
if (!paramsOk("Post to matches must specify results_offset and results_count parameters.",
rsp)) {
return;
}
String [] reqQueryIds = req.getParameterValues("id");
logger.fine("MatchResponseServlet: doPost: reqQueryIds: "
+ (java.util.Arrays.toString(reqQueryIds)));
if (reqQueryIds == null || reqQueryIds.length == 0) {
badRequest("Post to matches without a valid list of matching ids: " + reqQueryIds,
rsp);
return;
}
// Plumbing for the next few lines: recode the match from req to
// proto to entity to json.
Entity matchedEntity =
ProspectiveSearchServiceFactory.getProspectiveSearchService().getDocument(req);
if (matchedEntity == null) {
badRequest("Must submit entity for match.", rsp);
return;
}
JSONObject matchedObject = Datastore.entityToJson(matchedEntity);
Path matchPath = Path.fromKey(matchedEntity.getKey());
Util.jsonPut(matchedObject, "path", matchPath);
// Setup the lists of queries to notify. Each client could have
// multiple queries that matched this object.
Map<String, List<QueryId>> queryIdMatchesByEndpoints =
new HashMap<String, List<QueryId>>();
for (String reqQueryId : reqQueryIds) {
QueryId queryId = QueryId.fromString(reqQueryId);
List<QueryId> matchingQueryIds = queryIdMatchesByEndpoints.get(queryId.endpointId);
if (matchingQueryIds == null) {
queryIdMatchesByEndpoints.put(queryId.endpointId,
matchingQueryIds = new ArrayList<QueryId>());
}
matchingQueryIds.add(queryId);
}
logger.fine(
String.format("MatchResponseServlet: doPost: queryIds(%s), matchedObject(%s)\n",
java.util.Arrays.asList(reqQueryIds), matchedObject));
for (Map.Entry<String, List<QueryId>> entry : queryIdMatchesByEndpoints.entrySet()) {
String endpointId = entry.getKey();
List<QueryId> queryIds = entry.getValue();
JSONObject matchMsg = new JSONObject();
Util.jsonPut(matchMsg, "object", matchedObject);
Util.jsonPut(matchMsg, "queryIds", new JSONArray(queryIds));
logger.fine("MatchResponseServlet: delivering json: " + matchMsg);
ChannelServiceFactory.getChannelService()
.sendMessage(new ChannelMessage(endpointId, "(" + matchMsg + ")"));
}
}
}