/**
* $Id: IndexEventConsumer.java 5119 2010-06-16 09:28:50Z benbosman $
* $URL: http://scm.dspace.org/svn/repo/modules/dspace-discovery/trunk/provider/src/main/java/org/dspace/discovery/IndexEventConsumer.java $
* *************************************************************************
* Copyright (c) 2002-2009, DuraSpace. All rights reserved
* Licensed under the DuraSpace License.
*
* A copy of the DuraSpace License has been included in this
* distribution and is available at: http://scm.dspace.org/svn/repo/licenses/LICENSE.txt
*/
package org.dspace.discovery;
import org.apache.log4j.Logger;
import org.dspace.content.Bundle;
import org.dspace.content.DSpaceObject;
import org.dspace.core.Constants;
import org.dspace.core.Context;
import org.dspace.event.Consumer;
import org.dspace.event.Event;
import org.dspace.utils.DSpace;
import java.util.HashSet;
import java.util.Set;
/**
* Class for updating search indices from content events.
*
* @version $Revision: 5119 $
*/
public class IndexEventConsumer implements Consumer {
/**
* log4j logger
*/
private static Logger log = Logger.getLogger(IndexEventConsumer.class);
// collect Items, Collections, Communities that need indexing
private Set<DSpaceObject> objectsToUpdate = null;
// handles to delete since IDs are not useful by now.
private Set<String> handlesToDelete = null;
DSpace dspace = new DSpace();
IndexingService indexer = dspace.getServiceManager().getServiceByName(IndexingService.class.getName(),IndexingService.class);
public void initialize() throws Exception {
}
/**
* Consume a content event -- just build the sets of objects to add (new) to
* the index, update, and delete.
*
* @param ctx DSpace context
* @param event Content event
*/
public void consume(Context ctx, Event event) throws Exception {
if (objectsToUpdate == null) {
objectsToUpdate = new HashSet<DSpaceObject>();
handlesToDelete = new HashSet<String>();
}
int st = event.getSubjectType();
if (!(st == Constants.ITEM || st == Constants.BUNDLE
|| st == Constants.COLLECTION || st == Constants.COMMUNITY)) {
log
.warn("IndexConsumer should not have been given this kind of Subject in an event, skipping: "
+ event.toString());
return;
}
DSpaceObject subject = event.getSubject(ctx);
DSpaceObject object = event.getObject(ctx);
// If event subject is a Bundle and event was Add or Remove,
// transform the event to be a Modify on the owning Item.
// It could be a new bitstream in the TEXT bundle which
// would change the index.
int et = event.getEventType();
if (st == Constants.BUNDLE) {
if ((et == Event.ADD || et == Event.REMOVE) && subject != null
&& ((Bundle) subject).getName().equals("TEXT")) {
st = Constants.ITEM;
et = Event.MODIFY;
subject = ((Bundle) subject).getItems()[0];
if (log.isDebugEnabled())
log.debug("Transforming Bundle event into MODIFY of Item "
+ subject.getHandle());
} else
return;
}
switch (et) {
case Event.CREATE:
case Event.MODIFY:
case Event.MODIFY_METADATA:
if (subject == null)
log.warn(event.getEventTypeAsString() + " event, could not get object for "
+ event.getSubjectTypeAsString() + " id="
+ String.valueOf(event.getSubjectID())
+ ", perhaps it has been deleted.");
else {
log.debug("consume() adding event to update queue: " + event.toString());
objectsToUpdate.add(subject);
}
break;
case Event.REMOVE:
case Event.ADD:
if (object == null)
log.warn(event.getEventTypeAsString() + " event, could not get object for "
+ event.getObjectTypeAsString() + " id="
+ String.valueOf(event.getObjectID())
+ ", perhaps it has been deleted.");
else {
log.debug("consume() adding event to update queue: " + event.toString());
objectsToUpdate.add(object);
}
break;
case Event.DELETE:
String detail = event.getDetail();
if (detail == null)
log.warn("got null detail on DELETE event, skipping it.");
else {
log.debug("consume() adding event to delete queue: " + event.toString());
handlesToDelete.add(detail);
}
break;
default:
log
.warn("IndexConsumer should not have been given a event of type="
+ event.getEventTypeAsString()
+ " on subject="
+ event.getSubjectTypeAsString());
break;
}
}
/**
* Process sets of objects to add, update, and delete in index. Correct for
* interactions between the sets -- e.g. objects which were deleted do not
* need to be added or updated, new objects don't also need an update, etc.
*/
public void end(Context ctx) throws Exception {
if (objectsToUpdate != null && handlesToDelete != null) {
// update the changed Items not deleted because they were on create list
for (DSpaceObject iu : objectsToUpdate) {
/* we let all types through here and
* allow the search DSIndexer to make
* decisions on indexing and/or removal
*/
String hdl = iu.getHandle();
if (hdl != null && !handlesToDelete.contains(hdl)) {
try {
indexer.indexContent(ctx, iu, true);
log.debug("Indexed "
+ Constants.typeText[iu.getType()]
+ ", id=" + String.valueOf(iu.getID())
+ ", handle=" + hdl);
}
catch (Exception e) {
log.error("Failed while indexing object: ", e);
}
}
}
for (String hdl : handlesToDelete) {
try {
indexer.unIndexContent(ctx, hdl, true);
if (log.isDebugEnabled())
log.debug("UN-Indexed Item, handle=" + hdl);
}
catch (Exception e) {
log.error("Failed while UN-indexing object: " + hdl, e);
}
}
}
// "free" the resources
objectsToUpdate = null;
handlesToDelete = null;
}
public void finish(Context ctx) throws Exception {
// No-op
}
}