On Fri, Sep 28, 2012 at 12:02 PM, Paul Libbrecht <paul(a)hoplahup.net> wrote: It should not, a document event for example is send after the document is saved in the database so if you react to this event you can't invalidate the cache too early. IMO there is only two possibilities here: * the listener that is supposed to invalidate the cache does not receive the event for some reason * there is no such listener or it's buggy Indeed. -- Thomas Mortagne

On Fri, Sep 28, 2012 at 10:29 PM, Paul Libbrecht <paul(a)hoplahup.net> wrote: The canonical way to check if you are called by a remote event is by using the component org.xwiki.observation.remote.RemoteObservationManagerContex#isRemoteState() (from xwiki-platform-observation-remote). LazyXWikiDocument is what is used when emulating a document event from the remote observation module. It's actually supposed to behave like a XWikiDocument except that it actually load the document from the database only if something actually need to manipulate it. The only thing for which it's not supposed to work well is if you try to save it directly but it's not recommended for a document coming in a local event anyway since it's creating an events mess. So unless you really have a specific logic that need to do different things from local and remote events the best would be that we fix what's wrong with LazyXWikiDocument in your use case. -- Thomas Mortagne

On Mon, Oct 1, 2012 at 12:04 PM, Paul Libbrecht <paul(a)hoplahup.net> wrote: If you know how to get a component in Groovy already you can do lookup the component with role org.xwiki.observation.remote.RemoteObservationManagerContex and default hint. What version of XWiki is that ? Actually there is several other listener that look at previous version (for example there is listener that check differences and produce more precise event about object, object properties, classes, attachments, etc.) so at least in most recent versions it's supposed to work. -- Thomas Mortagne

On Tue, Oct 2, 2012 at 11:10 AM, Paul Libbrecht <paul(a)hoplahup.net> wrote: OK will try with 50 and see what I get. Not sure how this could be related unless it makes the LazyXWikiDocument fail to get the document from the database for some weird reason. Same database and jdbc connector versions ? -- Thomas Mortagne

The story evolved down here. I have crafted an extra observer that listens to notifications and checks if the values are the same when in event and one second later in a spawned thread. They're not. The code is copied below, it is inspired from the nice tutorial about observation. Since about 36h, the observation listener below has reported 967 saves. From them, 145 indicate the warning at the end of this code. This warning indicates that the title, number of a objects of a particular class (where we observed the bug first), or version differ: - when pulled from the source of the event (XWikiDocument or LazyXWikiDocument) - or when pulled one second later with xwiki.getXWiki().getDocument(). However, and that's the crusty bit. Somehow, the attempt to reproduce the bug have almost all failed since that time as well. (no systematic way to reproduce the bug has been found, neither has there been a page that stayed different between the two nodes). We're on hold but this is a rather good surprise! Paul // {{groovy}} // This page should be Util.TryObservation // import org.xwiki.observation.* import org.xwiki.observation.event.* import com.xpn.xwiki.web.* import com.xpn.xwiki.* import org.xwiki.bridge.event.DocumentUpdatedEvent import com.xpn.xwiki.doc.XWikiDocument import org.apache.commons.logging.Log import org.apache.commons.logging.LogFactory import com.xpn.xwiki.util.AbstractXWikiRunnable import org.xwiki.observation.remote.RemoteObservationManagerContext class TryObservation implements EventListener { static final Log LOG = LogFactory.getLog("groovyPages.Sandbox.TryObservation"); boolean DEBUG = LOG.isDebugEnabled(); XWiki xwiki XWikiContext xcontext TryObservation(xwiki, xcontext) { this.xwiki = xwiki this.xcontext = xcontext } String getName() { // The unique name of this event listener return "Changes-Version-Checker" } List<Event> getEvents() { // The list of events this listener listens to return Arrays.asList(new DocumentUpdatedEvent()) } // Called by the Observation Manager when an event matches the list of events returned // by getEvents() void onEvent(Event event, Object source, Object data) { XWikiDocument xdoc = source; LOG.warn("Received event: " + event + ", source: " + source); LOG.warn("Title of changed document " + xdoc.getTitle()) LOG.warn("Version of changed document " + xdoc.getVersion()) int count = 0; List o = xdoc.getObjects("CurrikiCode.SubAssetClass"); if(o!=null) count = o.size() LOG.warn("Number of children: " + count); LOG.warn("Is remote? " + Utils.getComponent(RemoteObservationManagerContext.class).isRemoteState()); Thread obs = new Thread(new DelayedObserver(xwiki, xcontext, xdoc.getFullName(), xdoc.getTitle(), xdoc.getVersion(), count),"delayed obs"); obs.start(); LOG.warn("started obs " + obs); // Prevent infinite recursion since in this example we log to wiki page which // triggers a document change... :) /* if (source.fullName != "Sandbox.TryObservation") { def document = xwiki.getDocument("Sandbox.TryObservation") document.setContent("${document.getContent()}\n${source.fullName} has changed") document.save("Logging event", true) } */ } public static class DelayedObserver extends AbstractXWikiRunnable { public DelayedObserver(XWiki xwiki, XWikiContext context, String fullName, String inEventTitle, String inEventVersion, int inEventCount) { super(XWikiContext.EXECUTIONCONTEXT_KEY, context.clone()); LOG.warn("(delayed) delayed observer initting. ") this.xwiki = xwiki; this.fullName = fullName; this.context = context; this.inEventTitle = inEventTitle; this.inEventVersion = inEventVersion; this.inEventCount = inEventCount; } private XWiki xwiki; private XWikiContext context; private String fullName, inEventTitle, inEventVersion; private int inEventCount; public void runInternal() { try { Thread.currentThread().setName("delayed observer " + fullName); LOG.warn("(delayed) delayed observer starting. ") Thread.sleep(1000); XWikiDocument doc = xwiki.getDocument(fullName, context); LOG.warn("(delayed) Title of changed document " + doc.getTitle()) LOG.warn("(delayed) Version of changed document " + doc.getVersion()) int count = 0; List o = doc.getObjects("CurrikiCode.SubAssetClass"); if(o!=null) count = o.size() LOG.warn("(delayed) Number of children: " + count); LOG.warn("(delayed) Is remote? " + Utils.getComponent(RemoteObservationManagerContext.class).isRemoteState()); if(!(inEventVersion==doc.getVersion() && inEventTitle==doc.getTitle() && count == inEventCount)) { LOG.error("(delayed) WARNING: inEvent and and delayed do not match!!"); } } catch (Exception ex) { LOG.warn("Exception at the delayed bit: "+ ex, ex); } } } } // Register against the Observation Manager def observation = Utils.getComponent(ObservationManager.class) observation.removeListener("Changes-Version-Checker") def listener = new TryObservation(xwiki.getXWiki(), xcontext.getContext()) observation.addListener(listener) // {{/groovy}}

On Tue, Oct 9, 2012 at 9:47 AM, Thomas Mortagne &lt;thomas.mortagne(a)xwiki.com&gt; wrote: I mean during the 1s you waited. -- Thomas Mortagne