Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null #15571

pogocode · 2022-12-22T14:44:12Z

Upon session destruction through HttpSession.invalidate(), the following stack trace is often seen:

java.lang.RuntimeException: Push failed
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:200)
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:175)
    at com.vaadin.flow.component.UI.push (UI.java:702)
    at com.vaadin.flow.server.VaadinSession.unlock (VaadinSession.java:718)
    at com.vaadin.flow.server.VaadinService.ensureAccessQueuePurged (VaadinService.java:2025)
    at com.vaadin.flow.server.VaadinService.accessSession (VaadinService.java:1992)
    at com.vaadin.mpr.core.MprServletService.accessSession (MprServletService.java:165)
    at com.vaadin.server.VaadinSession.access (VaadinSession.java:1427)
    at com.vaadin.server.VaadinService.fireSessionDestroy (VaadinService.java:532)
    at com.vaadin.server.VaadinSession.valueUnbound (VaadinSession.java:313)
    at org.eclipse.jetty.server.session.Session.unbindValue (Session.java:349)
    at org.eclipse.jetty.server.session.Session.callSessionAttributeListeners (Session.java:327)
    at org.eclipse.jetty.server.session.Session.finishInvalidate (Session.java:953)
    at org.eclipse.jetty.server.session.SessionHandler.invalidate (SessionHandler.java:1232)
    at org.eclipse.jetty.server.session.DefaultSessionIdManager.invalidateAll (DefaultSessionIdManager.java:486)
    at org.eclipse.jetty.server.session.Session.invalidate (Session.java:854)
    at com.vaadin.flow.server.WrappedHttpSession.invalidate (WrappedHttpSession.java:101)
    at org.vaadin.mprdemo.LegacyView.lambda$attach$0 (LegacyView.java:35)
    at java.util.concurrent.Executors$RunnableAdapter.call (Executors.java:539)
    at java.util.concurrent.FutureTask.run (FutureTask.java:264)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run (ScheduledThreadPoolExecutor.java:304)
    at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1136)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:635)
    at java.lang.Thread.run (Thread.java:833)
Caused by: java.lang.NullPointerException: Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null
    at com.vaadin.flow.server.communication.AtmospherePushConnection.sendMessage (AtmospherePushConnection.java:215)
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:198)
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:175)
    at com.vaadin.flow.component.UI.push (UI.java:702)
    at com.vaadin.flow.server.VaadinSession.unlock (VaadinSession.java:718)
    at com.vaadin.flow.server.VaadinService.ensureAccessQueuePurged (VaadinService.java:2025)
    at com.vaadin.flow.server.VaadinService.accessSession (VaadinService.java:1992)
    at com.vaadin.mpr.core.MprServletService.accessSession (MprServletService.java:165)
    at com.vaadin.server.VaadinSession.access (VaadinSession.java:1427)
    at com.vaadin.server.VaadinService.fireSessionDestroy (VaadinService.java:532)
    at com.vaadin.server.VaadinSession.valueUnbound (VaadinSession.java:313)
    at org.eclipse.jetty.server.session.Session.unbindValue (Session.java:349)
    at org.eclipse.jetty.server.session.Session.callSessionAttributeListeners (Session.java:327)
    at org.eclipse.jetty.server.session.Session.finishInvalidate (Session.java:953)
    at org.eclipse.jetty.server.session.SessionHandler.invalidate (SessionHandler.java:1232)
    at org.eclipse.jetty.server.session.DefaultSessionIdManager.invalidateAll (DefaultSessionIdManager.java:486)
    at org.eclipse.jetty.server.session.Session.invalidate (Session.java:854)
    at com.vaadin.flow.server.WrappedHttpSession.invalidate (WrappedHttpSession.java:101)
    at org.vaadin.mprdemo.LegacyView.lambda$attach$

In turn, this means that any SessionDestroyListeners registered to be executed upon Vaadin session destruction will not be called (see com.vaadin.flow.server.VaadinService#fireSessionDestroy) as the exception is not caught.

Looking at the code, it seems that there is some attempt to guard against the resource being null, but it does appear that the resource is null at the point the push is attempted.

Minimal Reproducible Example

The following application exhibits this behaviour:

mpr-demo-mpr-6-atmosphere-push.zip

Start the application:

mvn -Pproduction jetty:run

Navigate to the following, which will open the view and schedule a session invalidation in 5 seconds time.

http://localhost:8080/legacy

View console output, see stack trace as shown in Actual Behaviour sction

Expected behaviour

All SessionDestroyListeners should be allowed to run as part of session destruction, even in the case of issues with the AtmospherePushConnection.

Actual behaviour

Exception thrown and SessionDestroyListeners not executed:

java.lang.RuntimeException: Push failed
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:200)
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:175)
    at com.vaadin.flow.component.UI.push (UI.java:702)
    at com.vaadin.flow.server.VaadinSession.unlock (VaadinSession.java:718)
    at com.vaadin.flow.server.VaadinService.ensureAccessQueuePurged (VaadinService.java:2025)
    at com.vaadin.flow.server.VaadinService.accessSession (VaadinService.java:1992)
    at com.vaadin.mpr.core.MprServletService.accessSession (MprServletService.java:165)
    at com.vaadin.server.VaadinSession.access (VaadinSession.java:1427)
    at com.vaadin.server.VaadinService.fireSessionDestroy (VaadinService.java:532)
    at com.vaadin.server.VaadinSession.valueUnbound (VaadinSession.java:313)
    at org.eclipse.jetty.server.session.Session.unbindValue (Session.java:349)
    at org.eclipse.jetty.server.session.Session.callSessionAttributeListeners (Session.java:327)
    at org.eclipse.jetty.server.session.Session.finishInvalidate (Session.java:953)
    at org.eclipse.jetty.server.session.SessionHandler.invalidate (SessionHandler.java:1232)
    at org.eclipse.jetty.server.session.DefaultSessionIdManager.invalidateAll (DefaultSessionIdManager.java:486)
    at org.eclipse.jetty.server.session.Session.invalidate (Session.java:854)
    at com.vaadin.flow.server.WrappedHttpSession.invalidate (WrappedHttpSession.java:101)
    at org.vaadin.mprdemo.LegacyView.lambda$attach$0 (LegacyView.java:35)
    at java.util.concurrent.Executors$RunnableAdapter.call (Executors.java:539)
    at java.util.concurrent.FutureTask.run (FutureTask.java:264)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run (ScheduledThreadPoolExecutor.java:304)
    at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1136)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:635)
    at java.lang.Thread.run (Thread.java:833)
Caused by: java.lang.NullPointerException: Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null
    at com.vaadin.flow.server.communication.AtmospherePushConnection.sendMessage (AtmospherePushConnection.java:215)
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:198)
    at com.vaadin.flow.server.communication.AtmospherePushConnection.push (AtmospherePushConnection.java:175)
    at com.vaadin.flow.component.UI.push (UI.java:702)
    at com.vaadin.flow.server.VaadinSession.unlock (VaadinSession.java:718)
    at com.vaadin.flow.server.VaadinService.ensureAccessQueuePurged (VaadinService.java:2025)
    at com.vaadin.flow.server.VaadinService.accessSession (VaadinService.java:1992)
    at com.vaadin.mpr.core.MprServletService.accessSession (MprServletService.java:165)
    at com.vaadin.server.VaadinSession.access (VaadinSession.java:1427)
    at com.vaadin.server.VaadinService.fireSessionDestroy (VaadinService.java:532)
    at com.vaadin.server.VaadinSession.valueUnbound (VaadinSession.java:313)
    at org.eclipse.jetty.server.session.Session.unbindValue (Session.java:349)
    at org.eclipse.jetty.server.session.Session.callSessionAttributeListeners (Session.java:327)
    at org.eclipse.jetty.server.session.Session.finishInvalidate (Session.java:953)
    at org.eclipse.jetty.server.session.SessionHandler.invalidate (SessionHandler.java:1232)
    at org.eclipse.jetty.server.session.DefaultSessionIdManager.invalidateAll (DefaultSessionIdManager.java:486)
    at org.eclipse.jetty.server.session.Session.invalidate (Session.java:854)
    at com.vaadin.flow.server.WrappedHttpSession.invalidate (WrappedHttpSession.java:101)
    at org.vaadin.mprdemo.LegacyView.lambda$attach$0 (LegacyView.java:35)
    at java.util.concurrent.Executors$RunnableAdapter.call (Executors.java:539)
    at java.util.concurrent.FutureTask.run (FutureTask.java:264)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run (ScheduledThreadPoolExecutor.java:304)
    at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1136)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:635)
    at java.lang.Thread.run (Thread.java:833)

Versions:

Vaadin Framework: 8.16.1
Flow: 23.2.5
MPR: 6.0.2
Java JRE / JDK: 17
openjdk 17.0.2 2022-01-18 LTS
OpenJDK Runtime Environment Corretto-17.0.2.8.1 (build 17.0.2+8-LTS)
OpenJDK 64-Bit Server VM Corretto-17.0.2.8.1 (build 17.0.2+8-LTS, mixed mode, sharing)

The text was updated successfully, but these errors were encountered:

pogocode · 2022-12-23T11:28:33Z

Now updated with a minimal application exhibiting this behaviour. It seems that this exception occurs when the HttpSession is invalidated (which could be through some means other than via the Vaadin API, for example if the servlet container decides to destroy the seesion).

pogocode · 2022-12-23T12:28:42Z

I've also confirmed that same issue occurs on Vaadin 23.3.1 / MPR 6.1.0.

TatuLund · 2022-12-23T12:32:34Z

Thanks for the issue report. As this is quite clearly not bug in Vaadin 8, but possibly something either in Flow or MPR, I am going to move the ticket to either one of the repositories.

TatuLund · 2022-12-23T13:05:14Z

MPR 6.1.0.

Just noting that 6.1.1 exists already. https://github.com/vaadin/multiplatform-runtime/releases/tag/6.1.1

TatuLund · 2022-12-23T14:16:12Z

May be related to #14887

And possibly fixed by #15517

mcollovati · 2022-12-23T14:59:09Z

Still happens event with the fix.
I noticed that when push() is invoked the state of AtmospeherePushConnection is CONNECTED, but when sendMessage is called the AtmosphereResource is null.
It seems like that this happens because Vaadin 8 UI.setSession(...) is called with null and it starts a Thread that sets push connection to null, thus invoking disconnect() on Flow PushConnection

https://github.com/vaadin/framework/blob/master/server/src/main/java/com/vaadin/ui/UI.java#L517-L526

mcollovati · 2022-12-23T16:01:19Z

I can confirm that the problem is originated by the thread started by Vaadin 8 to disconnect PUSH.
Now we need to check if this should be fixed in Flow, MPR or Vaadin 8 (less probable)

Disconnecting an AtmospherePushConnection while it is sending a message may result in a NullPointerException if AtmosphereResource is nullified before the message is sent. This change synchronizes operations, so that disconnect will wait until current push finishes, or push waits for disconnect to complete so that the isConnected() method reflects correctly current state. Fixes #15571

* fix: prevent concurrent disconnect and push operations Disconnecting an AtmospherePushConnection while it is sending a message may result in a NullPointerException if AtmosphereResource is nullified before the message is sent. This change synchronizes operations, so that disconnect will wait until current push finishes, or push waits for disconnect to complete so that the isConnected() method reflects correctly current state. Fixes #15571 * fixed test

* fix: prevent concurrent disconnect and push operations Disconnecting an AtmospherePushConnection while it is sending a message may result in a NullPointerException if AtmosphereResource is nullified before the message is sent. This change synchronizes operations, so that disconnect will wait until current push finishes, or push waits for disconnect to complete so that the isConnected() method reflects correctly current state. Fixes #15571 * fixed test Co-authored-by: Marco Collovati <marco@vaadin.com>

Disconnecting an AtmospherePushConnection while it is sending a message may result in a NullPointerException if AtmosphereResource is nullified before the message is sent. This change synchronizes operations, so that disconnect will wait until current push finishes, or push waits for disconnect to complete so that the isConnected() method reflects correctly current state. Fixes #15571

vaadin-bot · 2023-02-08T12:33:54Z

This ticket/PR has been released with Vaadin 23.2.16.

vaadin-bot · 2023-02-09T10:09:33Z

This ticket/PR has been released with Vaadin 23.3.6.

vaadin-bot · 2023-02-13T10:00:01Z

This ticket/PR has been released with Vaadin 14.9.6.

vaadin-bot · 2023-02-14T10:06:44Z

This ticket/PR has been released with Vaadin 24.0.0.beta2 and is also targeting the upcoming stable 24.0.0 version.

TatuLund transferred this issue from vaadin/framework Dec 23, 2022

mcollovati added this to Needs triage in OLD Vaadin Flow bugs & maintenance (Vaadin 10+) via automation Dec 23, 2022

mcollovati added bug Impact: High Severity: Minor labels Dec 23, 2022

mcollovati moved this from Needs triage to New P2 in OLD Vaadin Flow bugs & maintenance (Vaadin 10+) Dec 23, 2022

mcollovati added the MPR label Dec 28, 2022

mcollovati mentioned this issue Jan 27, 2023

fix: prevent concurrent disconnect and push operations #15767

Merged

9 tasks

mshabarov closed this as completed in #15767 Feb 3, 2023

OLD Vaadin Flow bugs & maintenance (Vaadin 10+) automation moved this from New P2 to Closed Feb 3, 2023

mcollovati mentioned this issue Feb 6, 2023

fix: prevent concurrent disconnect and push operations (#15767) (CP: 2.8) #15827

Merged

vaadin-bot added the Released with Vaadin 23.2.16 label Feb 8, 2023

vaadin-bot added the Released with Vaadin 23.3.6 label Feb 9, 2023

vaadin-bot added the Released with Vaadin 14.9.6 label Feb 13, 2023

vaadin-bot added prerelease version for Vaadin 24.0.0 Released with Vaadin 24.0.0.beta2 labels Feb 14, 2023

TatuLund mentioned this issue Nov 30, 2023

NullPointerException in AtmospherePushConnection.sendMessage() vaadin/framework#5776

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Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null #15571

Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null #15571

pogocode commented Dec 22, 2022 •

edited

pogocode commented Dec 23, 2022

pogocode commented Dec 23, 2022

TatuLund commented Dec 23, 2022

TatuLund commented Dec 23, 2022

TatuLund commented Dec 23, 2022

mcollovati commented Dec 23, 2022 •

edited

mcollovati commented Dec 23, 2022

vaadin-bot commented Feb 8, 2023

vaadin-bot commented Feb 9, 2023

vaadin-bot commented Feb 13, 2023

vaadin-bot commented Feb 14, 2023

Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null #15571

Cannot invoke "org.atmosphere.cpr.AtmosphereResource.getBroadcaster()" because the return value of "com.vaadin.flow.server.communication.AtmospherePushConnection.getResource()" is null #15571

Comments

pogocode commented Dec 22, 2022 • edited

Minimal Reproducible Example

Expected behaviour

Actual behaviour

Versions:

pogocode commented Dec 23, 2022

pogocode commented Dec 23, 2022

TatuLund commented Dec 23, 2022

TatuLund commented Dec 23, 2022

TatuLund commented Dec 23, 2022

mcollovati commented Dec 23, 2022 • edited

mcollovati commented Dec 23, 2022

vaadin-bot commented Feb 8, 2023

vaadin-bot commented Feb 9, 2023

vaadin-bot commented Feb 13, 2023

vaadin-bot commented Feb 14, 2023

pogocode commented Dec 22, 2022 •

edited

mcollovati commented Dec 23, 2022 •

edited