This also happens in Wildfly 8.1 (Undertow 1.0.15) and can happen if
the browser doesn't close the connection when the tab is closed.
Chrome and IE both do this.

https://issues.jboss.org/browse/WFLY-3704

Supposedly fixed in later versions but I haven't upgraded yet to verify.

On Tue, Oct 21, 2014 at 9:07 AM, Vladimir Tsukur <flushdia@gmail.com> wrote:
> One more observation - in case network connection is completely lost in
> between client and server, "close" notifiers are not invoked at all (tried
> by shutting down network connection on the client machine keeping browser
> tab opened). In this case there is no opportunity for a client to send a
> close frame to the server. Is it a bug then? Using Undertow 1.2.0.Beta1
>
> On Tue, Oct 21, 2014 at 4:10 PM, Vladimir Tsukur <flushdia@gmail.com> wrote:
>>
>> Thanks Stuart,
>>
>> Did not see this method in 1.0.x since it was added at a later release -
>> tried with latest version and it works well.
>>
>> However, I figured out that connection termination works well iif receive
>> setter is set:
>>
>>     WebSocketChannel channel = ...;
>>     channel.getReceiveSetter().set(new AbstractReceiveListener() {});
>>     channel.addCloseTask(new ChannelListener<WebSocketChannel>() {
>>         @Override
>>         public void handleEvent(WebSocketChannel channel) {
>>             ...
>>         }
>>     });
>>
>> If receive setter is not set, then close task will not be called. In my
>> case there was no intent to receive messages from the client and just push
>> them from the server. Receive setter was not set => connection was not
>> closed.
>>
>> It seems obligatory to set receive setter all the time to make the thing
>> work. Is it intended? While it is not a big deal really, I would imagine
>> that Undertow should handle connection termination without explicit receive
>> setter call made by the API client.
>>
>>
>> On Tue, Oct 21, 2014 at 2:08 AM, Stuart Douglas <sdouglas@redhat.com>
>> wrote:
>>>
>>> WebsocketChannel.addCloseTask() should do what you are after (this is
>>> actually provided by the base AbstractFramedChannel class).
>>>
>>> Stuart
>>>
>>> ----- Original Message -----
>>> > From: "Vladimir Tsukur" <flushdia@gmail.com>
>>> > To: undertow-dev@lists.jboss.org
>>> > Sent: Tuesday, 21 October, 2014 7:20:54 AM
>>> > Subject: [undertow-dev] Handling termination of WebSocket connection
>>> >
>>> > Let's imagine user closed browser tab and thus terminated WebSocket
>>> > connection. Is there any way to run a callback method on the
>>> > server-side to
>>> > handle this case?
>>> >
>>> > The requirement is to perform necessary cleanup actions when connection
>>> > is
>>> > closed, regardless of the type of disconnect (normal, forced
>>> > termination,
>>> > etc.).
>>> >
>>> > (Ideally using lower level API, and not JSR 356)
>>> >
>>> > --
>>> > Vladimir Tsukur
>>> > Software Architect, Design Engineer
>>> >
>>> > _______________________________________________
>>> > undertow-dev mailing list
>>> > undertow-dev@lists.jboss.org
>>> > https://lists.jboss.org/mailman/listinfo/undertow-dev
>>
>>
>>
>>
>> --
>> Vladimir Tsukur
>> Software Architect, Design Engineer
>
>
>
>
> --
> Vladimir Tsukur
> Software Architect, Design Engineer
>
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