Sometimes writing it down makes you think. I now realize that this is not
the right approach, given that merging windows will have their own
states..and how the merge happens is really at the key level....
On Fri, Mar 12, 2021 at 6:27 AM Vishal Santoshi <vishal.santo...@gmail.com>
wrote:
> I intend to augment every event in a session with a unique ID. To keep
> the session lean, there is a PurgingTrigger on this aggregate that fires
> on a count of 1.
>
> >> (except that the number of keys can grow).
>
> Want to confirm that the keys are GCed ( along with state ) once the
> (windows close + lateness ) ?
>
>
>
> On Fri, Mar 12, 2021 at 5:32 AM Roman Khachatryan <ro...@apache.org>
> wrote:
>
>> Hi Vishal,
>>
>> There is no leak in the code you provided (except that the number of
>> keys can grow).
>> But as you figured out the state is scoped to key, not to window+key.
>>
>> Could you explain what you are trying to achieve and why do you need to
>> combine
>> sliding windows with state scoped to window+key?
>>
>> Regards,
>> Roman
>>
>> On Fri, Mar 12, 2021 at 5:13 AM Vishal Santoshi
>> <vishal.santo...@gmail.com> wrote:
>> >
>> > Essentially, Does this code leak state
>> >
>> > private static class SessionIdProcessWindowFunction<KEY extends
>> java.io.Serializable, VALUE extends java.io.Serializable>
>> > extends
>> > ProcessWindowFunction<KeyedSession<KEY, VALUE>,
>> KeyedSessionWithSessionID<KEY, VALUE>, KEY, TimeWindow> {
>> > private static final long serialVersionUID = 1L;
>> > private final static ValueStateDescriptor<String> sessionId = new
>> ValueStateDescriptor<String>("session_uid",
>> > String.class);
>> >
>> > @Override
>> > public void process(KEY key,
>> > ProcessWindowFunction<KeyedSession<KEY, VALUE>,
>> KeyedSessionWithSessionID<KEY, VALUE>, KEY, TimeWindow>.Context context,
>> > Iterable<KeyedSession<KEY, VALUE>> elements,
>> Collector<KeyedSessionWithSessionID<KEY, VALUE>> out)
>> > throws Exception {
>> > // I need this scoped to key/window
>> > if (getRuntimeContext().getState(sessionId).value() == null) {
>> > UUID uuid = UUID.randomUUID();
>> > getRuntimeContext().getState(sessionId).update(uuid.toString());
>> > }
>> > String uuid = getRuntimeContext().getState(sessionId).value();
>> > out.collect(new KeyedSessionWithSessionID<>(elements.iterator().next(),
>> uuid));
>> > }
>> > }
>> >
>> > On Thu, Mar 11, 2021 at 11:09 PM Vishal Santoshi <
>> vishal.santo...@gmail.com> wrote:
>> >>
>> >> Hello folks,
>> >> The suggestion is to use windowState() for a key key
>> per window state and clear the state explicitly. Also it seems that
>> getRuntime().getState() will return a globalWindow() where state is shared
>> among windows with the same key. I desire of course to have state scoped to
>> a key per window and was wanting to use windowState().. The caveat is that
>> my window is a Session Window and when I try to use clear() I am thrown
>> this exception ( Session Windows are Merging Windows )
>> >>
>> >> Caused by: java.lang.UnsupportedOperationException: Per-window state
>> is not allowed when using merging windows.
>> >>
>> >>
>> >> The questions are
>> >>
>> >> * How do I have state per session window/ per key and still be able to
>> clear it ?
>> >> * Does getRuntime().getState() give me the clear() semantics for free
>> along with state per window per key and thus I have understood
>> getRuntime().getState() wrong ?
>> >>
>> >> Regards.
>> >>
>> >>
>> >>
>>
>
