Hi Gyula,
could you send us en example input which reproduces the problem?
The underlying problem is that the system expects a state to be still
stored in the `SharedBuffer` which has already been removed. This should
actually not happen and it clearly indicates a bug.
Cheers,
Till
On Wed, Sep 7, 2016 at 4:43 PM, Gyula Fóra <gyula.f...@gmail.com> wrote:
> Hi guys,
>
> We tried building a simple pattern with the CEP library that matches 2
> events with 2 filter conditions (where) but we get a strange error that
> comes from the stream operator:
>
> Pattern<Either<View, Click>, ?> viewAndClick = Pattern
> .<Either<View,, Click>> begin("view")
> .where(Either::isLeft)
> .followedBy("click").where(Either::isRight)
> .within(Time.hours(8));
>
> CEP.pattern(stream, pattern).select(...);
>
> We get the following exception when running this:
> java.lang.RuntimeException: Failure happened in filter function.
> at org.apache.flink.cep.nfa.NFA.computeNextStates(NFA.java:318)
> at org.apache.flink.cep.nfa.NFA.process(NFA.java:162)
> at org.apache.flink.cep.operator.KeyedCEPPatternOperator.processEvent(
> KeyedCEPPatternOperator.java:48)
> at org.apache.flink.cep.operator.AbstractCEPBasePatternOperator
> .processElement(AbstractCEPBasePatternOperator.java:72)
> at org.apache.flink.cep.operator.AbstractKeyedCEPPatternOperato
> r.processElement(AbstractKeyedCEPPatternOperator.java:161)
> at org.apache.flink.streaming.runtime.io.StreamInputProcessor.
> processInput(StreamInputProcessor.java:176)
> at org.apache.flink.streaming.runtime.tasks.OneInputStreamTask.run(
> OneInputStreamTask.java:66)
> at org.apache.flink.streaming.runtime.tasks.StreamTask.
> invoke(StreamTask.java:266)
> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:584)
> at java.lang.Thread.run(Thread.java:745)
> Caused by: java.lang.IllegalStateException: Could not find previous
> shared buffer entry with key: State(view, Normal, [
> StateTransition(TAKE, click, with filter),
> StateTransition(IGNORE, view),
> ]), value: Left(View[...]) and timestamp: 1473258371116. This can indicate
> that the element belonging to the previous relation has been already
> pruned, even though you expect it to be still there.
> at org.apache.flink.cep.nfa.SharedBuffer.put(SharedBuffer.java:104)
> at org.apache.flink.cep.nfa.NFA.computeNextStates(NFA.java:295)
> ... 9 more
>
> Any ideas on what's going on here?
>
> Thanks,
> Gyula
>
>
>
