flink-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF GitHub Bot (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (FLINK-8384) Session Window Assigner with Dynamic Gaps
Date Wed, 31 Jan 2018 15:07:00 GMT

    [ https://issues.apache.org/jira/browse/FLINK-8384?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16346972#comment-16346972

ASF GitHub Bot commented on FLINK-8384:

Github user dyanarose commented on the issue:

    I'm not the biggest fan of unchecked casts, but testing this in our POC environment casting
the existing EventTimeTrigger to a typed Trigger<T, W> is working. So if the unchecked
cast is acceptable, that would get rid of all changes required to Event/ProcessingTimeTrigger
    On your second point. (sorry if I mis-attribute this based on github profile name) I believe
you had mentioned breaking this out into new classes when I first brought this up on the mailing
list https://lists.apache.org/thread.html/6ceb094460bca8e9731e9e1dc0bb479f407f769458bff30c412adf78@%3Cdev.flink.apache.org%3E
    Now that you see it in action, do you feel it would be better off as an addition to the
existing session window classes?
    The way I see it is, if I put withGapExtractor() on the existing classes, without adding
type information to them, then the extract() method on SessionWindowGapExtractor will need
to have the signature of extract(Object input) leaving the implementer to have to cast to
the input type.
    I have to admit it feels strange to me that the Window assigners all drop input type information.
But that would mean that these new typed assigners would be the odd ones out.

> Session Window Assigner with Dynamic Gaps
> -----------------------------------------
>                 Key: FLINK-8384
>                 URL: https://issues.apache.org/jira/browse/FLINK-8384
>             Project: Flink
>          Issue Type: Improvement
>          Components: Streaming
>            Reporter: Dyana Rose
>            Priority: Minor
> *Reason for Improvement*
> Currently both Session Window assigners only allow a static inactivity gap. 
> Given the following scenario, this is too restrictive:
> * Given a stream of IoT events from many device types
> * Assume each device type could have a different inactivity gap
> * Assume each device type gap could change while sessions are in flight
> By allowing dynamic inactivity gaps, the correct gap can be determined in the [assignWindows
by passing the element currently under consideration, the timestamp, and the context to a
user defined function. This eliminates the need to create unwieldy work arounds if you only
have static gaps.
> Dynamic Session Window gaps should be available for both Event Time and Processing Time
> (short preliminary discussion: https://lists.apache.org/thread.html/08a011c0039e826343e9be0b1bb4e0000cfc2e12976bc65f8a43ee88@%3Cdev.flink.apache.org%3E)

This message was sent by Atlassian JIRA

View raw message