You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@flink.apache.org by Radu Tudoran <ra...@huawei.com> on 2016/09/22 08:44:22 UTC

emit watermarks

Hi,

Is there some way to emit a watermark in the trigger?

I see that in the evictor there is the option to check the StreamRecord<Object> if it is a watermark..so I would hope that there is some option also to create them


Re: emit watermarks

Posted by Kostas Kloudas <k....@data-artisans.com>.
Hi Radu,

Watermarks cannot be emitted by the triggers.
Their responsibility is just to tell the operator to do (or not do) sth 
with the data it has gathered. Thus the name Trigger :P. 

Eviction policies allow you to also filter some elements out 
before applying your function. But that is as far as it goes 
concerning input element modification.

For emitting watermarks you should look at the 
assignTimestampsAndWatermarks methods in the 
DataStream API.

Cheers,
Kostas
 
> On Sep 22, 2016, at 10:44 AM, Radu Tudoran <ra...@huawei.com> wrote:
> 
>  
> Hi,
>  
> Is there some way to emit a watermark in the trigger?
>  
> I see that in the evictor there is the option to check the StreamRecord<Object> if it is a watermark..so I would hope that there is some option also to create them