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From Matt Burgess <>
Subject Re: Externally update processor State
Date Mon, 15 Aug 2016 20:23:48 GMT

Updating an "Initial Max Value" property could set the state when the
processor is started, so you wouldn't need to clear state unless your
Initial Max Value is less than what is in state currently.


On Mon, Aug 15, 2016 at 4:16 PM, Peter Wicks (pwicks) <> wrote:
> Joe,
> So the solution would is to customize QueryDatabaseTable to support reading the initial
state Max Value(s) from a property. Then, if I want to change the existing state I stop the
processor, clear the state, update my initial Max Value, and start the processor again?
> --Peter
> -----Original Message-----
> From: Joe Witt []
> Sent: Monday, August 15, 2016 2:06 PM
> To:
> Subject: Re: Externally update processor State
> Peter,
> Ok understood.  I feel like the QueryDatabaseTable processor should have a property for
exactly this.  And there is already a clear and well managed model and REST API for operating
on those.  Does that sound like a fair alternative?
> Thanks
> JOe
> On Mon, Aug 15, 2016 at 1:03 PM, Peter Wicks (pwicks) <> wrote:
>> Joe,
>> The specific use cases at the moment both surround QueryDatabaseTable and its Max
Value Column tracking.
>> First, I'd like to be able to set an initial value for a max value column; so essentially
an initial state value. The idea would be to support situations where we want to start loading
data only from the last 'x' time period.
>> Secondly, if something happened downstream and we need to roll back the clock I want
our operations team to be able to stop the processor, change the timestamp to the necessary
value, and then start the processor back up as part of their resolution process.
>> Regards,
>>   Peter
>> -----Original Message-----
>> From: Joe Witt []
>> Sent: Monday, August 15, 2016 1:51 PM
>> To:
>> Subject: Re: Externally update processor State
>> Peter,
>> The state management function the is built-in is to allow processors to set/interact
with their own managed state.  We did not intend for that to be something someone external
to the processor could interact with directly.  Rather, that is what properties are expected
to be used for.
>> So far the couple of requests like this I've seen are where there is a sort of human
in the process flow going on - like a workflow manager.
>> Can you describe the details of your use case/ideal user experience a bit further?
>> Thanks
>> Joe
>> On Mon, Aug 15, 2016 at 12:22 PM, Peter Wicks (pwicks) <>
>>> I'm looking for a way to externally update a processors state, preferably through
an API call and then at some point the existing State viewer with the clear button. From digging
through the code base I couldn't find an exposed API that would allow for state modification;
only a state clearing.
>>> Was there a design decision behind this, or is this a feature waiting to be added?
>>> Regards,
>>>   Peter

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