Kafka on-change/hysteresis support

[dremsol]

Currently the Kafka Connect integration supports polling-based data acquisition. This results in duplicate messages when values don't change. Although some drivers support subscription not all devices seem to support it so a general implementation seems to be infeasible. What would be the best approach to on-change/hysteresis support in the Kafka integration?

[hutcheb]

Hi Willem,

Each driver has the canRead, canWrite and canSubscribe attributes, these can be used to decide between using a subscription based connection and a read connection. I'm not 100% sure where to put this logic though, somewhere within the Scraper?

Ben

On Fri, Nov 18, 2022 at 7:40 AM Willem Remie @.***> wrote:

Currently the Kafka Connect integration supports polling-based data acquisition. This results in duplicate messages when values don't change. Although some drivers support subscription not all devices seem to support it so a general implementation seems to be infeasible. What would be the best approach to on-change/hysteresis support in the Kafka integration?

— Reply to this email directly, view it on GitHub https://github.com/apache/plc4x/issues/659, or unsubscribe https://github.com/notifications/unsubscribe-auth/ADXBWTA6KJGRJNTWTJ2SEQDWI6BOJANCNFSM6AAAAAASEQCYIM . You are receiving this because you are subscribed to this thread.Message ID: @.***>

[chrisdutz]

We also have thought of implementing some "fake subscription" support based on polling, if a driver doesn't directly support subscriptions. However nobody ever volunteered to take on this action ... am I hearing a volunteer? ;-)

[chrisdutz]

Are we really waiting for feedback here? Otherwise I think we might close this issue.