Hello, We are building a flink use case where we are consuming from a kafka topic and performing aggregations and generating alerts based on average, max, min thresholds. We also need to notify the users when there are 0 events in a Tumbling Event Time Windows. We are having trouble coming up with a solution to do the same. The options we considered are below, please let us know if there are other ideas we haven't looked into.
[1] Querable State : Save the keys in each of the Process Window Functions. Query the state from an external application and alert when a key is missing after the 20min time interval has expired. We see Queryable state feature is being deprecated in the future. We do not want to go down this path when we already know there is an EOL for it. [2] Use Processing Time Windows : Using Processing time instead of Event time would have been an option if our downstream applications would send out events in real time. Maintenances of the downstream applications, delays etc would result in a lot of data loss which is undesirable. Flink version : 1.14.3 Thanks, Shilpa
