RisingWave Community - Is it possible to guarantee exactly-once consumption in a system like RW when polling a HTTP endpoint for updates?

Guaranteeing exactly-once consumption in a system like RW when polling a HTTP endpoint for updates is challenging due to the nature of polling and potential retries.
One way to work around this challenge is by using an upsert strategy, where SQL calls wrap a select with a conditional update or insert in a transaction.
Deletes can still pose a problem in ensuring exactly-once consumption.
While challenging, having support for HTTP polling source in RW could be very beneficial for certain use cases.