KeyValue.keys() includes purged keys immediately after purge(key)

[drse]

I'm implementing event/snapshot deletion for a NATS-backed persistence layer. After calling kv.purge(key), kv.keys() sometimes still includes the purged key in the returned list. A subsequent kv.get(key) correctly returns null.

This appears to be a sync issue — the keys() watcher may not have processed the purge marker yet when called immediately after purge().

Questions:

1. Is keys() guaranteed to reflect purge() immediately, or is there an expected propagation delay?
2. If there is a delay, is there a recommended way to force consistency (e.g., calling purgeDeletes() after purge())?
3. Does the same apply to delete(key) — can keys() briefly include soft-deleted keys?

Using nats client lib v2.25.2 against a 2.12.6 server.

[scottf]

There are definitely timing issues, but understand that the soft delete is actually a message. Depending on how you have your watcher set up, you might get those messages or keys until the actual purge of the subject is complete.

[drse]

Got it, thanks. Is there a recommended way to know when the key is fully gone, or should we always cross-check keys() results with get()?