NATS JetStream support

[Saphri]

Adding support for using NATS JetSteam key-value stores as lock backend

[lukas-krecan]

Thanks a lot, I will look at it soon

[lukas-krecan]

Hi, thanks again. It seems to me, that there is another limitation, lockAtLeastFor/Until actually does not work, if the task takes shorter than lockAtLeastFor, the lock is held for lockAtMostFor, do I get it right? If that's so, let's log a warning if lockAtleast for is nonzero and mention it in the documentation. Any idea when NATS 2.11 should be released?

[Saphri]

Yes you are correct.. I will update the documentation and add the warning

I did start on putting data into the key, but then started to worry about race conditions if I had to first read and then act on that. Here we dont use the atLeastFor feature at all, and only use this for ensuring some physical devices only receives commands from one process at a time

NATS 2.11 should be close,.. still claims to be coming in 2024

[lukas-krecan]

Thanks a lot, how urgently do you need it? Does it make sense to wait few weeks for 2.11?

[Saphri]

I'm not confident that NATS will release 2.11 this year... not even an RC/Beta have been seen

Internally we have a lib with this code that we just import, so we have no urgent need. We just wanted to give back 😸

[lukas-krecan]

Hi, I appreciate it. I prefer to keep the PR open and wait for the 2.11. The reason is that if they indeed deliver more fine-grained TTLs, the move from the current solution to the new one would be backwards incompatible, so I would have to keep both versions for some time. Thanks for understanding. Can you please ping me if there are any updates?