Implement token return for the token bucket rate limiting strategy

[kas1337]

The current implementation for the token bucket ("smooth") rate limiting strategy does not support token return. The idea is that the bucket is not only filled periodically with a defined amount of token but also that a token is placed back into the bucket when a request is finished.

It would be nice if there is a rate limit option that you can enable or disable.

[Ladicek]

Could you please point me to some materials that I can read to learn more about token bucket rate limiting with token return? I admit my rate limiting knowledge is rather limited, but I don't recall seeing token return mentioned in the articles I read.

[mschorsch]

bucket4j supports this feature (see hier).

[Ladicek]

Bucket4j is a much more complete and advanced and feature-full implementation of token bucket than SmallRye Fault Tolerance will likely ever have. If you need that, I see nothing wrong with using Bucket4j.

That said, how would you imagine token return would work in SmallRye Fault Tolerance? Can you show an example or two of code you'd like to write and add a comment about their meaning?

I see there would probably need to be more config options for token bucket than the other algorithms (for example, the initial token count is currently hardcoded). So I'm thinking maybe a 2nd annotation specific to the smooth rate limiter would be in order -- the @RateLimit annotation is pretty overcrowded already.