Add ability to configure retries for RestClient

[altro3]

Improvement:

RestClient it's a good alternative for WebClient now, but for some reason, you lost a very important mechanism that WebClient has - the ability to configure retry attempts for sending requests.

It would be great if you added the ability to configure retry attempts in the rest client, because currently this requires the spring-retry library or a custom implementation.

I want to say that it would be cool to set up retry right at the RestClient creation level, as is done in WebClient

[bclozel]

Hello @altro3

I'm not sure we can introduce a retry operator directly in RestClient, because in the case of WebClient, this is directly supported by the reactor project. The good news is, in the meantime, spring-retry has been reworked and moved to Spring Framework. For an imperative programming model, the new resilience annotations make a lot of sense.

Can you have a look at the new resilience features and let us know?

[altro3]

Yes, I understand the reason. I realized this when I tried to configure it myself using a low-level Netty client.

Basically, the current problem is that I'm forced to use an aspect, but I'd like to push the settings to the programmatic level and use them from the bean's ConfigurationProperties. With a spec, I can only write expressions. This works, but it's inconvenient.

Judging by the documentation you shared, programmatically setting the RetryTemplate is what I need.

[bclozel]

Thanks for the feedback!