Remote KV caching

[fkorotkov]

It might worth to add a similar to Makisu feature of using a Key-Value remote cache for caching layers. It can provide a more fine grain permission control for users than using a standard Docker registry for caching layers via --cache-repo flag.

Maybe add --cache-url flag to specify a url that exposes an HTTP cache. For instance, it can use the same protocol as Bazel is using: simple PUT/GET.

[bobcatfish]

Sounds like a cool feature to add! :D

[fkorotkov]

Bumping the issue since more and more tools are support such HTTP caches including GitHub Actions, Please Build, etc. IMO it will be a great option to have just a separate HTTP cache instead of an actual repository.

[Shaked]

This would be nice both with HTTP and Redis, same as Makisu does