[FEATURE-REQUEST] HTTP cache - RFC compliant with many other features

[darkweak]

Hello,

I already wrote an HTTP cache system (called Souin) used by the caddy cache-handler module and roadrunner, compatible with Træfik, Tyk and many other reverse-proxies/API Gateway. It supports the RFC-7234, can partially cache graphQL request, invalidate using xkeys/ykeys like Varnish. It also implements the Fastly purge using the Surrogate-key header. It can store and invalidate a CDN (cloudflare, fastly, Akamai), and it supports the Cache-Status RFC directive. It implements two in-memory/fs storages (badger & nutsdb) and two distributed storages (olric & etcd) that are fully configurable. The keys can be tweaked (e.g. serve the same cached css for multiple domains) and we can change the Cache-Status name through the configuration and it support the ESI tags processing.

Let me know your preference about that.✌️