Add support to store JWT Token key/value pair in Redis cache

[jmiddleton]

The PoC implementation to use opaque tokens doesn't scale when you have multiple nginx servers in a HA solution. It would be good to have an option to use an external distributed cache like Redis or Memcached

[lcrilly]

We plan to address this by having the NGINX Plus native key-value store synchronize across a HA cluster in a future release.

[jmiddleton]

I heard about that, that's good to me. Is it part of the plan to support TTL on entries?
I'm thinking if the entries will be removed from the cache once expired. If so, the opaque token PoC should work well if tokens are removed from the cache.

[lcrilly]

NGINX Plus R16 supports opaque tokens with the key-value store. The PoC solution for opaque_session_tokens has been upgraded and is now suitable for production use. Tokens are removed from the key-value store on a configurable TTL.