Cache invalidation

[JunTaoLuo]

Currently we only set the absolute timeouts for cache entries. There is no mechanism to explicitly invalidate a cache entry before expiry. Also, how would applications/users interact with this feature?

Note that invalidation is required by the RFC for unsafe methods, e.g. a successful PUT should invalidate any previous cached resources at the same URI.

[refactorthis]

endpoints that mutate state should invalidate the previous cached item by default as you mention. It would also be beneficial to have the ability to inject a service that allows invalidating cached items on demand. For example an event received over a bus may mutate the objects state which would require invalidation. This may however be out of scope and better handled by abstracting the cache to a different layer?

[muratg]

@glennc If we want to do this in the future, we should get together and agree on a design.