docs.txt

We are working on a package for caching data. The main type in the package is called "SmartCache". Here's it's description:

SmartCache:
- Contains an in-memory cache of type "*T". The T type is generic.
- Has a "primaryTTL" attribute
    - It describes a time after which the cache should be refreshed, but data can still be returned from cache
- Has a "secondaryTTL" attribute:
    - It describes a time after which the cache should be refreshed, and cache can't be used to return data
- Has a "cacheErrFunc" which is a function that given the error returns a ttl of the cache with error
    - if the function returns ttl > 0, function error should be returned from the cache for that period of time
- Has a "Get" method, that:
    - Accepts a context
    - Accepts a key
    - Accepts a fetch function
    - If there's no data in cache: calls fetch function, updates the cache and returns the result
    - If there's data in cache and primaryTTL is not expired: returns the cached data
    - If there's data in cache, primaryTTL is expired but secondaryTTL is not expired: returns the data from cache and does cache update in the background by calling fetch function
    - If there's data in cache and all TTLs are expired: works as if there's no data in cache
    - When called and a cache update for the same key is still running in the background, it should wait for the results in the cache