Web.Sprinkles.Cache

Documentation

data Cache k v

Common interface for cache backends. In Cache k v, k is the key type and v the value type.

Constructors

Cache

Fields

• cacheGet :: k -> IO (Maybe v)

  Get Just the cached value or Nothing

• cachePut :: k -> v -> IO ()

  Insert an entry into the cache

• cacheDelete :: k -> IO ()

  Delete an entry from the cache

• cacheVacuum :: IO Int

  Delete all stale keys, return number of keys deleted

Instances

Semigroup (Cache k v)

Defined in Web.Sprinkles.Cache

Methods

(<>) :: Cache k v -> Cache k v -> Cache k v

sconcat :: NonEmpty (Cache k v) -> Cache k v

stimes :: Integral b => b -> Cache k v -> Cache k v

Monoid (Cache k v)

Defined in Web.Sprinkles.Cache

Methods

mempty :: Cache k v

mappend :: Cache k v -> Cache k v -> Cache k v

mconcat :: [Cache k v] -> Cache k v

cacheFetch :: (k -> IO v) -> Cache k v -> k -> IO v

cacheFetch load cache key fetches a value at the key from the cache, failing over to the load action when the key is not present in the cache, and adding it to the cache.

cached :: Cache k v -> (k -> IO v) -> k -> IO v

nullCache :: Cache k v

A cache that doesn't actually cache anything

appendCache :: Cache k v -> Cache k v -> Cache k v

transformCache :: (k -> j) -> (j -> Maybe k) -> (v -> IO (Maybe u)) -> (u -> IO (Maybe v)) -> Cache j u -> Cache k v

Wrap a cache such that the new cache uses different types for the keys and values, using the provided transformation functions. A typical application for this is to serialize data structures into a more palatable format for caching while exposing a more useful kind of data structure