Slick.Caching

Documentation

simpleJsonCache :: ShakeValue q => q -> Action Value -> Rules (Action Value)

A wrapper around jsonCache which simplifies caching of values which do NOT depend on an input parameter. Unfortunately Shake still requires that the key type implement several typeclasses, however this is easily accomplished using GeneralizedNewtypeDeriving and a wrapper around (). example usage:

{-# LANGUAGE GeneralizedNewtypeDeriving #-}
module Main where
newtype ProjectList = ProjectList ()
  deriving (Show, Eq, Hashable, Binary, NFData)

Within your shake Rules:

projectCache = simpleJsonCache (ProjectList ()) $ do
  -- load your project list here; returning it as a Value

simpleJsonCache' :: forall q a. (ToJSON a, FromJSON a, ShakeValue q) => q -> Action a -> Rules (Action a)

Like simpleJsonCache but allows caching any JSON serializable object.

jsonCache :: ShakeValue q => (q -> Action Value) -> Rules (q -> Action Value)

A wrapper around addOracleCache which given a q which is a ShakeValue allows caching and retrieving Values within Shake. See documentation on addOracleCache or see Slick examples for more info.

-- We need to define a unique datatype as our cache key
newtype PostFilePath =
  PostFilePath String
-- We can derive the classes we need (using GeneralizedNewtypeDeriving) 
-- so long as the underlying type implements them
  deriving (Show, Eq, Hashable, Binary, NFData)
-- now in our shake rules we can create a cache by providing a loader action

do
postCache <- jsonCache $ \(PostFilePath path) ->
  readFile' path >>= markdownToHTML . Text.pack
-- Now use postCache inside an Action to load your post with caching!

jsonCache' :: forall a q. (ToJSON a, FromJSON a, ShakeValue q) => (q -> Action a) -> Rules (q -> Action a)

Like jsonCache but allows caching/retrieving any JSON serializable objects.