Data.Text interface to hedis (Redis)

Redis.hs

{-# LANGUAGE NoMonomorphismRestriction, OverloadedStrings #-}
module Backend.Redis (connect, get, set, R.Connection) where

import Control.Monad.IO.Class
import qualified Database.Redis as R
import Control.Applicative

import qualified Data.Text.Lazy as L
import qualified Data.Text.Lazy.Encoding as L
import qualified Data.Text.Encoding as T

import qualified Data.ByteString.Char8 as BS

-- :(
fromStrict :: BS.ByteString -> L.Text
fromStrict = L.fromStrict . T.decodeUtf8

toStrict :: L.Text -> BS.ByteString
toStrict = T.encodeUtf8 . L.toStrict

connect = liftIO $ R.connect R.defaultConnectInfo

set :: (MonadIO m) => R.Connection -> L.Text -> L.Text -> m Bool
set redis idx val = liftIO $ R.runRedis redis $ do
                      c <- R.set (toStrict idx) (toStrict val)
                      case c of
                        Right _ -> return True
                        Left _ -> return False

-- TODO: monad error insteadf of L.Text
get :: (MonadIO m) => R.Connection -> L.Text -> m (Either L.Text (Maybe L.Text))
get redis idx = liftIO $ R.runRedis redis $ do
                  c <- R.get (toStrict idx)
                  case c of
                    Right u -> return $ Right $ fromStrict <$> u
                    Left _ -> return $ Left "DatabaseError"