module Yesod.Persist
( YesodPersist (..)
, YesodDB
, get404
, getBy404
, module Database.Persist
, module Database.Persist.TH
) where
import Database.Persist
import Database.Persist.TH
import Control.Monad.Trans.Class (MonadTrans)
import Yesod.Handler
type YesodDB sub master = YesodPersistBackend master (GHandler sub master)
class YesodPersist master where
type YesodPersistBackend master :: (* -> *) -> * -> *
runDB :: YesodDB sub master a -> GHandler sub master a
get404 :: ( PersistStore b m
, PersistEntity val
, Monad (b m)
, m ~ GHandler sub master
, MonadTrans b
)
=> Key b val -> b m val
get404 key = do
mres <- get key
case mres of
Nothing -> lift notFound
Just res -> return res
getBy404 :: ( PersistUnique b m
, PersistEntity val
, m ~ GHandler sub master
, Monad (b m)
, MonadTrans b
, PersistEntityBackend val ~ b
)
=> Unique val b -> b m (Entity val)
getBy404 key = do
mres <- getBy key
case mres of
Nothing -> lift notFound
Just res -> return res