module Database.Persist.GenericSql.Raw
( withStmt
, execute
, SqlPersist (..)
, getStmt'
, getStmt
) where
import qualified Database.Persist.GenericSql.Internal as I
import Database.Persist.GenericSql.Internal hiding (execute, withStmt)
import Database.Persist.Base (PersistValue)
import Data.IORef
import Control.Monad.IO.Class
import Control.Monad.Trans.Reader
import qualified Data.Map as Map
import Control.Applicative (Applicative)
import Control.Monad.Trans.Class (MonadTrans (..))
import "MonadCatchIO-transformers" Control.Monad.CatchIO
newtype SqlPersist m a = SqlPersist (ReaderT Connection m a)
deriving (Monad, MonadIO, MonadCatchIO, MonadTrans, Functor, Applicative)
withStmt :: MonadCatchIO m => String -> [PersistValue]
-> (RowPopper (SqlPersist m) -> SqlPersist m a) -> SqlPersist m a
withStmt sql vals pop = do
stmt <- getStmt sql
ret <- I.withStmt stmt vals pop
liftIO $ reset stmt
return ret
execute :: MonadIO m => String -> [PersistValue] -> SqlPersist m ()
execute sql vals = do
stmt <- getStmt sql
liftIO $ I.execute stmt vals
liftIO $ reset stmt
getStmt :: MonadIO m => String -> SqlPersist m Statement
getStmt sql = do
conn <- SqlPersist ask
liftIO $ getStmt' conn sql
getStmt' :: Connection -> String -> IO Statement
getStmt' conn sql = do
smap <- liftIO $ readIORef $ stmtMap conn
case Map.lookup sql smap of
Just stmt -> return stmt
Nothing -> do
stmt <- liftIO $ prepare conn sql
liftIO $ writeIORef (stmtMap conn) $ Map.insert sql stmt smap
return stmt