module Database.Persist.GenericSql.Migration
( Migration
, parseMigration
, parseMigration'
, printMigration
, getMigration
, runMigration
, runMigrationSilent
, runMigrationUnsafe
, migrate
, commit
, rollback
) where
import Database.Persist.GenericSql.Internal
import Database.Persist.EntityDef
import qualified Database.Persist.GenericSql.Raw as R
import Database.Persist.Store
import Database.Persist.GenericSql.Raw (SqlPersist (..))
#if MIN_VERSION_monad_control(0, 3, 0)
import Control.Monad.Trans.Control (MonadBaseControl)
#define MBCIO MonadBaseControl IO
#else
import Control.Monad.IO.Control (MonadControlIO)
#define MBCIO MonadControlIO
#endif
import Control.Monad.Trans.Class (MonadTrans (..))
import Control.Monad.IO.Class
import Control.Monad.Trans.Reader
import Control.Monad.Trans.Writer
import Control.Monad (liftM, unless)
import Data.Text (Text, unpack, snoc, isPrefixOf, pack)
import qualified Data.Text.IO
import System.IO
import Control.Monad.Logger (MonadLogger)
import System.IO.Silently (hSilence)
import System.IO (stderr)
import Control.Monad.Trans.Control (liftBaseOp_)
execute' :: (MonadIO m, MonadLogger m) => Text -> [PersistValue] -> SqlPersist m ()
execute' = R.execute
type Sql = Text
type CautiousMigration = [(Bool, Sql)]
allSql :: CautiousMigration -> [Sql]
allSql = map snd
unsafeSql :: CautiousMigration -> [Sql]
unsafeSql = allSql . filter fst
safeSql :: CautiousMigration -> [Sql]
safeSql = allSql . filter (not . fst)
type Migration m = WriterT [Text] (WriterT CautiousMigration m) ()
parseMigration :: Monad m => Migration m -> m (Either [Text] CautiousMigration)
parseMigration =
liftM go . runWriterT . execWriterT
where
go ([], sql) = Right sql
go (errs, _) = Left errs
parseMigration' :: Monad m => Migration m -> m (CautiousMigration)
parseMigration' m = do
x <- parseMigration m
case x of
Left errs -> error $ unlines $ map unpack errs
Right sql -> return sql
printMigration :: (MBCIO m, MonadIO m) => Migration (SqlPersist m) -> SqlPersist m ()
printMigration m = do
mig <- parseMigration' m
mapM_ (liftIO . Data.Text.IO.putStrLn . flip snoc ';') (allSql mig)
getMigration :: (MBCIO m, MonadIO m) => Migration (SqlPersist m) -> SqlPersist m [Sql]
getMigration m = do
mig <- parseMigration' m
return $ allSql mig
runMigration :: (MonadIO m, MBCIO m, MonadLogger m)
=> Migration (SqlPersist m)
-> SqlPersist m ()
runMigration m = runMigration' m False >> return ()
runMigrationSilent :: (MBCIO m, MonadIO m, MonadLogger m)
=> Migration (SqlPersist m)
-> SqlPersist m [Text]
runMigrationSilent m = liftBaseOp_ (hSilence [stderr]) $ runMigration' m True
runMigration'
:: (MBCIO m, MonadIO m, MonadLogger m)
=> Migration (SqlPersist m)
-> Bool
-> SqlPersist m [Text]
runMigration' m silent = do
mig <- parseMigration' m
case unsafeSql mig of
[] -> mapM (executeMigrate silent) $ sortMigrations $ safeSql mig
errs -> error $ concat
[ "\n\nDatabase migration: manual intervention required.\n"
, "The following actions are considered unsafe:\n\n"
, unlines $ map (\s -> " " ++ unpack s ++ ";") $ errs
]
runMigrationUnsafe :: (MBCIO m, MonadIO m, MonadLogger m)
=> Migration (SqlPersist m)
-> SqlPersist m ()
runMigrationUnsafe m = do
mig <- parseMigration' m
mapM_ (executeMigrate False) $ sortMigrations $ allSql mig
executeMigrate :: (MonadIO m, MonadLogger m) => Bool -> Text -> SqlPersist m Text
executeMigrate silent s = do
unless silent $ liftIO $ hPutStrLn stderr $ "Migrating: " ++ unpack s
execute' s []
return s
sortMigrations :: [Sql] -> [Sql]
sortMigrations x =
filter isCreate x ++ filter (not . isCreate) x
where
isCreate t = pack "CREATe " `isPrefixOf` t
migrate :: (MonadIO m, MBCIO m, PersistEntity val)
=> [EntityDef]
-> val
-> Migration (SqlPersist m)
migrate allDefs val = do
conn <- lift $ lift $ SqlPersist ask
let getter = R.getStmt' conn
res <- liftIO $ migrateSql conn allDefs getter val
either tell (lift . tell) res
commit :: MonadIO m => SqlPersist m ()
commit = do
conn <- SqlPersist ask
let getter = R.getStmt' conn
liftIO $ commitC conn getter >> begin conn getter
rollback :: MonadIO m => SqlPersist m ()
rollback = do
conn <- SqlPersist ask
let getter = R.getStmt' conn
liftIO $ rollbackC conn getter >> begin conn getter