Database.Groundhog.Generic

This helper module is intended for use by the backend creators

Migration

createMigration :: PersistBackend m => Migration m -> m NamedMigrations

Produce the migrations but not execute them. Fails when an unsafe migration occurs.

executeMigration :: (PersistBackend m, MonadIO m) => (String -> IO ()) -> NamedMigrations -> m ()

Execute the migrations and log them.

executeMigrationUnsafe :: (PersistBackend m, MonadIO m) => (String -> IO ()) -> NamedMigrations -> m ()

Execute migrations and log them. Executes the unsafe migrations without warnings

runMigration :: (PersistBackend m, MonadIO m) => (String -> IO ()) -> Migration m -> m ()

Run migrations and log them. Fails when an unsafe migration occurs.

runMigrationUnsafe :: (PersistBackend m, MonadIO m) => (String -> IO ()) -> Migration m -> m ()

Run migrations and log them. Executes the unsafe migrations without warnings

printMigration :: MonadIO m => NamedMigrations -> m ()

Pretty print the migrations

mergeMigrations :: [SingleMigration] -> SingleMigration

Joins the migrations. The result is either all error messages or all queries

silentMigrationLogger :: String -> IO ()

No-op

defaultMigrationLogger :: String -> IO ()

Prints the queries to stdout

failMessage :: PersistField a => a -> [PersistValue] -> String

Helper functions defining *PersistValue instances

primToPersistValue :: (PersistBackend m, PrimitivePersistField a) => a -> m ([PersistValue] -> [PersistValue])

primFromPersistValue :: (PersistBackend m, PrimitivePersistField a) => [PersistValue] -> m (a, [PersistValue])

pureToPersistValue :: (PersistBackend m, PurePersistField a) => a -> m ([PersistValue] -> [PersistValue])

pureFromPersistValue :: (PersistBackend m, PurePersistField a) => [PersistValue] -> m (a, [PersistValue])

singleToPersistValue :: (PersistBackend m, SinglePersistField a) => a -> m ([PersistValue] -> [PersistValue])

singleFromPersistValue :: (PersistBackend m, SinglePersistField a) => [PersistValue] -> m (a, [PersistValue])

toSinglePersistValueUnique :: forall m v u. (PersistBackend m, PersistEntity v, IsUniqueKey (Key v (Unique u)), PrimitivePersistField (Key v (Unique u))) => u (UniqueMarker v) -> v -> m PersistValue

fromSinglePersistValueUnique :: forall m v u. (PersistBackend m, PersistEntity v, IsUniqueKey (Key v (Unique u)), PrimitivePersistField (Key v (Unique u))) => u (UniqueMarker v) -> PersistValue -> m v

toPersistValuesUnique :: forall m v u. (PersistBackend m, PersistEntity v, IsUniqueKey (Key v (Unique u))) => u (UniqueMarker v) -> v -> m ([PersistValue] -> [PersistValue])

fromPersistValuesUnique :: forall m v u. (PersistBackend m, PersistEntity v, IsUniqueKey (Key v (Unique u))) => u (UniqueMarker v) -> [PersistValue] -> m (v, [PersistValue])

toSinglePersistValueAutoKey :: forall m v. (PersistBackend m, PersistEntity v, PrimitivePersistField (AutoKey v)) => v -> m PersistValue

fromSinglePersistValueAutoKey :: forall m v. (PersistBackend m, PersistEntity v, PrimitivePersistField (Key v BackendSpecific)) => PersistValue -> m v

Other

bracket

Arguments

:: MonadBaseControl IO m

=> m a

computation to run first (acquire resource)

-> (a -> m b)

computation to run last (release resource)

-> (a -> m c)

computation to run in-between

-> m c

finally

Arguments

:: MonadBaseControl IO m

=> m a

computation to run first

-> m b

computation to run afterward (even if an exception was raised)

-> m a

onException :: MonadBaseControl IO m => m a -> m b -> m a

data PSEmbeddedFieldDef

Constructors

PSEmbeddedFieldDef

Fields

psEmbeddedFieldName :: String

psDbEmbeddedFieldName :: Maybe String

psSubEmbedded :: Maybe [PSEmbeddedFieldDef]

Instances

Show PSEmbeddedFieldDef

applyEmbeddedDbTypeSettings :: [PSEmbeddedFieldDef] -> DbType -> DbType

findOne :: (Eq c, Show c) => String -> (a -> c) -> (b -> c) -> a -> [b] -> b

replaceOne :: (Eq c, Show c) => String -> (a -> c) -> (b -> c) -> (a -> b -> b) -> a -> [b] -> [b]

matchElements :: Show a => (a -> b -> Bool) -> [a] -> [b] -> ([a], [b], [(a, b)])

Returns only old elements, only new elements, and matched pairs (old, new). The new ones exist only in datatype, the old are present only in DB, match is typically by name (the properties of the matched elements may differ).

haveSameElems :: Show a => (a -> b -> Bool) -> [a] -> [b] -> Bool

mapAllRows :: Monad m => ([PersistValue] -> m a) -> RowPopper m -> m [a]

phantomDb :: PersistBackend m => m (Proxy (PhantomDb m))

isSimple :: [ConstructorDef] -> Bool