Safe Haskell	None
Language	Haskell2010

Database.Persist.Monad.Internal.SqlTransaction

Synopsis

newtype SqlTransaction (m :: Type -> Type) a = UnsafeSqlTransaction {
- unSqlTransaction :: ReaderT SqlTransactionEnv m a
}
data SqlTransactionEnv = SqlTransactionEnv {
- sqlBackend :: SqlBackend
- ignoreCatch :: SomeException -> Bool
}
runSqlTransaction :: MonadUnliftIO m => SqlTransactionEnv -> SqlTransaction m a -> m a
catchSqlTransaction :: forall (m :: Type -> Type) e a. (MonadUnliftIO m, Exception e) => SqlTransaction m a -> (e -> SqlTransaction m a) -> SqlTransaction m a

Documentation

newtype SqlTransaction (m :: Type -> Type) a Source #

The monad that tracks transaction state.

Conceptually equivalent to SqlPersistT, but restricts IO operations, for two reasons:

Forking a thread that uses the same SqlBackend as the current thread causes Bad Things to happen.
Transactions may need to be retried, in which case IO operations in a transaction are required to be rerunnable.

You shouldn't need to explicitly use this type; your functions should only declare the MonadSqlQuery constraint.

Constructors

UnsafeSqlTransaction
Fields unSqlTransaction :: ReaderT SqlTransactionEnv m a

Instances

Instances details

MonadRerunnableTrans SqlTransaction Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

rerunnableLift :: Monad m => m a -> SqlTransaction m a Source #

(TypeError ('Text "Cannot run arbitrary IO actions within a transaction. If the IO action is rerunnable, use rerunnableIO") :: Constraint, Monad m) => MonadIO (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

liftIO :: IO a -> SqlTransaction m a #

Applicative m => Applicative (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

pure :: a -> SqlTransaction m a #

(<*>) :: SqlTransaction m (a -> b) -> SqlTransaction m a -> SqlTransaction m b #

liftA2 :: (a -> b -> c) -> SqlTransaction m a -> SqlTransaction m b -> SqlTransaction m c #

(*>) :: SqlTransaction m a -> SqlTransaction m b -> SqlTransaction m b #

(<*) :: SqlTransaction m a -> SqlTransaction m b -> SqlTransaction m a #

Functor m => Functor (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

fmap :: (a -> b) -> SqlTransaction m a -> SqlTransaction m b #

(<$) :: a -> SqlTransaction m b -> SqlTransaction m a #

Monad m => Monad (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

(>>=) :: SqlTransaction m a -> (a -> SqlTransaction m b) -> SqlTransaction m b #

(>>) :: SqlTransaction m a -> SqlTransaction m b -> SqlTransaction m b #

return :: a -> SqlTransaction m a #

MonadFix m => MonadFix (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

mfix :: (a -> SqlTransaction m a) -> SqlTransaction m a #

MonadRerunnableIO m => MonadRerunnableIO (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Methods

rerunnableIO :: IO a -> SqlTransaction m a Source #

(MonadSqlQuery m, MonadUnliftIO m) => MonadSqlQuery (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

Associated Types

type TransactionM (SqlTransaction m)
Instance details Defined in Database.Persist.Monad.Internal.SqlTransaction type TransactionM (SqlTransaction m) = TransactionM m

Methods

runQueryRep :: Typeable record => SqlQueryRep record a -> SqlTransaction m a Source #

withTransaction :: TransactionM (SqlTransaction m) a -> SqlTransaction m a Source #

type TransactionM (SqlTransaction m) Source #

Instance details

Defined in Database.Persist.Monad.Internal.SqlTransaction

type TransactionM (SqlTransaction m) = TransactionM m

data SqlTransactionEnv Source #

Constructors

SqlTransactionEnv
Fields sqlBackend :: SqlBackend ignoreCatch :: SomeException -> Bool

runSqlTransaction :: MonadUnliftIO m => SqlTransactionEnv -> SqlTransaction m a -> m a Source #

catchSqlTransaction :: forall (m :: Type -> Type) e a. (MonadUnliftIO m, Exception e) => SqlTransaction m a -> (e -> SqlTransaction m a) -> SqlTransaction m a Source #

Like normal catch, except ignores errors specified by ignoreCatch.