Control.SafeAccess

Documentation

newtype Capability m d

Allow things to be accessed. See ensureAccess.

d is the type describing an access.

Constructors

MkCapability

Fields

• runCapability :: d -> m AccessDecision

Instances

Applicative m => Semigroup (Capability m d)

Defined in Control.SafeAccess

Methods

(<>) :: Capability m d -> Capability m d -> Capability m d

sconcat :: NonEmpty (Capability m d) -> Capability m d

stimes :: Integral b => b -> Capability m d -> Capability m d

Applicative m => Monoid (Capability m d)

Defined in Control.SafeAccess

Methods

mempty :: Capability m d

mappend :: Capability m d -> Capability m d -> Capability m d

mconcat :: [Capability m d] -> Capability m d

type Capabilities m d = [Capability m d]

data AccessDecision

Control the decision process.

The constructors are ordered by prevalence. For instance, if two capabilities respectively return AccessGranted and AccessDenied, the final decision will be AccessDenied.

Constructors

AccessDeniedSoft

No but another Capability can still decide to grant

AccessGranted

Final yes (see explanation)

AccessDenied

Final no

Instances

Eq AccessDecision

Defined in Control.SafeAccess

Methods

(==) :: AccessDecision -> AccessDecision -> Bool

(/=) :: AccessDecision -> AccessDecision -> Bool

Show AccessDecision

Defined in Control.SafeAccess

Methods

showsPrec :: Int -> AccessDecision -> ShowS

show :: AccessDecision -> String

showList :: [AccessDecision] -> ShowS

Semigroup AccessDecision

Defined in Control.SafeAccess

Methods

(<>) :: AccessDecision -> AccessDecision -> AccessDecision

sconcat :: NonEmpty AccessDecision -> AccessDecision

stimes :: Integral b => b -> AccessDecision -> AccessDecision

Monoid AccessDecision

Defined in Control.SafeAccess

Methods

mempty :: AccessDecision

mappend :: AccessDecision -> AccessDecision -> AccessDecision

mconcat :: [AccessDecision] -> AccessDecision

newtype SafeAccessT d m a

A simple monad transformer to ensure that data are accessed legitimately.

The return value is either the description of an access having been denied (left) or the result of the normal computation (right).

Constructors

SafeAccessT

Fields

• runSafeAccessT :: Capabilities m d -> m (Either d a)

Instances

MonadWriter w m => MonadWriter w (SafeAccessT d m)

Defined in Control.SafeAccess

Methods

writer :: (a, w) -> SafeAccessT d m a

tell :: w -> SafeAccessT d m ()

listen :: SafeAccessT d m a -> SafeAccessT d m (a, w)

pass :: SafeAccessT d m (a, w -> w) -> SafeAccessT d m a

MonadState s m => MonadState s (SafeAccessT d m)

Defined in Control.SafeAccess

Methods

get :: SafeAccessT d m s

put :: s -> SafeAccessT d m ()

state :: (s -> (a, s)) -> SafeAccessT d m a

MonadReader r m => MonadReader r (SafeAccessT d m)

Defined in Control.SafeAccess

Methods

ask :: SafeAccessT d m r

local :: (r -> r) -> SafeAccessT d m a -> SafeAccessT d m a

reader :: (r -> a) -> SafeAccessT d m a

MonadError e m => MonadError e (SafeAccessT d m)

Defined in Control.SafeAccess

Methods

throwError :: e -> SafeAccessT d m a

catchError :: SafeAccessT d m a -> (e -> SafeAccessT d m a) -> SafeAccessT d m a

Monad m => MonadSafeAccess d (SafeAccessT d m) m

Defined in Control.SafeAccess

Methods

getCapabilities :: SafeAccessT d m (Capabilities m d)

liftSub :: m a -> SafeAccessT d m a

denyAccess :: d -> SafeAccessT d m ()

catchAccessError :: SafeAccessT d m a -> (d -> SafeAccessT d m a) -> SafeAccessT d m a

MonadTrans (SafeAccessT d)

Defined in Control.SafeAccess

Methods

lift :: Monad m => m a -> SafeAccessT d m a

Monad m => Monad (SafeAccessT d m)

Defined in Control.SafeAccess

Methods

(>>=) :: SafeAccessT d m a -> (a -> SafeAccessT d m b) -> SafeAccessT d m b

(>>) :: SafeAccessT d m a -> SafeAccessT d m b -> SafeAccessT d m b

return :: a -> SafeAccessT d m a

fail :: String -> SafeAccessT d m a

Functor f => Functor (SafeAccessT d f)

Defined in Control.SafeAccess

Methods

fmap :: (a -> b) -> SafeAccessT d f a -> SafeAccessT d f b

(<$) :: a -> SafeAccessT d f b -> SafeAccessT d f a

Applicative f => Applicative (SafeAccessT d f)

Defined in Control.SafeAccess

Methods

pure :: a -> SafeAccessT d f a

(<*>) :: SafeAccessT d f (a -> b) -> SafeAccessT d f a -> SafeAccessT d f b

liftA2 :: (a -> b -> c) -> SafeAccessT d f a -> SafeAccessT d f b -> SafeAccessT d f c

(*>) :: SafeAccessT d f a -> SafeAccessT d f b -> SafeAccessT d f b

(<*) :: SafeAccessT d f a -> SafeAccessT d f b -> SafeAccessT d f a

MonadIO m => MonadIO (SafeAccessT d m)

Defined in Control.SafeAccess

Methods

liftIO :: IO a -> SafeAccessT d m a

class (Monad m, Monad s) => MonadSafeAccess d m s | m -> s, m -> d where

Methods

getCapabilities :: m (Capabilities s d)

liftSub :: s a -> m a

denyAccess :: d -> m ()

catchAccessError :: m a -> (d -> m a) -> m a

Catch an access error, i.e. an access descriptor which resulted into an access denied given the capabilities.

Instances

MonadSafeAccess d m s => MonadSafeAccess d (MaybeT m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: MaybeT m (Capabilities s d)

liftSub :: s a -> MaybeT m a

denyAccess :: d -> MaybeT m ()

catchAccessError :: MaybeT m a -> (d -> MaybeT m a) -> MaybeT m a

MonadSafeAccess d m s => MonadSafeAccess d (ListT m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: ListT m (Capabilities s d)

liftSub :: s a -> ListT m a

denyAccess :: d -> ListT m ()

catchAccessError :: ListT m a -> (d -> ListT m a) -> ListT m a

(MonadSafeAccess d m s, Monoid w) => MonadSafeAccess d (WriterT w m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: WriterT w m (Capabilities s d)

liftSub :: s a -> WriterT w m a

denyAccess :: d -> WriterT w m ()

catchAccessError :: WriterT w m a -> (d -> WriterT w m a) -> WriterT w m a

MonadSafeAccess d m s => MonadSafeAccess d (IdentityT m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: IdentityT m (Capabilities s d)

liftSub :: s a -> IdentityT m a

denyAccess :: d -> IdentityT m ()

catchAccessError :: IdentityT m a -> (d -> IdentityT m a) -> IdentityT m a

MonadSafeAccess d m s => MonadSafeAccess d (StateT s' m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: StateT s' m (Capabilities s d)

liftSub :: s a -> StateT s' m a

denyAccess :: d -> StateT s' m ()

catchAccessError :: StateT s' m a -> (d -> StateT s' m a) -> StateT s' m a

MonadSafeAccess d m s => MonadSafeAccess d (ExceptT e m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: ExceptT e m (Capabilities s d)

liftSub :: s a -> ExceptT e m a

denyAccess :: d -> ExceptT e m ()

catchAccessError :: ExceptT e m a -> (d -> ExceptT e m a) -> ExceptT e m a

Monad m => MonadSafeAccess d (SafeAccessT d m) m

Defined in Control.SafeAccess

Methods

getCapabilities :: SafeAccessT d m (Capabilities m d)

liftSub :: m a -> SafeAccessT d m a

denyAccess :: d -> SafeAccessT d m ()

catchAccessError :: SafeAccessT d m a -> (d -> SafeAccessT d m a) -> SafeAccessT d m a

MonadSafeAccess d m s => MonadSafeAccess d (ReaderT r m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: ReaderT r m (Capabilities s d)

liftSub :: s a -> ReaderT r m a

denyAccess :: d -> ReaderT r m ()

catchAccessError :: ReaderT r m a -> (d -> ReaderT r m a) -> ReaderT r m a

MonadSafeAccess d m s => MonadSafeAccess d (ContT e m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: ContT e m (Capabilities s d)

liftSub :: s a -> ContT e m a

denyAccess :: d -> ContT e m ()

catchAccessError :: ContT e m a -> (d -> ContT e m a) -> ContT e m a

(MonadSafeAccess d m s, Monoid w) => MonadSafeAccess d (RWST r w st m) s

Defined in Control.SafeAccess

Methods

getCapabilities :: RWST r w st m (Capabilities s d)

liftSub :: s a -> RWST r w st m a

denyAccess :: d -> RWST r w st m ()

catchAccessError :: RWST r w st m a -> (d -> RWST r w st m a) -> RWST r w st m a

ensureAccess :: MonadSafeAccess d m s => d -> m ()

Check that the access is legal or make the monad "fail".

unsecureAllow :: (Monad m, Eq d) => [d] -> SafeAccessT d m a -> SafeAccessT d m a

Allow certain accesses regardless of the capabilities. (unsecure!)

singleCapability :: (Applicative f, Eq d) => d -> Capability f d

Create a capability which only allows a given access

someCapabilities :: (Applicative f, Eq d) => [d] -> Capability f d

Create a capability which only allows given accesses

passthroughCapability :: Applicative f => Capability f d

A special capability which allows every access. Be careful with this!

liftExceptT :: ExceptT d m a -> SafeAccessT d m a

Lift an action from ErrorT to SafeAccessT.

liftCapability :: (Monad m, MonadTrans t) => Capability m d -> Capability (t m) d