--- #prune
+{-# OPTIONS_HADDOCK prune #-}
--- | Aborting the computation of 'Network.HTTP.Lucu.Resource.Resource'
--- in any IO monads or arrows.
+-- |Aborting the computation of 'Network.HTTP.Lucu.Resource.Resource'
+-- in any 'Prelude.IO' monads or arrows.
module Network.HTTP.Lucu.Abortion
( Abortion(..)
, abort
+ , abortPurely
, abortSTM
, abortA
, abortPage
import Control.Concurrent.STM
import Control.Exception
import Control.Monad.Trans
-import GHC.Conc (unsafeIOToSTM)
+import qualified Data.ByteString.Char8 as C8
import Data.Dynamic
+import GHC.Conc (unsafeIOToSTM)
import Network.HTTP.Lucu.Config
import Network.HTTP.Lucu.DefaultPage
import Network.HTTP.Lucu.Headers
-import Network.HTTP.Lucu.HttpVersion
import Network.HTTP.Lucu.Request
import Network.HTTP.Lucu.Response
import System.IO.Unsafe
data Abortion = Abortion {
- aboStatus :: StatusCode
- , aboHeaders :: Headers
- , aboMessage :: Maybe String
+ aboStatus :: !StatusCode
+ , aboHeaders :: !Headers
+ , aboMessage :: !(Maybe String)
} deriving (Show, Typeable)
--- | Computation of @'abort' status headers msg@ aborts the
+instance Exception Abortion
+
+-- |Computation of @'abort' status headers msg@ aborts the
-- 'Network.HTTP.Lucu.Resource.Resource' monad with given status,
-- additional response headers, and optional message string.
--
--- What this really does is to just throw a special DynException. The
--- exception will be caught by the system.
+-- What this really does is to throw a special
+-- 'Control.Exception.Exception'. The exception will be caught by the
+-- Lucu system.
--
-- 1. If the 'Network.HTTP.Lucu.Resource.Resource' is in the /Deciding
-- Header/ or any precedent states, it is possible to use the
-- > (Just "It has been moved to example.net")
abort :: MonadIO m => StatusCode -> [ (String, String) ] -> Maybe String -> m a
abort status headers msg
- = let abo = Abortion status headers msg
- exc = DynException (toDyn abo)
+ = status `seq` headers `seq` msg `seq`
+ let abo = Abortion status (toHeaders $ map pack headers) msg
in
- liftIO $ throwIO exc
+ liftIO $ throwIO abo
+ where
+ pack (x, y) = (C8.pack x, C8.pack y)
+
+-- |This is similar to 'abort' but computes it with
+-- 'System.IO.Unsafe.unsafePerformIO'.
+abortPurely :: StatusCode -> [ (String, String) ] -> Maybe String -> a
+abortPurely = ((unsafePerformIO .) .) . abort
--- | Computation of @'abortSTM' status headers msg@ just computes
--- 'abort' in a STM monad.
+-- |Computation of @'abortSTM' status headers msg@ just computes
+-- 'abort' in a 'Control.Monad.STM.STM' monad.
abortSTM :: StatusCode -> [ (String, String) ] -> Maybe String -> STM a
abortSTM status headers msg
- = unsafeIOToSTM $ abort status headers msg
+ = status `seq` headers `seq` msg `seq`
+ unsafeIOToSTM $! abort status headers msg
-- | Computation of @'abortA' -< (status, (headers, msg))@ just
--- computes 'abort' in an ArrowIO.
+-- computes 'abort' in an 'Control.Arrow.ArrowIO.ArrowIO'.
abortA :: ArrowIO a => a (StatusCode, ([ (String, String) ], Maybe String)) c
abortA
= arrIO3 abort
-
-- aboMessage が Just なら單に mkDefaultPage に渡すだけで良いので樂だが、
-- Nothing の場合は getDefaultPage を使ってデフォルトのメッセージを得な
-- ければならない。
abortPage :: Config -> Maybe Request -> Response -> Abortion -> String
abortPage conf reqM res abo
- = case aboMessage abo of
+ = conf `seq` reqM `seq` res `seq` abo `seq`
+ case aboMessage abo of
Just msg
-> let [html] = unsafePerformIO
$ runX ( mkDefaultPage conf (aboStatus abo) (txt msg)
Nothing
-> let res' = res { resStatus = aboStatus abo }
res'' = foldl (.) id [setHeader name value
- | (name, value) <- aboHeaders abo]
- $ res'
+ | (name, value) <- fromHeaders $ aboHeaders abo] res'
in
getDefaultPage conf reqM res''