handle ActionError prior to a user-defined handler (fixes #330)

Web/Scotty.hs

@@ -56,7 +56,7 @@
 import Network.Wai.Handler.Warp (Port)
 
 import Web.Scotty.Internal.Types (ScottyT, ActionT, ErrorHandler, Param, RoutePattern, Options, defaultOptions, File, Kilobytes, ScottyState, defaultScottyState, StatusError(..), Content(..))
-import Web.Scotty.Exceptions (Handler(..))
+import UnliftIO.Exception (Handler(..))
 
 type ScottyM = ScottyT IO
 type ActionM = ActionT IO
@@ -221,7 +221,7 @@
 --   This means captures are somewhat typed, in that a route won't match if a correctly typed
 --   capture cannot be parsed.
 param :: Trans.Parsable a => Text -> ActionM a
 param = Trans.param
 {-# DEPRECATED param "(#204) Not a good idea to treat all parameters identically. Use captureParam, formParam and queryParam instead. "#-}
 
 -- | Get a capture parameter.
@@ -285,7 +285,7 @@
 
 -- | Get all parameters from capture, form and query (in that order).
 params :: ActionM [Param]
 params = Trans.params
 {-# DEPRECATED params "(#204) Not a good idea to treat all parameters identically. Use captureParams, formParams and queryParams instead. "#-}
 
 -- | Get capture parameters

Web/Scotty/Action.hs

@@ -69,6 +69,7 @@ import qualified Data.ByteString.Char8      as B
 import qualified Data.ByteString.Lazy.Char8 as BL
 import qualified Data.CaseInsensitive       as CI
 import           Data.Int
+import           Data.Maybe                 (maybeToList)
 import qualified Data.Text                  as ST
 import qualified Data.Text.Encoding         as STE
 import qualified Data.Text.Lazy             as T
@@ -86,7 +87,7 @@ import           Numeric.Natural
 
 import           Web.Scotty.Internal.Types
 import           Web.Scotty.Util (mkResponse, addIfNotPresent, add, replace, lazyTextToStrictByteString, strictByteStringToLazyText)
-import Web.Scotty.Exceptions (Handler(..), catch, catchesOptionally, tryAny)
+import UnliftIO.Exception (Handler(..), catch, catches, tryAny)
 
 import Network.Wai.Internal (ResponseReceived(..))
 
@@ -101,13 +102,11 @@ runAction :: MonadUnliftIO m =>
           -> ActionT m () -- ^ Route action to be evaluated
           -> m (Maybe Response)
 runAction mh env action = do
-  let
-    handlers = [
-      statusErrorHandler, -- StatusError
-      actionErrorHandler, -- ActionError i.e. Next, Finish, Redirect
-      someExceptionHandler -- all remaining exceptions
-               ]
-  ok <- flip runReaderT env $ runAM $ tryNext (catchesOptionally action mh handlers )
+  ok <- flip runReaderT env $ runAM $ tryNext $ action `catches` concat
+    [ [actionErrorHandler]
+    , maybeToList mh
+    , [statusErrorHandler, someExceptionHandler]
+    ]
   res <- getResponse env
   return $ bool Nothing (Just $ mkResponse res) ok
 

Web/Scotty/Internal/Types.hs

@@ -41,7 +41,7 @@ import qualified Network.Wai as Wai
 import           Network.Wai.Handler.Warp (Settings, defaultSettings)
 import           Network.Wai.Parse (FileInfo)
 
-import Web.Scotty.Exceptions (Handler(..), catch, catches)
+import UnliftIO.Exception (Handler(..), catch, catches)
 
 
 --------------------- Options -----------------------

Web/Scotty/Trans.hs

@@ -66,7 +66,7 @@ import Web.Scotty.Route
 import Web.Scotty.Internal.Types (ActionT(..), ScottyT(..), defaultScottyState, Application, RoutePattern, Options(..), defaultOptions, RouteOptions(..), defaultRouteOptions, ErrorHandler, Kilobytes, File, addMiddleware, setHandler, updateMaxRequestBodySize, routes, middlewares, ScottyException(..), ScottyState, defaultScottyState, StatusError(..), Content(..))
 import Web.Scotty.Util (socketDescription)
 import Web.Scotty.Body (newBodyInfo)
-import Web.Scotty.Exceptions (Handler(..), catches)
+import UnliftIO.Exception (Handler(..), catches)
 
 -- | Run a scotty application using the warp server.
 -- NB: scotty p === scottyT p id

scotty.cabal

@@ -64,7 +64,6 @@ Library
                        Web.Scotty.Cookie
   other-modules:       Web.Scotty.Action
                        Web.Scotty.Body
-                       Web.Scotty.Exceptions
                        Web.Scotty.Route
                        Web.Scotty.Util
   default-language:    Haskell2010