Removed invalidParams

Yesod/Handler.hs

@@ -86,8 +86,6 @@ instance Exception e => Failure e (Handler yesod) where
 instance RequestReader (Handler yesod) where
     getRawRequest = Handler $ \(HandlerData rr _)
                         -> return ([], HCContent rr)
-    invalidParams = invalidArgs . map helper where
-        helper ((_pt, pn, _pvs), e) = (pn, show e)
 
 getYesod :: Handler yesod yesod
 getYesod = Handler $ \(HandlerData _ yesod) -> return ([], HCContent yesod)
@@ -153,7 +151,7 @@ notFound = errorResponse NotFound
 permissionDenied :: Handler yesod a
 permissionDenied = errorResponse PermissionDenied
 
-invalidArgs :: [(ParamName, ParamValue)] -> Handler yesod a
+invalidArgs :: [(ParamName, String)] -> Handler yesod a
 invalidArgs = errorResponse . InvalidArgs
 
 ------- Headers

Yesod/Helpers/Auth.hs

@@ -34,7 +34,7 @@ import qualified Data.ByteString.Char8 as B8
 import Data.Maybe (fromMaybe)
 import qualified Network.Wai
 import Data.Typeable (Typeable)
-import Control.Exception (Exception, SomeException (..))
+import Control.Exception (Exception)
 
 class YesodApproot a => YesodAuth a where
     -- | The following breaks DRY, but I cannot think of a better solution
@@ -91,26 +91,10 @@ instance ConvertSuccess OIDFormReq Html where
     convertSuccess (OIDFormReq (Just s) _) =
         Tag "p" [("class", "message")] $ cs s
 
-someParam :: (Monad m, RequestReader m)
-          => ParamType
-          -> (RawRequest -> ParamName -> [ParamValue])
-          -> ParamName
-          -> m ParamValue
-someParam pt paramList pn = do
-    rr <- getRawRequest
-    case paramList rr pn of
-        [x] -> return x
-        x -> invalidParams [((pt, pn, x), SomeException ExpectedSingleParam)]
-
 data ExpectedSingleParam = ExpectedSingleParam
     deriving (Show, Typeable)
 instance Exception ExpectedSingleParam
 
-getParam :: (Monad m, RequestReader m)
-         => ParamName
-         -> m ParamValue
-getParam = someParam GetParam getParams
-
 authOpenidForm :: Yesod y => Handler y ChooseRep
 authOpenidForm = do
     rr <- getRawRequest
@@ -134,7 +118,10 @@ authOpenidForm = do
 
 authOpenidForward :: YesodAuth y => Handler y ()
 authOpenidForward = do
-    oid <- getParam "openid"
+    rr <- getRawRequest
+    oid <- case getParams rr "openid" of
+            [x] -> return x
+            _ -> invalidArgs [("openid", show ExpectedSingleParam)]
     authroot <- getFullAuthRoot
     let complete = authroot ++ "/openid/complete/"
     res <- runAttemptT $ OpenId.getForwardUrl oid complete

Yesod/Request.hs

@@ -32,7 +32,6 @@ module Yesod.Request
     , ParamType (..)
     , ParamName
     , ParamValue
-    , ParamException
 #if TEST
     , testSuite
 #endif
@@ -47,7 +46,6 @@ import qualified Data.ByteString as B
 import qualified Data.ByteString.Lazy as BL
 import Data.Convertible.Text
 import Control.Arrow ((***))
-import Control.Exception (SomeException (..))
 import Data.Maybe (fromMaybe)
 import "transformers" Control.Monad.Trans
 import Control.Concurrent.MVar
@@ -61,11 +59,11 @@ import Test.Framework (testGroup, Test)
 data ParamType = GetParam | PostParam
 type ParamName = String
 type ParamValue = String
-type ParamException = [((ParamType, ParamName, [ParamValue]), SomeException)]
 
 class RequestReader m where
     getRawRequest :: m RawRequest
-    invalidParams :: ParamException -> m a
+instance RequestReader ((->) RawRequest) where
+    getRawRequest = id
 
 languages :: (Functor m, RequestReader m) => m [Language]
 languages = rawLangs `fmap` getRawRequest

Yesod/Response.hs

@@ -192,7 +192,7 @@ data SpecialResponse =
 data ErrorResponse =
       NotFound
     | InternalError String
-    | InvalidArgs [(String, String)]
+    | InvalidArgs [(String, String)] -- FIXME use SomeException?
     | PermissionDenied
     deriving (Show, Eq)