yesod/Yesod/Yesod.hs
2009-12-13 09:50:43 +02:00

88 lines
2.7 KiB
Haskell

-- | The basic typeclass for a Yesod application.
module Yesod.Yesod
( Yesod (..)
, toHackApp
) where
import Yesod.Rep
import Data.Object.Html (toHtmlObject)
import Yesod.Response
import Yesod.Request
import Yesod.Constants
import Yesod.Definitions
import Yesod.Resource
import Yesod.Handler
--import Control.Monad (when)
import qualified Hack
import Hack.Middleware.CleanPath
import Hack.Middleware.ClientSession
import Hack.Middleware.Gzip
import Hack.Middleware.Jsonp
import Hack.Middleware.MethodOverride
type ContentPair = (ContentType, Content)
class Yesod a where
handlers ::
[(ResourcePatternString,
[(Verb, [ContentType] -> Handler a ContentPair)])]
-- | The encryption key to be used for encrypting client sessions.
encryptKey :: a -> IO Word256
encryptKey _ = getKey defaultKeyFile
-- | All of the middlewares to install.
hackMiddleware :: a -> [Hack.Middleware]
hackMiddleware _ =
[ gzip
, cleanPath
, jsonp
, methodOverride
]
-- | Output error response pages.
errorHandler :: ErrorResult -> [ContentType] -> Handler a ContentPair
errorHandler = defaultErrorHandler
-- | Whether or not we should check for overlapping resource names.
checkOverlaps :: a -> Bool
checkOverlaps = const True
-- | An absolute URL to the root of the application.
approot :: a -> Approot
defaultErrorHandler :: Yesod y
=> ErrorResult
-> [ContentType]
-> Handler y ContentPair
defaultErrorHandler NotFound cts = do
rr <- askRawRequest
return $ chooseRep (toHtmlObject $ "Not found: " ++ show rr) cts
defaultErrorHandler (Redirect url) cts =
return $ chooseRep (toHtmlObject $ "Redirect to: " ++ url) cts
defaultErrorHandler PermissionDenied cts =
return $ chooseRep (toHtmlObject "Permission denied") cts
defaultErrorHandler (InvalidArgs ia) cts =
return $ chooseRep (toHtmlObject
[ ("errorMsg", toHtmlObject "Invalid arguments")
, ("messages", toHtmlObject ia)
]) cts
defaultErrorHandler (InternalError e) cts =
return $ chooseRep (toHtmlObject
[ ("Internal server error", e)
]) cts
toHackApp :: Yesod y => y -> Hack.Application
toHackApp a env = do
-- FIXME when (checkOverlaps a) $ checkResourceName a -- FIXME maybe this should be done compile-time?
key <- encryptKey a
let app' = toHackApp' a
clientsession' = clientsession [authCookieName] key -- FIXME gotta be a better way...
app = foldr ($) app' $ hackMiddleware a ++ [clientsession']
app env
toHackApp' :: Yesod y => y -> Hack.Application
toHackApp' = undefined -- FIXME