209 lines
6.3 KiB
Haskell
209 lines
6.3 KiB
Haskell
{-# LANGUAGE QuasiQuotes #-}
|
|
-- | The basic typeclass for a Yesod application.
|
|
module Yesod.Yesod
|
|
( Yesod (..)
|
|
, YesodSite (..)
|
|
, simpleApplyLayout
|
|
, getApproot
|
|
, toWaiApp
|
|
, basicHandler
|
|
) where
|
|
|
|
import Yesod.Response
|
|
import Yesod.Request
|
|
import Yesod.Definitions
|
|
import Yesod.Hamlet
|
|
import Yesod.Handler hiding (badMethod)
|
|
import qualified Data.ByteString as B
|
|
import qualified Data.ByteString.Char8 as B8
|
|
import Data.Convertible.Text
|
|
import Text.Hamlet.Monad (fromList)
|
|
|
|
import Data.Maybe (fromMaybe)
|
|
import Web.Mime
|
|
import Web.Encodings (parseHttpAccept)
|
|
import Web.Routes (Site (..), encodePathInfo, decodePathInfo)
|
|
import Data.List (intercalate)
|
|
|
|
import qualified Network.Wai as W
|
|
import Network.Wai.Middleware.CleanPath
|
|
import Network.Wai.Middleware.ClientSession
|
|
import Network.Wai.Middleware.Jsonp
|
|
import Network.Wai.Middleware.MethodOverride
|
|
import Network.Wai.Middleware.Gzip
|
|
|
|
import qualified Network.Wai.Handler.SimpleServer as SS
|
|
import qualified Network.Wai.Handler.CGI as CGI
|
|
import System.Environment (getEnvironment)
|
|
|
|
class YesodSite y where
|
|
getSite :: Site (Routes y) (String -> YesodApp -> y -> YesodApp)
|
|
|
|
class YesodSite a => Yesod a where
|
|
-- | The encryption key to be used for encrypting client sessions.
|
|
encryptKey :: a -> IO Word256
|
|
encryptKey _ = getKey defaultKeyFile
|
|
|
|
-- | Number of minutes before a client session times out. Defaults to
|
|
-- 120 (2 hours).
|
|
clientSessionDuration :: a -> Int
|
|
clientSessionDuration = const 120
|
|
|
|
-- | Output error response pages.
|
|
errorHandler :: Yesod y => a -> ErrorResponse -> Handler y ChooseRep
|
|
errorHandler _ = defaultErrorHandler
|
|
|
|
-- | Applies some form of layout to <title> and <body> contents of a page. FIXME: use a Maybe here to allow subsites to simply inherit.
|
|
applyLayout :: a
|
|
-> PageContent (Routes a)
|
|
-> Request
|
|
-> Hamlet (Routes a) IO ()
|
|
applyLayout _ p _ = [$hamlet|
|
|
!!!
|
|
%html
|
|
%head
|
|
%title $pageTitle$
|
|
^pageHead^
|
|
%body
|
|
^pageBody^
|
|
|] p
|
|
|
|
-- | Gets called at the beginning of each request. Useful for logging.
|
|
onRequest :: a -> Request -> IO ()
|
|
onRequest _ _ = return ()
|
|
|
|
-- | An absolute URL to the root of the application. Do not include
|
|
-- trailing slash.
|
|
approot :: a -> Approot
|
|
|
|
-- | A convenience wrapper around 'simpleApplyLayout for HTML-only data.
|
|
simpleApplyLayout :: Yesod y
|
|
=> String -- ^ title
|
|
-> Hamlet (Routes y) IO () -- ^ body
|
|
-> Handler y ChooseRep
|
|
simpleApplyLayout t b = do
|
|
let pc = PageContent
|
|
{ pageTitle = return $ Unencoded $ cs t
|
|
, pageHead = return ()
|
|
, pageBody = b
|
|
}
|
|
y <- getYesod
|
|
rr <- getRequest
|
|
content <- hamletToContent $ applyLayout y pc rr
|
|
return $ chooseRep
|
|
[ (TypeHtml, content)
|
|
]
|
|
|
|
getApproot :: Yesod y => Handler y Approot
|
|
getApproot = approot `fmap` getYesod
|
|
|
|
defaultErrorHandler :: Yesod y => ErrorResponse -> Handler y ChooseRep
|
|
defaultErrorHandler NotFound = do
|
|
r <- waiRequest
|
|
simpleApplyLayout "Not Found" $ [$hamlet|
|
|
%h1 Not Found
|
|
%p $helper$
|
|
|] r
|
|
where
|
|
helper = return . Unencoded . cs . W.pathInfo
|
|
defaultErrorHandler PermissionDenied =
|
|
simpleApplyLayout "Permission Denied" $ [$hamlet|
|
|
%h1 Permission denied|] ()
|
|
defaultErrorHandler (InvalidArgs ia) =
|
|
simpleApplyLayout "Invalid Arguments" $ [$hamlet|
|
|
%h1 Invalid Arguments
|
|
%dl
|
|
$forall ias pair
|
|
%dt $pair.key$
|
|
%dd $pair.val$
|
|
|] ()
|
|
where
|
|
ias _ = return $ fromList $ map go ia
|
|
go (k, v) = Pair (return $ Unencoded $ cs k)
|
|
(return $ Unencoded $ cs v)
|
|
defaultErrorHandler (InternalError e) =
|
|
simpleApplyLayout "Internal Server Error" $ [$hamlet|
|
|
%h1 Internal Server Error
|
|
%p $message$
|
|
|] e
|
|
where
|
|
message :: String -> IO HtmlContent
|
|
message = return . Unencoded . cs
|
|
defaultErrorHandler (BadMethod m) =
|
|
simpleApplyLayout "Bad Method" $ [$hamlet|
|
|
%h1 Method Not Supported
|
|
%p Method "$m'$" not supported
|
|
|] ()
|
|
where
|
|
m' _ = return $ Unencoded $ cs m
|
|
|
|
data Pair m k v = Pair { key :: m k, val :: m v }
|
|
|
|
toWaiApp :: Yesod y => y -> IO W.Application
|
|
toWaiApp a = do
|
|
key' <- encryptKey a
|
|
let mins = clientSessionDuration a
|
|
return $ gzip
|
|
$ jsonp
|
|
$ methodOverride
|
|
$ cleanPath
|
|
$ \thePath -> clientsession encryptedCookies key' mins
|
|
$ toWaiApp' a thePath
|
|
|
|
toWaiApp' :: Yesod y
|
|
=> y
|
|
-> [B.ByteString]
|
|
-> [(B.ByteString, B.ByteString)]
|
|
-> W.Request
|
|
-> IO W.Response
|
|
toWaiApp' y resource session env = do
|
|
let site = getSite
|
|
method = B8.unpack $ W.methodToBS $ W.requestMethod env
|
|
types = httpAccept env
|
|
pathSegments = filter (not . null) $ cleanupSegments resource
|
|
eurl = parsePathSegments site pathSegments
|
|
render u = approot y ++ '/'
|
|
: encodePathInfo (fixSegs $ formatPathSegments site u)
|
|
rr <- parseWaiRequest env session
|
|
onRequest y rr
|
|
print pathSegments
|
|
let ya = case eurl of
|
|
Left _ -> runHandler (errorHandler y NotFound) y render
|
|
Right url -> handleSite site render url method
|
|
(badMethod method) y
|
|
let eh er = runHandler (errorHandler y er) y render
|
|
unYesodApp ya eh rr types >>= responseToWaiResponse
|
|
|
|
cleanupSegments :: [B.ByteString] -> [String]
|
|
cleanupSegments = decodePathInfo . intercalate "/" . map B8.unpack
|
|
|
|
httpAccept :: W.Request -> [ContentType]
|
|
httpAccept = map contentTypeFromBS
|
|
. parseHttpAccept
|
|
. fromMaybe B.empty
|
|
. lookup W.Accept
|
|
. W.requestHeaders
|
|
|
|
-- | Runs an application with CGI if CGI variables are present (namely
|
|
-- PATH_INFO); otherwise uses SimpleServer.
|
|
basicHandler :: Int -- ^ port number
|
|
-> W.Application -> IO ()
|
|
basicHandler port app = do
|
|
vars <- getEnvironment
|
|
case lookup "PATH_INFO" vars of
|
|
Nothing -> do
|
|
putStrLn $ "http://localhost:" ++ show port ++ "/"
|
|
SS.run port app
|
|
Just _ -> CGI.run app
|
|
|
|
badMethod :: String -> YesodApp
|
|
badMethod m = YesodApp $ \eh req cts
|
|
-> unYesodApp (eh $ BadMethod m) eh req cts
|
|
|
|
fixSegs :: [String] -> [String]
|
|
fixSegs [] = []
|
|
fixSegs [x]
|
|
| any (== '.') x = [x]
|
|
| otherwise = [x, ""] -- append trailing slash
|
|
fixSegs (x:xs) = x : fixSegs xs
|