yesod/Yesod/Internal/Request.hs
2011-04-01 12:43:13 +03:00

60 lines
2.2 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
module Yesod.Internal.Request
( parseWaiRequest
) where
import Yesod.Request
import Control.Arrow (first, second)
import qualified Network.Wai.Parse as NWP
import Yesod.Internal
import qualified Network.Wai as W
import System.Random (randomR, newStdGen)
import Web.Cookie (parseCookiesText)
import Data.Monoid (mempty)
import qualified Data.ByteString.Char8 as S8
import Data.Text (Text, pack)
import Network.HTTP.Types (queryToQueryText)
import Control.Monad (join)
import Data.Maybe (fromMaybe)
parseWaiRequest :: W.Request
-> [(Text, Text)] -- ^ session
-> Maybe a
-> IO Request
parseWaiRequest env session' key' = do
let gets' = queryToQueryText $ W.queryString env
let reqCookie = maybe mempty id $ lookup "Cookie"
$ W.requestHeaders env
cookies' = parseCookiesText reqCookie
acceptLang = lookup "Accept-Language" $ W.requestHeaders env
langs = map (pack . S8.unpack) $ maybe [] NWP.parseHttpAccept acceptLang
langs' = case lookup langKey session' of
Nothing -> langs
Just x -> x : langs
langs'' = case lookup langKey cookies' of
Nothing -> langs'
Just x -> x : langs'
langs''' = case join $ lookup langKey gets' of
Nothing -> langs''
Just x -> x : langs''
nonce <- case (key', lookup nonceKey session') of
(Nothing, _) -> return Nothing
(_, Just x) -> return $ Just x
(_, Nothing) -> do
g <- newStdGen
return $ Just $ pack $ fst $ randomString 10 g
let gets'' = map (second $ fromMaybe "") gets'
return $ Request gets'' cookies' env langs''' nonce
where
randomString len =
first (map toChar) . sequence' (replicate len (randomR (0, 61)))
sequence' [] g = ([], g)
sequence' (f:fs) g =
let (f', g') = f g
(fs', g'') = sequence' fs g'
in (f' : fs', g'')
toChar i
| i < 26 = toEnum $ i + fromEnum 'A'
| i < 52 = toEnum $ i + fromEnum 'a' - 26
| otherwise = toEnum $ i + fromEnum '0' - 52