yesod/yesod-core/Yesod/Request.hs
2012-07-02 11:20:17 +03:00

109 lines
3.0 KiB
Haskell

---------------------------------------------------------
--
-- Module : Yesod.Request
-- Copyright : Michael Snoyman
-- License : BSD3
--
-- Maintainer : Michael Snoyman <michael@snoyman.com>
-- Stability : Stable
-- Portability : portable
--
-- | Provides a parsed version of the raw 'W.Request' data.
--
---------------------------------------------------------
module Yesod.Request
(
-- * Request datatype
RequestBodyContents
, Request (..)
, FileInfo
, fileName
, fileContentType
, fileSource
, fileMove
-- * Convenience functions
, languages
-- * Lookup parameters
, lookupGetParam
, lookupPostParam
, lookupCookie
, lookupFile
-- ** Multi-lookup
, lookupGetParams
, lookupPostParams
, lookupCookies
, lookupFiles
) where
import Yesod.Internal.Request
import Yesod.Handler
import Control.Monad (liftM)
import Control.Monad.Instances () -- I'm missing the instance Monad ((->) r
import Data.Maybe (listToMaybe)
import Data.Text (Text)
-- | Get the list of supported languages supplied by the user.
--
-- Languages are determined based on the following three (in descending order
-- of preference):
--
-- * The _LANG get parameter.
--
-- * The _LANG cookie.
--
-- * The _LANG user session variable.
--
-- * Accept-Language HTTP header.
--
-- Yesod will seek the first language from the returned list matched with languages supporting by your application. This language will be used to render i18n templates.
-- If a matching language is not found the default language will be used.
--
-- This is handled by parseWaiRequest (not exposed).
languages :: GHandler s m [Text]
languages = reqLangs `liftM` getRequest
lookup' :: Eq a => a -> [(a, b)] -> [b]
lookup' a = map snd . filter (\x -> a == fst x)
-- | Lookup for GET parameters.
lookupGetParams :: Text -> GHandler s m [Text]
lookupGetParams pn = do
rr <- getRequest
return $ lookup' pn $ reqGetParams rr
-- | Lookup for GET parameters.
lookupGetParam :: Text -> GHandler s m (Maybe Text)
lookupGetParam = liftM listToMaybe . lookupGetParams
-- | Lookup for POST parameters.
lookupPostParams :: Text -> GHandler s m [Text]
lookupPostParams pn = do
(pp, _) <- runRequestBody
return $ lookup' pn pp
lookupPostParam :: Text
-> GHandler s m (Maybe Text)
lookupPostParam = liftM listToMaybe . lookupPostParams
-- | Lookup for POSTed files.
lookupFile :: Text
-> GHandler s m (Maybe FileInfo)
lookupFile = liftM listToMaybe . lookupFiles
-- | Lookup for POSTed files.
lookupFiles :: Text
-> GHandler s m [FileInfo]
lookupFiles pn = do
(_, files) <- runRequestBody
return $ lookup' pn files
-- | Lookup for cookie data.
lookupCookie :: Text -> GHandler s m (Maybe Text)
lookupCookie = liftM listToMaybe . lookupCookies
-- | Lookup for cookie data.
lookupCookies :: Text -> GHandler s m [Text]
lookupCookies pn = do
rr <- getRequest
return $ lookup' pn $ reqCookies rr