如何使用Happstack創建JSON Rest API？ JSON的身體？

Question

我想用Happstack創建一個JSON REST API。它應該允許帶有JSON主體的POSTS。我怎樣才能做到這一點？ happstack的API中的所有函數似乎都是基於參數名稱來查找的。它認爲身體始終是網址編碼的。

如果Happstack不可能，我應該使用哪個框架？

Answer 1

好吧，這就是我想到的。

{-# LANGUAGE OverloadedStrings, DeriveDataTypeable #-} 
import qualified Data.ByteString.Lazy.Char8 as L 
import Happstack.Server 
import Happstack.Server.Types 
import Control.Monad.IO.Class (liftIO) 

import Data.Data (Data, Typeable) 

-- easiest to serialize/deserialize objects 
data Unit = Unit { x :: Int, y :: Int } deriving (Show, Eq, Data, Typeable) 

-- put this function in a library somewhere 
getBody :: ServerPart L.ByteString 
getBody = do 
    req <- askRq 
    body <- liftIO $ takeRequestBody req 
    case body of 
     Just rqbody -> return . unBody $ rqbody 
     Nothing  -> return "" 

myRoute :: ServerPart Response 
myRoute = do 
    body <- getBody -- it's a ByteString 
    let unit = fromJust $ A.decode body :: Unit -- how to parse json 
    ok $ toResponse $ A.encode unit -- how to send json back.