如何在servant应用程序中访问原始请求体

import Network.Wai (requestBody, RequestBodyLength(..))
import Network.Wai.Parse (sinkRequestBody)
import Servant (Handler, ServerError, err400)
import Servant.Server.Internal.Handler (withRequest)

data RawRequestBody = RawRequestBody ByteString

getRawRequestBody :: Handler RawRequestBody
getRawRequestBody = withRequest $ \request -> do
  body <- liftIO $ requestBody request
  case body of
    (RequestBodyLBS lbs) -> return $ RawRequestBody $ toStrict lbs
    _ -> throwError $ err400 { errBody = "Invalid request body" }

type MyAPI = "endpoint" :> ReqBody '[OctetStream] RawRequestBody :> Get '[JSON] MyResponse

myServer :: Server MyAPI
myServer = getRawRequestBody :<|> otherEndpoints