Warp: with static subdomain

warp.hs

{-# LANGUAGE OverloadedStrings #-}

import Control.Monad.Trans.Resource (ResourceT)
import Filesystem.Path.CurrentOS (decodeString)
import Network.HTTP.Types (status200)
import Network.Wai (responseLBS, rawPathInfo, Request, Response)
import Network.Wai.Handler.Warp (run)
import Network.Wai.Application.Static (staticApp, defaultFileServerSettings)
import Network.Wai.Middleware.Vhost (vhost)
import qualified Data.ByteString as S

sayHello :: Request -> ResourceT IO Response
sayHello _ = do
    return $ responseLBS status200 [("Content-Type", "text/plain")] "hello"

main :: IO ()
main = do
    let settings = defaultFileServerSettings $ decodeString "/srv/http/"
    putStrLn $ "http://localhost:3000/"
    run 3000 $ vhost 
        [((S.isPrefixOf "/static/") . rawPathInfo, staticApp settings)
        ] sayHello