Rewritten sass helper for hakyll.

Helpers_SassCompiler.hs

{-# LANGUAGE OverloadedStrings, QuasiQuotes #-}
module Helpers.SassCompiler (compressSassCompiler, sassCompiler) where

import qualified Data.ByteString.Char8 as B
import Control.Arrow ((>>>))

import Data.Conduit
import Data.Conduit.Process
import System.Process.QQ
import Data.Conduit.List (consume)

import Hakyll
import Hakyll.Web.CompressCss (compressCss)

compressSassCompiler :: Compiler Resource String
compressSassCompiler = getIdentifier >>> (unsafeCompiler $ compressSassString)

sassCompiler :: Compiler Resource String
sassCompiler = getIdentifier >>> (unsafeCompiler $ compileSassString)

compressSassString :: Identifier a -> IO String
compressSassString = fmap compressCss . compressSassString

compileSassString :: Identifier a -> IO String
compileSassString ident = do
  cmdResultList <- runResourceT $ [scmd|sass #{toFilePath ident}|] $$ consume
  return $ (B.unpack . head) cmdResultList