{-# LANGUAGE OverloadedStrings #-}

import qualified Aws
import qualified Aws.S3 as S3
import Data.Conduit
import Data.Conduit.Binary
import Data.IORef
import Data.Monoid

{- A small function to save the object's data into a file. -}
saveObject :: Aws.HTTPResponseConsumer ()
saveObject status headers source = source $$+- sinkFile "cloud-remote.pdf"

main :: IO ()
main = do
  {- Set up AWS credentials and the default configuration. -}
  cfg <- Aws.baseConfiguration
  let s3Cfg = Aws.defServiceConfig

  {- Create an IORef to store the response Metadata (so it is also available in case of an error). -}
  metadataRef <- newIORef mempty

  {- Create a request object with S3.getObject and run the request with simpleAwsRef. -}
  Aws.simpleAwsRef cfg s3Cfg metadataRef $ S3.getObject "haskell-aws" "cloud-remote.pdf" saveObject

  {- Print the response metadata. -}
  print =<< readIORef metadataRef