aws-sdk-0.2.0.0: AWS/Util.hs

module AWS.Util where

import Data.ByteString (ByteString)
import qualified Data.ByteString as BS
import qualified Data.ByteString.Char8 as BSC
import qualified Data.ByteString.Lazy as BSL
import Data.Text (Text)
import qualified Data.Text as T
import qualified Data.Text.Read as TR
import Data.Time (UTCTime)
import qualified Data.Time as Time
import qualified Data.Time.Parse as TP

toS :: BSL.ByteString -> ByteString
toS = BS.concat . BSL.toChunks

toL :: ByteString -> BSL.ByteString
toL = BSL.fromChunks . (:[])

bsShow :: Show a => a -> ByteString
bsShow = BSC.pack . show

err :: String -> Text -> a
err v m = error $ "unknown " ++ v ++ ": " ++ T.unpack m

textToBool :: Text -> Bool
textToBool a
    | a == "true"  = True
    | a == "false" = False
    | otherwise    = err "value" a

textToInt :: Integral a => Text -> a
textToInt t = either 
    (const $ error "not decimal")
    fst
    (TR.signed TR.decimal t)

textToTime :: Text -> UTCTime
textToTime
    = Time.localTimeToUTC Time.utc
    . maybe (error "time format error.") fst
    . TP.strptime fmt
    . T.unpack
  where
    fmt = "%FT%T"

orEmpty :: Maybe Text -> Text
orEmpty = maybe "" id

boolToText :: Bool -> Text
boolToText True  = "true"
boolToText False = "false"

toText :: Show a => a -> Text
toText = T.pack . show

bsToText :: ByteString -> Text
bsToText = T.pack . BSC.unpack

textToBS :: Text -> ByteString
textToBS = BSC.pack . T.unpack