A.hs

{-# LANGUAGE ScopedTypeVariables #-}
module Split4.A 
    ( getPackages
    ) where

getPackages :: RepoKey -> Release -> PackageIndex -> IO (Either SomeException [BinaryPackage])
getPackages repo release index =
    fileFromURIStrict uri' >>= readControl . either (Left . SomeException) Right
    where
      readControl :: Either SomeException L.ByteString -> IO (Either SomeException [BinaryPackage])
      readControl (Left e) = return (Left e)
      readControl (Right s) =
          try (case controlFromIndex Uncompressed (show uri') s of
                 Left e -> return $ Left (SomeException (ErrorCall (show uri' ++ ": " ++ show e)))
                 Right (B.Control control) -> return (Right $ List.map (toBinaryPackage release index) control)) >>=
          return . either (\ (e :: SomeException) -> Left . SomeException . ErrorCall . ((show uri' ++ ":") ++) . show $ e) id
      uri' = uri {uriPath = uriPath uri </> packageIndexPath release index}
      uri = repoKeyURI repo