gql2hs/app/Main.hs

{-# OPTIONS_GHC -Wall #-}
module Main where

import Control.Category ((>>>))
import Control.Monad ((>=>))
import Control.Monad.Fail (fail)
import Data.Attoparsec.Text (Parser)
import Data.Foldable (traverse_)
import Data.Text (Text)
import Language.Haskell.Exts.Pretty
import Prelude hiding (fail)
import qualified Data.Attoparsec.Text as Parser
import qualified Data.Text.IO as Text
import qualified GraphQL.Internal.Syntax.AST as GraphQL
import qualified GraphQL.Internal.Syntax.Parser as GraphQL.Parser
import qualified Language.GraphQL.Reflection as GraphQL
import qualified System.Environment as System

main :: IO ()
main = System.getArgs >>= traverse_ run

run :: FilePath -> IO ()
run = parseFile >=> (GraphQL.schemaDocument >>> traverse_ (prettyPrint >>> putStrLn))

parseFile :: FilePath -> IO GraphQL.SchemaDocument
parseFile p = do
  txt <- Text.readFile p
  parse GraphQL.Parser.schemaDocument txt

parse :: Parser a -> Text -> IO a
parse p = Parser.parseOnly p >>> either fail pure