{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
module Language.GraphQL.Error
( parseError
, CollectErrsT
, Error(..)
, Resolution(..)
, ResolverException(..)
, Response(..)
, ResponseEventStream
, addErr
, addErrMsg
, runCollectErrs
, singleError
) where
import Conduit
import Control.Exception (Exception(..))
import Control.Monad.Trans.State (StateT, modify, runStateT)
import Data.HashMap.Strict (HashMap)
import Data.Sequence (Seq(..), (|>))
import qualified Data.Sequence as Seq
import Data.Text (Text)
import qualified Data.Text as Text
import Language.GraphQL.AST (Location(..), Name)
import Language.GraphQL.Execute.Coerce
import Language.GraphQL.Type.Schema
import Prelude hiding (null)
import Text.Megaparsec
( ParseErrorBundle(..)
, PosState(..)
, SourcePos(..)
, errorOffset
, parseErrorTextPretty
, reachOffset
, unPos
)
data Resolution m = Resolution
{ errors :: Seq Error
, types :: HashMap Name (Type m)
}
parseError :: (Applicative f, Serialize a)
=> ParseErrorBundle Text Void
-> f (Response a)
parseError ParseErrorBundle{..} =
pure $ Response null $ fst
$ foldl go (Seq.empty, bundlePosState) bundleErrors
where
errorObject s SourcePos{..} = Error
{ message = Text.pack $ init $ parseErrorTextPretty s
, locations = [Location (unPos' sourceLine) (unPos' sourceColumn)]
}
unPos' = fromIntegral . unPos
go (result, state) x =
let (_, newState) = reachOffset (errorOffset x) state
sourcePosition = pstateSourcePos newState
in (result |> errorObject x sourcePosition, newState)
type CollectErrsT m = StateT (Resolution m) m
addErr :: Monad m => Error -> CollectErrsT m ()
addErr v = modify appender
where
appender :: Monad m => Resolution m -> Resolution m
appender resolution@Resolution{..} = resolution{ errors = errors |> v }
makeErrorMessage :: Text -> Error
makeErrorMessage s = Error s []
singleError :: Serialize a => Text -> Response a
singleError message = Response null $ Seq.singleton $ makeErrorMessage message
addErrMsg :: (Monad m, Serialize a) => Text -> CollectErrsT m a
addErrMsg errorMessage = (addErr . makeErrorMessage) errorMessage >> pure null
data Error = Error
{ message :: Text
, locations :: [Location]
} deriving (Eq, Show)
data Response a = Response
{ data' :: a
, errors :: Seq Error
} deriving (Eq, Show)
type ResponseEventStream m a = ConduitT () (Response a) m ()
data ResolverException = forall e. Exception e => ResolverException e
instance Show ResolverException where
show (ResolverException e) = show e
instance Exception ResolverException
runCollectErrs :: (Monad m, Serialize a)
=> HashMap Name (Type m)
-> CollectErrsT m a
-> m (Response a)
runCollectErrs types' res = do
(dat, Resolution{..}) <- runStateT res
$ Resolution{ errors = Seq.empty, types = types' }
pure $ Response dat errors