graphql/Data/GraphQL/Schema.hs

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module Data.GraphQL.Schema where
import Data.Maybe (catMaybes)
import Data.Text (Text)
import Data.Aeson (ToJSON(toJSON))
data Schema f = Schema (QueryRoot f) -- (Maybe MutationRoot)
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type QueryRoot f = Resolver f
type Resolver f = Input -> f (Output f)
data Output f = OutputResolver (Resolver f)
| OutputList (f [Output f])
| OutputScalar (f Scalar)
-- | OutputUnion [Output]
-- | OutputEnum [Scalar]
-- | OutputNonNull (Output)
data Input = InputScalar Scalar
| InputField Text
| InputList [Input]
deriving (Show)
field :: Input -> Maybe Text
field (InputField x) = Just x
field _ = Nothing
fields :: [Input] -> [Text]
fields = catMaybes . fmap field
data Scalar = ScalarInt Int
| ScalarFloat Double
| ScalarString Text
| ScalarBoolean Bool
| ScalarID Text
deriving (Show)
instance ToJSON Scalar where
toJSON (ScalarInt x) = toJSON x
toJSON (ScalarFloat x) = toJSON x
toJSON (ScalarString x) = toJSON x
toJSON (ScalarBoolean x) = toJSON x
toJSON (ScalarID x) = toJSON x