Get Scientific instances

CHANGELOG.md

@@ -8,8 +8,8 @@ and this project adheres to
 
 ## [Unreleased]
 ### Added
-- `ToGraphQL` and `FromGraphQL` instances for `Word` types, `Float` and
-  `Double`.
+- `ToGraphQL` and `FromGraphQL` instances for `Word` types, `Float`, `Double`,
+  and `Scientific`.
 - `Resolver`: Export `ServerException`.
 - `Resolver.defaultResolver`: Throw `FieldNotResolvedException` if the requested
   field is not in the parent object.

src/Language/GraphQL/Class.hs

@@ -19,6 +19,7 @@ import qualified Data.Text.Read as Text.Read
 import Data.Vector (Vector)
 import qualified Data.Vector as Vector
 import qualified Language.GraphQL.Type as Type
+import Data.Scientific (Scientific, toRealFloat)
 
 fromGraphQLToIntegral :: Integral a => Type.Value -> Maybe a
 fromGraphQLToIntegral (Type.Int value) = Just $ fromIntegral value
@@ -30,121 +31,166 @@ fromGraphQLToIntegral _ = Nothing
 
 -- | Instances of this typeclass can be converted to GraphQL internal
 -- representation.
-class ToGraphQL a where
+class ToGraphQL a
+  where
     toGraphQL :: a -> Type.Value
 
-instance ToGraphQL Text where
+instance ToGraphQL Text
+  where
     toGraphQL = Type.String
 
-instance ToGraphQL Int where
+instance ToGraphQL Int
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Int8 where
+instance ToGraphQL Int8
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Int16 where
+instance ToGraphQL Int16
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Int32 where
+instance ToGraphQL Int32
+  where
     toGraphQL = Type.Int
 
-instance ToGraphQL Int64 where
+instance ToGraphQL Int64
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Word where
+instance ToGraphQL Word
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Word8 where
+instance ToGraphQL Word8
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Word16 where
+instance ToGraphQL Word16
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Word32 where
+instance ToGraphQL Word32
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL Word64 where
+instance ToGraphQL Word64
+  where
     toGraphQL = Type.Int . fromIntegral
 
-instance ToGraphQL a => ToGraphQL [a] where
+instance ToGraphQL a => ToGraphQL [a]
+  where
     toGraphQL = Type.List . fmap toGraphQL
 
-instance ToGraphQL a => ToGraphQL (Vector a) where
+instance ToGraphQL a => ToGraphQL (Vector a)
+  where
     toGraphQL = Type.List . toList . fmap toGraphQL
 
-instance ToGraphQL a => ToGraphQL (Maybe a) where
+instance ToGraphQL a => ToGraphQL (Maybe a)
+  where
     toGraphQL (Just justValue) = toGraphQL justValue
     toGraphQL Nothing = Type.Null
 
-instance ToGraphQL Bool where
+instance ToGraphQL Bool
+  where
     toGraphQL = Type.Boolean
 
-instance ToGraphQL Float where
+instance ToGraphQL Float
+  where
     toGraphQL = Type.Float . realToFrac
 
-instance ToGraphQL Double where
+instance ToGraphQL Double
+  where
     toGraphQL = Type.Float
 
+instance ToGraphQL Scientific
+  where
+    toGraphQL = Type.Float . toRealFloat
+
 -- | Instances of this typeclass can be used to convert GraphQL internal
 -- representation to user-defined type.
-class FromGraphQL a where
+class FromGraphQL a
+  where
     fromGraphQL :: Type.Value -> Maybe a
 
-instance FromGraphQL Text where
+instance FromGraphQL Text
+  where
     fromGraphQL (Type.String value) = Just value
     fromGraphQL _ = Nothing
 
-instance FromGraphQL Int where
+instance FromGraphQL Int
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Int8 where
+instance FromGraphQL Int8
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Int16 where
+instance FromGraphQL Int16
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Int32 where
+instance FromGraphQL Int32
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Int64 where
+instance FromGraphQL Int64
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Word where
+instance FromGraphQL Word
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Word8 where
+instance FromGraphQL Word8
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Word16 where
+instance FromGraphQL Word16
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Word32 where
+instance FromGraphQL Word32
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL Word64 where
+instance FromGraphQL Word64
+  where
     fromGraphQL = fromGraphQLToIntegral
 
-instance FromGraphQL a => FromGraphQL [a] where
+instance FromGraphQL a => FromGraphQL [a]
+  where
     fromGraphQL (Type.List value) = traverse fromGraphQL value
     fromGraphQL _ = Nothing
 
-instance FromGraphQL a => FromGraphQL (Vector a) where
+instance FromGraphQL a => FromGraphQL (Vector a)
+  where
     fromGraphQL (Type.List value) = Vector.fromList
         <$> traverse fromGraphQL value
     fromGraphQL _ = Nothing
 
-instance FromGraphQL a => FromGraphQL (Maybe a) where
+instance FromGraphQL a => FromGraphQL (Maybe a)
+  where
     fromGraphQL Type.Null = Just Nothing
     fromGraphQL value = Just <$> fromGraphQL value
 
-instance FromGraphQL Bool where
+instance FromGraphQL Bool
+  where
     fromGraphQL (Type.Boolean value) = Just value
     fromGraphQL _ = Nothing
 
-instance FromGraphQL Float where
+instance FromGraphQL Float
+  where
     fromGraphQL (Type.Float value) = Just $ realToFrac value
     fromGraphQL _ = Nothing
 
-instance FromGraphQL Double where
+instance FromGraphQL Double
+  where
     fromGraphQL (Type.Float value) = Just value
     fromGraphQL _ = Nothing
+
+instance FromGraphQL Scientific
+  where
+    fromGraphQL (Type.Float value) = Just $ realToFrac value
+    fromGraphQL _ = Nothing