[graphql] NUTCTime for gql serialization

src/Gargantext/Utils/UTCTime.hs

+{-# LANGUAGE DeriveAnyClass             #-}
+{-# LANGUAGE DeriveGeneric              #-}
+{-# LANGUAGE TypeFamilies               #-}
+
+module Gargantext.Utils.UTCTime where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Either (Either(..))
+import Data.Morpheus.Kind (SCALAR)
+import Data.Morpheus.Types (GQLType(..), DecodeScalar(..), EncodeScalar(..))
+import qualified Data.Morpheus.Types as DMT
+import Data.Swagger (ToSchema)
+import qualified Data.Text as T
+import Data.Time (UTCTime)
+import Gargantext.Prelude
+import GHC.Generics (Generic)
+import Text.Read (readEither)
+
+
+newtype NUTCTime = NUTCTime UTCTime
+  deriving (Eq, Show, Generic)
+instance DecodeScalar NUTCTime where
+  decodeScalar (DMT.String x) = case (readEither $ T.unpack x) of
+    Right r  -> pure $ NUTCTime r
+    Left err -> Left $ T.pack err
+  decodeScalar          _ = Left "Invalid value for NUTCTime"
+instance EncodeScalar NUTCTime where
+  encodeScalar (NUTCTime x) = DMT.String $ T.pack $ show x
+instance GQLType NUTCTime where
+  type KIND NUTCTime = SCALAR
+instance FromJSON NUTCTime
+instance ToJSON NUTCTime
+instance ToSchema NUTCTime