core: fix VersionRange JSON instances (#1037)

src/Simplex/Messaging/Version.hs

@@ -2,9 +2,9 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE FunctionalDependencies #-}
+{-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE PatternSynonyms #-}
-{-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE TypeFamilies #-}
 
 module Simplex.Messaging.Version
@@ -27,11 +27,13 @@ module Simplex.Messaging.Version
 where
 
 import Control.Applicative (optional)
-import qualified Data.Aeson.TH as J
+import qualified Data.Aeson as J
+import qualified Data.Aeson.Encoding as JE
+import Data.Aeson.Types ((.:), (.=))
+import qualified Data.Aeson.Types as JT
 import qualified Data.Attoparsec.ByteString.Char8 as A
 import Simplex.Messaging.Encoding
 import Simplex.Messaging.Encoding.String
-import Simplex.Messaging.Parsers (defaultJSON)
 import Simplex.Messaging.Version.Internal (Version (..))
 
 pattern VersionRange :: Version v -> Version v -> VersionRange v
@@ -45,6 +47,18 @@ data VersionRange v = VRange
   }
   deriving (Eq, Show)
 
+instance J.FromJSON (VersionRange v) where
+  parseJSON (J.Object v) = do
+    minVersion <- v .: "minVersion"
+    maxVersion <- v .: "maxVersion"
+    pure VRange {minVersion, maxVersion}
+  parseJSON invalid =
+    JT.prependFailure "bad VersionRange, " (JT.typeMismatch "Object" invalid)
+
+instance J.ToJSON (VersionRange v) where
+  toEncoding VRange {minVersion, maxVersion} = JE.pairs $ ("minVersion" .= minVersion) <> ("maxVersion" .= maxVersion)
+  toJSON VRange {minVersion, maxVersion} = J.object ["minVersion" .= minVersion, "maxVersion" .= maxVersion]
+
 class VersionScope v
 
 -- | construct valid version range, to be used in constants
@@ -123,5 +137,3 @@ compatibleVersion x vr =
 
 mkCompatibleIf :: a -> Bool -> Maybe (Compatible a)
 x `mkCompatibleIf` cond = if cond then Just $ Compatible_ x else Nothing
-
-$(J.deriveJSON defaultJSON ''VersionRange)