Use ToJSON instance for getting era in query tip command

cardano-api/src/Cardano/Api/Eras.hs

@@ -201,6 +201,9 @@ instance Bounded AnyCardanoEra where
     minBound = AnyCardanoEra ByronEra
     maxBound = AnyCardanoEra MaryEra
 
+instance ToJSON AnyCardanoEra where
+   toJSON (AnyCardanoEra era) = toJSON era
+
 -- | Like the 'AnyCardanoEra' constructor but does not demand a 'IsCardanoEra'
 -- class constraint.
 --

cardano-cli/src/Cardano/CLI/Shelley/Run/Query.hs

@@ -19,6 +19,7 @@ import           Prelude (String)
 
 import           Data.Aeson (ToJSON (..), (.=))
 import qualified Data.Aeson as Aeson
+import qualified Data.Aeson as J
 import           Data.Aeson.Encode.Pretty (encodePretty)
 import qualified Data.ByteString.Lazy.Char8 as LBS
 import qualified Data.HashMap.Strict as HMS
@@ -156,24 +157,13 @@ runQueryTip (AnyConsensusModeParams cModeParams) network mOutFile = do
   mEpoch <- mEpochQuery anyEra consensusMode  localNodeConnInfo
   tip <- liftIO $ getLocalChainTip localNodeConnInfo
   let output = encodePretty
-        . toObject "era" (Just (eraString anyEra))
+        . toObject "era" (Just (J.toJSON anyEra))
         . toObject "epoch" mEpoch
         $ toJSON tip
   case mOutFile of
     Just (OutputFile fpath) -> liftIO $ LBS.writeFile fpath output
     Nothing                 -> liftIO $ LBS.putStrLn        output
   where
-    eraString
-      :: AnyCardanoEra
-      -> String
-    eraString (AnyCardanoEra era) =
-      case cardanoEraStyle era of
-        LegacyByronEra -> "byron"
-        ShelleyBasedEra sbe -> case sbe of
-          ShelleyBasedEraShelley -> "shelley"
-          ShelleyBasedEraAllegra -> "allegra"
-          ShelleyBasedEraMary -> "mary"
-
     mEpochQuery
       :: AnyCardanoEra
       -> ConsensusMode mode