ModKeys

ModKeys.hs

module ModKeys where

import Data.Aeson
import Data.Text (Text)
import GHC.Generics (Generic)

import qualified Data.Aeson as Aeson
import qualified Data.ByteString.Lazy as LBS
import qualified Data.Text.Encoding as E
import qualified Data.Text.IO as TIO

data Foo = Foo
  { name :: Text
  , x :: X
  }
  deriving (Generic, Show)

aesonOptions :: Aeson.Options
aesonOptions =
  defaultOptions
    { fieldLabelModifier = \x -> "field_" <> x
    , constructorTagModifier = \x -> "cons_" <> x
    , sumEncoding = ObjectWithSingleField
    , unwrapUnaryRecords = True
    }

instance ToJSON Foo where
  toJSON = genericToJSON aesonOptions
  toEncoding = genericToEncoding aesonOptions

data X = A String | B Int
  deriving (Eq, Show, Generic)

instance ToJSON X where
  toJSON = genericToJSON aesonOptions
  toEncoding = genericToEncoding aesonOptions

instance FromJSON X where
  parseJSON = genericParseJSON aesonOptions

keyFunc :: IO ()
keyFunc = do
  let something =
        Foo
          { name = "Dummy"
          , x = A "Foo"
          }

  -- I would want this to be: {"field_name": "Dummy", "cons_A": "Foo"},
  -- instead of: {"field_name":"Dummy","field_x":{"cons_A":"Foo"}}
  TIO.putStrLn . E.decodeUtf8 . LBS.toStrict . encode $ something