JSONString.hs

{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE OverloadedStrings #-}

module Eventium.Store.Sql.JSONString
  ( JSONString,
    jsonStringSerializer,
  )
where

import Data.Aeson
import Data.Text.Lazy (Text)
import qualified Data.Text.Lazy.Encoding as TLE
import Database.Persist
import Database.Persist.Sql
import Eventium.Serializer

-- | A more specific type than just ByteString for JSON data.
newtype JSONString = JSONString {unJSONString :: Text}
  deriving (Eq, PersistField)

instance PersistFieldSql JSONString where
  sqlType _ = SqlOther "jsonb"

instance Show JSONString where
  show = show . unJSONString

jsonStringSerializer :: (ToJSON a, FromJSON a) => Serializer a JSONString
jsonStringSerializer =
  Serializer
    encodeJSON
    decodeJSON
    decodeJSONEither

encodeJSON :: (ToJSON a) => a -> JSONString
encodeJSON = JSONString . TLE.decodeUtf8 . encode

decodeJSON :: (FromJSON a) => JSONString -> Maybe a
decodeJSON = decode . TLE.encodeUtf8 . unJSONString

decodeJSONEither :: (FromJSON a) => JSONString -> Either String a
decodeJSONEither = eitherDecode . TLE.encodeUtf8 . unJSONString