choirMail/app/Config.hs

{-# LANGUAGE OverloadedStrings #-}
module Config where
  
import qualified Toml
import Toml(TomlCodec, (.=))
import qualified Data.Text as T
import Monad

data Config = Config {
  mailDomain :: String
  ,mailUsername :: String
  ,mailPassword :: String
  ,mailTo       :: T.Text
  ,mailFrom     :: T.Text
  ,mailErrorTo  :: T.Text
  } deriving Show

configCodec :: TomlCodec Config
configCodec = flip Toml.table "mail" $ Config
  <$> Toml.string "domain"   .= mailDomain
  <*> Toml.string "user"     .= mailUsername
  <*> Toml.string "password" .= mailPassword
  <*> Toml.text   "to"       .= mailTo
  <*> Toml.text   "from"     .= mailFrom
  <*> Toml.text   "errorTo"  .= mailErrorTo

parseConfigFile :: (MonadIO m, MonadFail m) => String -> m Config
parseConfigFile path = do
  config <- liftIO $ Toml.decodeFileEither configCodec path
  case config of
    Left errors -> fail $ unwords $ fmap show errors
    Right x -> return x