45 lines
1,002 B
Haskell
45 lines
1,002 B
Haskell
{-# LANGUAGE DataKinds #-}
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{-# LANGUAGE TypeFamilies #-}
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{-# LANGUAGE DeriveGeneric #-}
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{-# LANGUAGE TypeOperators #-}
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import Data.Aeson
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import Data.Time.Calendar
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import GHC.Generics
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import Network.Wai.Handler.Warp (run)
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import Servant
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data User = User
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{ name :: String
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, age :: Int
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, email :: String
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, registration_date :: Day
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} deriving (Eq, Show, Generic)
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-- orphan ToJSON instance for Day. necessary to derive one for User
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instance ToJSON Day where
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-- display a day in YYYY-mm-dd format
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toJSON d = toJSON (showGregorian d)
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instance ToJSON User
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type UserAPI = "users" :> Get '[JSON] [User]
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users :: [User]
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users =
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[ User "Isaac Newton" 372 "isaac@newton.co.uk" (fromGregorian 1683 3 1)
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, User "Albert Einstein" 136 "ae@mc2.org" (fromGregorian 1905 12 1)
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]
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userAPI :: Proxy UserAPI
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userAPI = Proxy
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server :: Server UserAPI
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server = return users
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runServer :: Int -> IO ()
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runServer port = run port (serve userAPI server)
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main :: IO ()
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main = runServer 8081
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