52 lines
1.2 KiB
Haskell
52 lines
1.2 KiB
Haskell
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{-# LANGUAGE DataKinds #-}
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{-# LANGUAGE DeriveGeneric #-}
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{-# LANGUAGE OverloadedStrings #-}
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import Data.Aeson
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import Data.Text
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import GHC.Generics
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import Network.Wai
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import Network.Wai.Handler.Warp
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import Network.Wai.Middleware.RequestLogger
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import Servant
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data Product = Product
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{ name :: Text
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, brand :: Text
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, current_price_eur :: Double
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, available :: Bool
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} deriving (Eq, Show, Generic)
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instance ToJSON Product
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products :: [Product]
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products = [p1, p2]
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where p1 = Product "Haskell laptop sticker"
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"GHC Industries"
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2.50
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True
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p2 = Product "Foldable USB drive"
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"Well-Typed"
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13.99
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False
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type SimpleAPI = Get '[JSON] [Product]
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simpleAPI :: Proxy SimpleAPI
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simpleAPI = Proxy
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server :: Server SimpleAPI
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server = return products
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-- logStdout :: Middleware
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-- i.e, logStdout :: Application -> Application
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-- serve :: Proxy api -> Server api -> Application
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-- so applying a middleware is really as simple as
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-- applying a function to the result of 'serve'
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app :: Application
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app = logStdout (serve simpleAPI server)
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main :: IO ()
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main = run 8080 app
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