servant/servant-docs/example/greet.hs
2015-04-20 11:19:48 +02:00

117 lines
3.9 KiB
Haskell

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TypeOperators #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
import Control.Lens
import Data.Aeson
import Data.Proxy
import Data.String.Conversions
import Data.Text (Text)
import GHC.Generics
import Servant.API
import Servant.Docs
-- * Example
-- | A greet message data type
newtype Greet = Greet Text
deriving (Generic, Show)
-- | We can get JSON support automatically. This will be used to parse
-- and encode a Greeting as 'JSON'.
instance FromJSON Greet
instance ToJSON Greet
-- | We can also implement 'MimeRender' for additional formats like 'PlainText'.
instance MimeRender PlainText Greet where
mimeRender Proxy (Greet s) = "\"" <> cs s <> "\""
-- We add some useful annotations to our captures,
-- query parameters and request body to make the docs
-- really helpful.
instance ToCapture (Capture "name" Text) where
toCapture _ = DocCapture "name" "name of the person to greet"
instance ToCapture (Capture "greetid" Text) where
toCapture _ = DocCapture "greetid" "identifier of the greet msg to remove"
instance ToParam (QueryParam "capital" Bool) where
toParam _ =
DocQueryParam "capital"
["true", "false"]
"Get the greeting message in uppercase (true) or not (false).\
\Default is false."
Normal
instance ToParam (MatrixParam "lang" String) where
toParam _ =
DocQueryParam "lang"
["en", "sv", "fr"]
"Get the greeting message selected language. Default is en."
Normal
instance ToSample Greet where
toSample = Just $ Greet "Hello, haskeller!"
toSamples =
[ ("If you use ?capital=true", Greet "HELLO, HASKELLER")
, ("If you use ?capital=false", Greet "Hello, haskeller")
]
-- We define some introductory sections, these will appear at the top of the
-- documentation.
--
-- We pass them in with 'docsWith', below. If you only want to add
-- introductions, you may use 'docsWithIntros'
intro1 :: DocIntro
intro1 = DocIntro "On proper introductions." -- The title
[ "Hello there."
, "As documentation is usually written for humans, it's often useful \
\to introduce concepts with a few words." ] -- Elements are paragraphs
intro2 :: DocIntro
intro2 = DocIntro "This title is below the last"
[ "You'll also note that multiple intros are possible." ]
-- API specification
type TestApi =
-- GET /hello/:name?capital={true, false} returns a Greet as JSON or PlainText
"hello" :> MatrixParam "lang" String :> Capture "name" Text :> QueryParam "capital" Bool :> Get '[JSON, PlainText] Greet
-- POST /greet with a Greet as JSON in the request body,
-- returns a Greet as JSON
:<|> "greet" :> ReqBody '[JSON] Greet :> Post '[JSON] Greet
-- DELETE /greet/:greetid
:<|> "greet" :> Capture "greetid" Text :> Delete
testApi :: Proxy TestApi
testApi = Proxy
-- Build some extra information for the DELETE /greet/:greetid endpoint. We
-- want to add documentation about a secret unicorn header and some extra
-- notes.
extra :: ExtraInfo TestApi
extra =
extraInfo (Proxy :: Proxy ("greet" :> Capture "greetid" Text :> Delete)) $
defAction & headers <>~ ["unicorns"]
& notes <>~ [ DocNote "Title" ["This is some text"]
, DocNote "Second secton" ["And some more"]
]
-- Generate the data that lets us have API docs. This
-- is derived from the type as well as from
-- the 'ToCapture', 'ToParam' and 'ToSample' instances from above.
--
-- If you didn't want intros and extra information, you could just call:
--
-- > docs testAPI :: API
docsGreet :: API
docsGreet = docsWith [intro1, intro2] extra testApi
main :: IO ()
main = putStrLn $ markdown docsGreet