refactor a bit + add GS2

servant-examples/getting-started/GS1.hs

@@ -2,11 +2,12 @@
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE TypeOperators #-}
+module GS1 where
 
 import Data.Aeson
 import Data.Time.Calendar
 import GHC.Generics
-import Network.Wai.Handler.Warp (run)
+import Network.Wai
 import Servant
 
 data User = User
@@ -37,9 +38,5 @@ userAPI = Proxy
 server :: Server UserAPI
 server = return users
 
-runServer :: Int -> IO ()
+app :: Application
-runServer port = run port (serve userAPI server)
+app = serve userAPI server
-
-main :: IO ()
-main = runServer 8081
-

servant-examples/getting-started/GS2.hs

@@ -0,0 +1,49 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE TypeOperators #-}
+module GS2 where
+
+import Data.Aeson
+import Data.Time.Calendar
+import GHC.Generics
+import Network.Wai
+import Servant
+
+data User = User
+  { name :: String
+  , age :: Int
+  , email :: String
+  , registration_date :: Day
+  } deriving (Eq, Show, Generic)
+
+-- orphan ToJSON instance for Day. necessary to derive one for User
+instance ToJSON Day where
+  -- display a day in YYYY-mm-dd format
+  toJSON d = toJSON (showGregorian d)
+
+instance ToJSON User
+
+type UserAPI = "users" :> Get '[JSON] [User]
+          :<|> "albert" :> Get '[JSON] User
+          :<|> "isaac" :> Get '[JSON] User
+
+isaac :: User
+isaac = User "Isaac Newton" 372 "isaac@newton.co.uk" (fromGregorian 1683 3 1)
+
+albert :: User
+albert = User "Albert Einstein" 136 "ae@mc2.org" (fromGregorian 1905 12 1)
+
+users :: [User]
+users = [isaac, albert]
+
+userAPI :: Proxy UserAPI
+userAPI = Proxy
+
+server :: Server UserAPI
+server = return users
+    :<|> return albert
+    :<|> return isaac
+
+app :: Application
+app = serve userAPI server

servant-examples/getting-started/getting-started.hs

@@ -0,0 +1,24 @@
+import Network.Wai
+import Network.Wai.Handler.Warp
+import System.Environment
+
+import qualified GS1
+import qualified GS2
+
+app :: String -> Maybe Application
+app n = case n of
+  "1" -> Just GS1.app
+  "2" -> Just GS2.app
+  _   -> Nothing
+
+main :: IO ()
+main = do
+  args <- getArgs
+  case args of
+    [n] -> maybe usage (run 8081) (app n)
+    _   -> usage
+
+usage :: IO ()
+usage = do
+  putStrLn "Usage:\t getting-started N"
+  putStrLn "\t\twhere N is the number of the example you want to run."

servant-examples/servant-examples.cabal

@@ -13,8 +13,9 @@ category:            Web
 build-type:          Simple
 cabal-version:       >=1.10
 
-executable getting-started-1
+executable getting-started
-  main-is: GS1.hs
+  main-is: getting-started.hs
+  other-modules: GS1, GS2
   build-depends:
       aeson >= 0.8
     , base >= 4.7
@@ -22,6 +23,7 @@ executable getting-started-1
     , servant
     , servant-server
     , time
+    , wai
     , warp
   hs-source-dirs: getting-started
   default-language: Haskell2010