1 files changed, 13 insertions, 3 deletions
diff --git a/lambda-calcul/haskell/src/Minilang/Server.hs b/lambda-calcul/haskell/src/Minilang/Server.hs
index 6f820ed..8dc8c17 100644
--- a/lambda-calcul/haskell/src/Minilang/Server.hs
+++ b/lambda-calcul/haskell/src/Minilang/Server.hs
@@ -1,4 +1,6 @@
 {-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 
 -- | An HTTP server providing a basic REPL and text editor to work
 -- collaboratively on Minilang code.
@@ -10,13 +12,13 @@ import Data.Aeson
   ( Value,
     decode,
     object,
-    (.=),
+    (.=), eitherDecodeFileStrict,
   )
 import Data.ByteString.Lazy (fromStrict)
 import Data.Data (Proxy (..))
 import Data.Default
 import Data.Text (Text)
-import Minilang.API (LambdaAPI)
+import Minilang.API (LambdaAPI, Challenge, defaultChallenges)
 import Minilang.App (Env (..), lambdaApp, runApp, makeEnv)
 import Minilang.Log
 import Minilang.REPL.Net
@@ -28,6 +30,7 @@ import Servant (hoistServer)
 import Servant.Server (serve)
 import System.Log.FastLogger (fromLogStr)
 import System.Random (newStdGen)
+import Control.Exception (IOException, try)
 
 data Server = Server
   { -- | If the server is running, this will contain the underlying
@@ -44,7 +47,8 @@ startServer serverPort = do
   envs <- newTVarIO mempty
   logger <- newLog "minilang"
   loggerMiddleware <- runHTTPLog logger
-  env <- newStdGen >>= makeEnv
+  challenges <- readChallenges
+  env <- newStdGen >>= (`makeEnv` challenges)
   let app =
         loggerMiddleware $
           runNetREPL logger envs (serveAPI env)
@@ -65,6 +69,12 @@ startServer serverPort = do
             destination = Callback (\str -> logInfo logger (decode @Value $ fromStrict $ fromLogStr str))
           }
 
+readChallenges :: IO [Challenge]
+readChallenges = do
+  eitherDecodeFileStrict "challenges.json" >>= \case
+    Right challenges -> pure challenges
+    Left _ -> pure defaultChallenges
+
 serveAPI :: Env -> Application
 serveAPI env =
   serve apiProxy $