Support middleware

servant-effectful.cabal

@@ -58,6 +58,7 @@ library
     , mtl             >=2
     , servant-server  ^>=0.20
     , warp            >=3.3
+    , wai             >=3.2.0
 
 test-suite servant-effectful-test
   import:         common-extensions

src/Effectful/Servant.hs

@@ -21,16 +21,17 @@ import Effectful.Dispatch.Static.Primitive (Env, cloneEnv)
 import Effectful.Error.Static
 import qualified Network.Wai.Handler.Warp as Warp
 import Servant hiding ((:>))
+import qualified Network.Wai as Wai
 
 -- | Deploy an effectful server.
 runWarpServerSettings
   :: forall (api :: Type) (es :: [Effect])
    . (HasServer api '[], IOE :> es)
   => Warp.Settings
   -> ServerT api (Eff (Error ServerError : es))
+  -> Wai.Middleware
   -> Eff es ()
-runWarpServerSettings settings =
-  runWarpServerSettingsContext @api settings EmptyContext
+runWarpServerSettings settings = runWarpServerSettingsContext @api settings EmptyContext
 
 -- | Deploy an effectful server with a context.
 runWarpServerSettingsContext
@@ -39,10 +40,11 @@ runWarpServerSettingsContext
   => Warp.Settings
   -> Context context
   -> ServerT api (Eff (Error ServerError : es))
+  -> Wai.Middleware
   -> Eff es ()
-runWarpServerSettingsContext settings ctx server = do
+runWarpServerSettingsContext settings context server middleware = do
   unsafeEff $ \es -> do
-    Warp.runSettings settings (serveEff @api es ctx server)
+    Warp.runSettings settings (middleware (serveEff @api es context server))
 
 -- | Convert an effectful server into a wai application.
 serveEff