Drop vestigial FileSystem effect requirement

src/Core.hs

@@ -11,9 +11,7 @@ import Database.PostgreSQL.Simple.FromRow   (FromRow, field, fromRow)
 import Database.PostgreSQL.Simple.ToField   (ToField, toField)
 import Database.PostgreSQL.Simple.ToRow     (ToRow, toRow)
 import Effectful
-import Effectful.Dispatch.Dynamic
 import Effectful.Error.Static               (Error, throwError)
-import Effectful.FileSystem                 (FileSystem)
 import Effectful.Reader.Static              (Reader)
 import GHC.Generics                         (Generic)
 import Servant hiding                       ((:>), throwError)
@@ -21,8 +19,7 @@ import Servant hiding                       ((:>), throwError)
 --
 -- Core data types
 --
-type AppEff = Eff '[ FileSystem
-                   , Logger
+type AppEff = Eff '[ Logger
                    , Database
                    , Reader AppEnv
                    , Error ServerError
@@ -51,6 +48,8 @@ instance ToJSON User
 instance FromJSON User
 
 data Database :: Effect where
+  DatabaseInit
+    :: Database (Eff es) ()
   DatabaseRead
     :: (ToField a, Show a, FromRow b) => (Query, a) -> Database (Eff es) [b]
   DatabaseRead_

src/Database.hs

@@ -38,7 +38,7 @@ databaseWrite
 databaseWrite = send . DatabaseWrite
 
 runDatabaseDebug :: DatabaseExeEffects es => Eff (Database : es) a -> Eff es a
-runDatabaseDebug = interpret $ \_ -> \case
+runDatabaseDebug = interpret $ \ -> \case
   DatabaseRead  (statement, values) -> do
     liftIOE $ putStrLn
        $ "Mocked a READ database operation with statement:\n"

src/Handlers.hs

@@ -9,8 +9,6 @@ import Data.List
 import qualified Data.Text                as T
 import Effectful
 import Effectful.Error.Static             (Error, throwError)
-import Effectful.FileSystem
-import Effectful.FileSystem.IO.ByteString as EBS
 import Servant hiding                     ((:>), throwError)
 import qualified Servant                  as S
 
@@ -21,7 +19,7 @@ rootHandler = (writeLog Info "Hit the root!") >>= \_ ->
   return "Hello, World!"
 
 userListHandler :: CRUD es => Eff es [User]
-userListHandler = (writeLog Info "Selected all users!") >>= \_ -> 
+userListHandler = (writeLog Info "Selected all users!") >>= \_ ->
   databaseRead_ "SELECT id, name FROM users"
 
 userGetHandler :: CRUD es => UserId -> Eff es User

src/Logger.hs

@@ -7,7 +7,6 @@ import Data.Time                  (getCurrentTime, UTCTime)
 import Effectful
 import Effectful.Dispatch.Dynamic
 import Effectful.Error.Static     (Error, throwError)
-import Effectful.FileSystem
 import Effectful.Reader.Static
 import GHC.Generics                (Generic)
 import Servant                     hiding ((:>))

src/Main.hs

@@ -10,7 +10,6 @@ import Control.Monad.Except     (ExceptT (ExceptT))
 import Data.List
 import Effectful
 import Effectful.Error.Static   (Error, runErrorNoCallStack, throwError)
-import Effectful.FileSystem
 import Effectful.Reader.Static
 import Network.Wai.Handler.Warp (run)
 import Servant hiding           ((:>), throwError)
@@ -23,7 +22,7 @@ main :: IO ()
 main = do
   pool <- createConnectionPool
   let env = AppEnv { pool = pool }
-  run port $ serve proxy $ app env
+  run port . serve proxy $ app env
 
 app :: AppEnv -> Server AppAPI
 app env = transformEff env
@@ -42,7 +41,6 @@ transformEff env = hoistServer proxy
   . runReader env
   . runDatabaseIO
   . runLoggerPSQL
-  . runFileSystem
 
 port :: Int
 port = 8080