fix: suppress exceptions relating to expired sessions

src/Application.hs

@@ -98,6 +98,8 @@ import qualified Web.ServerSession.Backend.Acid as Acid
 import qualified Ldap.Client as Ldap (Host(Plain, Tls))
 
 import qualified Network.Minio as Minio
+  
+import Web.ServerSession.Core (StorageException(..))
 
 -- Import all relevant handler modules here.
 -- (HPack takes care to add new modules to our cabal file nowadays.)
@@ -433,7 +435,7 @@ warpSettings foundation = defaultSettings
     & setHost (foundation ^. _appHost)
     & setPort (foundation ^. _appPort)
     & setOnException (\_req e ->
-        when (defaultShouldDisplayException e) $ do
+        when (shouldDisplayException e) $ do
           logger <- readTVarIO . snd $ appLogger foundation
           messageLoggerSource
             foundation
@@ -443,6 +445,16 @@ warpSettings foundation = defaultSettings
             LevelError
             (toLogStr $ "Exception from Warp: " ++ show e)
                      )
+  where
+    shouldDisplayException e = and
+      [ defaultShouldDisplayException e
+      , case fromException e of
+          Just (SessionDoesNotExist{} :: StorageException (MemcachedSqlStorage SessionMap)) -> False
+          _other -> True
+      , case fromException e of
+          Just (SessionDoesNotExist{} :: StorageException (AcidStorage SessionMap)) -> False
+          _other -> True
+      ]
                            
 
 getAppDevSettings, getAppSettings :: MonadIO m => m AppSettings