From 2ac56d4880d71c598724709cd8f7d4b8ac2ac3d6 Mon Sep 17 00:00:00 2001
From: Philippe Pittoli <karchnu@karchnu.fr>
Date: Wed, 13 Nov 2024 17:57:24 +0100
Subject: [PATCH] Closing connections due to inactiviy: WORKS! \o/

---
 src/App/Container.purs | 35 +++++++++++++++++++++++++++++------
 src/App/WS.purs        | 31 ++++++++++++++++++++++++++++---
 2 files changed, 57 insertions(+), 9 deletions(-)

diff --git a/src/App/Container.purs b/src/App/Container.purs
index 1790ea5..1e7634b 100644
--- a/src/App/Container.purs
+++ b/src/App/Container.purs
@@ -45,7 +45,7 @@
 -- | - mail recovery, password change
 module App.Container where
 
-import Prelude (Unit, bind, discard, unit, ($), (=<<), (<>), show, pure, (+), (&&))
+import Prelude (Unit, bind, discard, unit, ($), (=<<), (<>), show, pure, (+), (&&), (>))
 
 import Bulma as Bulma
 
@@ -94,6 +94,12 @@ type Login = String
 type Password = String
 type LogInfo = Tuple Login Password
 
+-- | A keepalive message is sent every 30 seconds to keep the connection open.
+-- | `max_keepalive` represents the maximum number of keepalive messages
+-- | before closing the connections due to inactivity.
+-- | Current limit is 30 minutes (`max_keepalive` = 60, 60 * 30 seconds = 30 minutes).
+max_keepalive = 60 :: Int
+
 data Action
   = Initialize
 
@@ -374,13 +380,30 @@ handleAction = case _ of
   ResetKeepAliveCounter -> H.modify_ _ { keepalive_counter = 0 }
   KeepAlive auth_or_dnsmanager -> case auth_or_dnsmanager of
     Left _ -> do
-      message <- H.liftEffect $ AuthD.serialize $ AuthD.MkKeepAlive {}
-      H.tell _ws_auth unit (WS.ToSendKeepAlive message)
-      H.modify_ \state -> state { keepalive_counter = state.keepalive_counter + 1 }
+      state <- H.get
+      if state.are_we_connected_to_authd
+      then if (state.keepalive_counter + 1) > max_keepalive
+           then do handleAction $ Log $ SystemLog "Closing the websockets due to inactivity."
+                   H.tell _ws_auth unit (WS.CloseConnection)
+                   H.tell _ws_dns  unit (WS.CloseConnection)
+                   H.modify_ _ { are_we_connected_to_authd = false
+                               , are_we_connected_to_dnsmanagerd = false
+                               --, are_we_closed_due_to_inactiviy = true
+                               }
+           else do message <- H.liftEffect $ AuthD.serialize $ AuthD.MkKeepAlive {}
+                   H.tell _ws_auth unit (WS.ToSendKeepAlive message)
+                   H.modify_ _ { keepalive_counter = state.keepalive_counter + 1 }
+      else do -- handleAction $ Log $ SystemLog "KeepAlive message from WS while connection was closed."
+              pure unit
 
     Right _ -> do
-      message <- H.liftEffect $ DNSManager.serialize $ DNSManager.MkKeepAlive {}
-      H.tell _ws_dns unit (WS.ToSendKeepAlive message)
+      state <- H.get
+      if state.are_we_connected_to_dnsmanagerd
+      then do
+        message <- H.liftEffect $ DNSManager.serialize $ DNSManager.MkKeepAlive {}
+        H.tell _ws_dns unit (WS.ToSendKeepAlive message)
+      else do -- handleAction $ Log $ SystemLog "KeepAlive message from WS while connection was closed."
+              pure unit
 
   AuthenticateToAuthd v -> case v of
     Left token -> do
diff --git a/src/App/WS.purs b/src/App/WS.purs
index aeee90a..6332fb8 100644
--- a/src/App/WS.purs
+++ b/src/App/WS.purs
@@ -36,7 +36,11 @@ import App.Type.LogMessage
 
 import CSSClasses as C
 
-keepalive = 5000.0 :: Number
+-- | Send a keepalive message every 30 seconds, otherwise websockets
+-- | are automatically disconnected. There is a limit in `App.Container`
+-- | named `max_keepalive` to close the connection due to inactivity.
+-- | Current limit is 30 minutes (`max_keepalive` = 60, 60 * 30 seconds = 30 minutes).
+keepalive = 30000.0 :: Number
 
 -- Input is the WS url.
 type Input = (Tuple String String)
@@ -63,7 +67,19 @@ data Output
   | ResetKeepAliveCounter
 
 -- | The component can receive a single action from other components: sending a message throught the websocket.
-data Query a = ToSend ArrayBuffer a | ToSendKeepAlive ArrayBuffer a | Connect a
+data Query a =
+
+  -- | Send a message.
+    ToSend ArrayBuffer a
+
+  -- | Send a keepalive message: do not tell the parent to reset the keepalive counter.
+  | ToSendKeepAlive ArrayBuffer a
+
+  -- | Restarts the connection.
+  | Connect a
+
+  -- | Close connection due to inactivity.
+  | CloseConnection a
 
 type Slot = H.Slot Query Output
 
@@ -223,11 +239,12 @@ handleAction action = do
 
 handleQuery :: forall a m. MonadAff m => Query a -> H.HalogenM State Action () Output m (Maybe a)
 handleQuery = case _ of
+  -- Send a message.
   ToSend message a -> do
     H.raise ResetKeepAliveCounter
     send_message message
     pure (Just a)
-  -- Sending a keepalive: do not tell the parent to reset the keepalive counter.
+  -- Send a keepalive message: do not tell the parent to reset the keepalive counter.
   ToSendKeepAlive message a -> do
     -- In case a KeepAlive is sent while the connection is down, just ignore it.
     state <- H.get
@@ -236,6 +253,7 @@ handleQuery = case _ of
       Just _ -> do
         send_message message
         pure (Just a)
+  -- Restarts the connection.
   Connect a -> do
     state <- H.get
     case state.wsInfo.connection of
@@ -243,6 +261,13 @@ handleQuery = case _ of
         handleAction ConnectWebSocket
         pure (Just a)
       Just _ -> pure Nothing
+  -- Close connection due to inactivity.
+  CloseConnection a -> do
+    { wsInfo } <- H.get
+    case wsInfo.connection of
+      Nothing -> pure unit
+      Just socket -> H.liftEffect $ WS.close socket
+    pure (Just a)
 
 send_message :: forall m. MonadAff m =>
   ArrayBuffer -> H.HalogenM State Action () Output m Unit