[dispatcher] add timeout for dispatch notifications

I think that sometimes, when user refreshed page, the websocket
connection could hang and the user stopped receiving new
notifications. This is modeled after CentralExchange timeout.

src/Gargantext/Core/Notifications/Dispatcher.hs

@@ -31,16 +31,19 @@ import Data.Aeson qualified as Aeson
 import Data.ByteString.Lazy qualified as BSL
 import Data.Text qualified as T
 import DeferredFolds.UnfoldlM qualified as UnfoldlM
+import Gargantext.Core.Config
+    ( GargConfig, LogConfig, gc_logging, gc_notifications_config )
 import Gargantext.Core.Config.Types (NotificationsConfig(..))
 import Gargantext.Core.Notifications.CentralExchange.Types qualified as CETypes
 import Gargantext.Core.Notifications.Dispatcher.Types
 import Gargantext.Core.Worker.Types (JobInfo(..))
 import Gargantext.Prelude
+import Gargantext.System.Logging
+    ( HasLogger(logMsg), LogLevel(..), withLogger, logLoc )
 import Nanomsg (Pull(..), bind, recv, withSocket)
 import Network.WebSockets qualified as WS
 import StmContainers.Set qualified as SSet
-import Gargantext.Core.Config
-import Gargantext.System.Logging
+import System.Timeout (timeout)
 
 {-
 
@@ -162,13 +165,21 @@ sendNotification throttleTChan ceMessage sub = do
       atomically $ do
         TChan.writeTChan throttleTChan (id', (wsConn ws, WS.Text (Aeson.encode notification) Nothing))
 
+-- | Static send timeout, in microseconds
+sendTimeoutUs :: Int
+sendTimeoutUs = 50_000
+
 -- | The "true" message sending to websocket. After it was withheld
 -- for a while (for throttling), it is finally sent here
 sendDataMessageThrottled :: LogConfig -> (WS.Connection, WS.DataMessage) -> IO ()
 sendDataMessageThrottled log_cfg (conn, msg) = do
-  withLogger log_cfg $ \ioL ->
+  withLogger log_cfg $ \ioL -> do
     logMsg ioL DEBUG $ "[sendDataMessageThrottled] dispatching notification: " <> show msg
-  WS.sendDataMessage conn msg
+    timeoutKickedIn <- timeout sendTimeoutUs $ WS.sendDataMessage conn msg
+    case timeoutKickedIn of
+      Nothing ->
+          $(logLoc) ioL ERROR $ "[sendMessageThrottled] couldn't send msg in timely fashion."
+      Just _ -> pure ()
 
 
 -- | Custom filtering of list of Subscriptions based on