agent: do not increase network activity interval while offline (#1159)

* agent: do not increase network activity interval while offline

* test

src/Simplex/Messaging/Agent.hs

@@ -429,24 +429,16 @@ getNetworkConfig = fmap snd . readTVarIO . useNetworkConfig
 {-# INLINE getNetworkConfig #-}
 
 setUserNetworkInfo :: AgentClient -> UserNetworkInfo -> IO ()
-setUserNetworkInfo c@AgentClient {userNetworkInfo, userNetworkDelay} netInfo = withAgentEnv' c $ do
-  ni <- asks $ userNetworkInterval . config
-  let d = initialInterval ni
-  off <- atomically $ do
-    wasOnline <- isOnline <$> swapTVar userNetworkInfo netInfo
-    let off = wasOnline && not (isOnline netInfo)
-    when off $ writeTVar userNetworkDelay d
-    pure off
-  liftIO . when off . void . forkIO $
-    growOfflineDelay 0 d ni
+setUserNetworkInfo c@AgentClient {userNetworkInfo, userNetworkUpdated} ni = withAgentEnv' c $ do
+  ts' <- liftIO getCurrentTime
+  i <- asks $ userOfflineDelay . config
+  -- if network offline event happens in less than `userOfflineDelay` after the previous event, it is ignored
+  atomically . whenM ((isOnline ni ||) <$> notRecentlyChanged ts' i) $ do
+    writeTVar userNetworkInfo ni
+    writeTVar userNetworkUpdated $ Just ts'
   where
-    growOfflineDelay elapsed d ni = do
-      online <- waitOnlineOrDelay c d
-      unless online $ do
-        let elapsed' = elapsed + d
-            d' = nextRetryDelay elapsed' d ni
-        atomically $ writeTVar userNetworkDelay d'
-        growOfflineDelay elapsed' d' ni
+    notRecentlyChanged ts' i =
+      maybe True (\ts -> diffUTCTime ts' ts > i) <$> readTVar userNetworkUpdated
 
 reconnectAllServers :: AgentClient -> IO ()
 reconnectAllServers c = do

src/Simplex/Messaging/Agent/Client.hs

@@ -104,7 +104,6 @@ module Simplex.Messaging.Agent.Client
     UserNetworkInfo (..),
     UserNetworkType (..),
     waitForUserNetwork,
-    waitOnlineOrDelay,
     isNetworkOnline,
     isOnline,
     throwWhenInactive,
@@ -155,7 +154,6 @@ import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Either (lefts, partitionEithers)
 import Data.Functor (($>))
-import Data.Int (Int64)
 import Data.List (deleteFirstsBy, foldl', partition, (\\))
 import Data.List.NonEmpty (NonEmpty (..), (<|))
 import qualified Data.List.NonEmpty as L
@@ -270,7 +268,7 @@ data AgentClient = AgentClient
     xftpClients :: TMap XFTPTransportSession XFTPClientVar,
     useNetworkConfig :: TVar (NetworkConfig, NetworkConfig), -- (slow, fast) networks
     userNetworkInfo :: TVar UserNetworkInfo,
-    userNetworkDelay :: TVar Int64,
+    userNetworkUpdated :: TVar (Maybe UTCTime),
     subscrConns :: TVar (Set ConnId),
     activeSubs :: TRcvQueues,
     pendingSubs :: TRcvQueues,
@@ -434,7 +432,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
   xftpClients <- TM.empty
   useNetworkConfig <- newTVar (slowNetworkConfig netCfg, netCfg)
   userNetworkInfo <- newTVar $ UserNetworkInfo UNOther True
-  userNetworkDelay <- newTVar $ initialInterval $ userNetworkInterval cfg
+  userNetworkUpdated <- newTVar Nothing
   subscrConns <- newTVar S.empty
   activeSubs <- RQ.empty
   pendingSubs <- RQ.empty
@@ -470,7 +468,7 @@ newAgentClient clientId InitialAgentServers {smp, ntf, xftp, netCfg} agentEnv =
         xftpClients,
         useNetworkConfig,
         userNetworkInfo,
-        userNetworkDelay,
+        userNetworkUpdated,
         subscrConns,
         activeSubs,
         pendingSubs,
@@ -759,23 +757,9 @@ getNetworkConfig c = do
 
 waitForUserNetwork :: AgentClient -> IO ()
 waitForUserNetwork c =
-  unlessM (atomically $ isNetworkOnline c) $
-    readTVarIO (userNetworkDelay c) >>= void . waitOnlineOrDelay c
-
-waitOnlineOrDelay :: AgentClient -> Int64 -> IO Bool
-waitOnlineOrDelay c t = do
-  let maxWait = min t $ fromIntegral (maxBound :: Int)
-      t' = t - maxWait
-  delay <- registerDelay $ fromIntegral maxWait
-  online <-
-    atomically $ do
-      expired <- readTVar delay
-      online <- isNetworkOnline c
-      unless (expired || online) retry
-      pure online
-  if online || t' <= 0
-    then pure online
-    else waitOnlineOrDelay c t'
+  unlessM (atomically $ isNetworkOnline c) $ do
+    delay <- registerDelay $ userNetworkInterval $ config $ agentEnv c
+    atomically $ unlessM (isNetworkOnline c) $ unlessM (readTVar delay) retry
 
 closeAgentClient :: AgentClient -> IO ()
 closeAgentClient c = do

src/Simplex/Messaging/Agent/Env/SQLite.hs

@@ -92,7 +92,8 @@ data AgentConfig = AgentConfig
     xftpCfg :: XFTPClientConfig,
     reconnectInterval :: RetryInterval,
     messageRetryInterval :: RetryInterval2,
-    userNetworkInterval :: RetryInterval,
+    userNetworkInterval :: Int,
+    userOfflineDelay :: NominalDiffTime,
     messageTimeout :: NominalDiffTime,
     connDeleteDeliveryTimeout :: NominalDiffTime,
     helloTimeout :: NominalDiffTime,
@@ -147,14 +148,6 @@ defaultMessageRetryInterval =
           }
     }
 
-defaultUserNetworkInterval :: RetryInterval
-defaultUserNetworkInterval =
-  RetryInterval
-    { initialInterval = 1200_000000, -- 20 minutes
-      increaseAfter = 0,
-      maxInterval = 7200_000000 -- 2 hours
-    }
-
 defaultAgentConfig :: AgentConfig
 defaultAgentConfig =
   AgentConfig
@@ -170,7 +163,8 @@ defaultAgentConfig =
       xftpCfg = defaultXFTPClientConfig,
       reconnectInterval = defaultReconnectInterval,
       messageRetryInterval = defaultMessageRetryInterval,
-      userNetworkInterval = defaultUserNetworkInterval,
+      userNetworkInterval = 1800_000000, -- 30 minutes, should be less than Int32 max value
+      userOfflineDelay = 2, -- if network offline event happens in less than 2 seconds after it was set online, it is ignored
       messageTimeout = 2 * nominalDay,
       connDeleteDeliveryTimeout = 2 * nominalDay,
       helloTimeout = 2 * nominalDay,
@@ -179,7 +173,7 @@ defaultAgentConfig =
       cleanupInterval = 30 * 60 * 1000000, -- 30 minutes
       cleanupStepInterval = 200000, -- 200ms
       maxWorkerRestartsPerMin = 5,
-      -- 3 consecutive subscription timeouts will result in alert to the user
+      -- 5 consecutive subscription timeouts will result in alert to the user
       -- this is a fallback, as the timeout set to 3x of expected timeout, to avoid potential locking.
       maxSubscriptionTimeouts = 5,
       storedMsgDataTTL = 21 * nominalDay,