From de4dfbb2cde75859b632ab018e84725a0fe850f7 Mon Sep 17 00:00:00 2001
From: Doug <douglase@element.io>
Date: Thu, 7 Sep 2023 18:41:33 +0100
Subject: [PATCH 1/2] Stop the sync service constantly attempting to restart on
 auth error.

Additionally removes a retain cycle that was preventing the client from being released.
---
 .../FlowCoordinators/UserSessionFlowCoordinator.swift | 11 ++++++-----
 ElementX/Sources/Services/Client/ClientProxy.swift    |  9 +++++++++
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/ElementX/Sources/FlowCoordinators/UserSessionFlowCoordinator.swift b/ElementX/Sources/FlowCoordinators/UserSessionFlowCoordinator.swift
index 89d68a7a69..dce5ec2cf6 100644
--- a/ElementX/Sources/FlowCoordinators/UserSessionFlowCoordinator.swift
+++ b/ElementX/Sources/FlowCoordinators/UserSessionFlowCoordinator.swift
@@ -73,14 +73,15 @@ class UserSessionFlowCoordinator: FlowCoordinatorProtocol {
         
         setupStateMachine()
         
-        roomFlowCoordinator.actions.sink { action in
+        roomFlowCoordinator.actions.sink { [weak self] action in
+            guard let self else { return }
             switch action {
             case .presentedRoom(let roomID):
-                self.analytics.signpost.beginRoomFlow(roomID)
-                self.stateMachine.processEvent(.selectRoom(roomID: roomID))
+                analytics.signpost.beginRoomFlow(roomID)
+                stateMachine.processEvent(.selectRoom(roomID: roomID))
             case .dismissedRoom:
-                self.stateMachine.processEvent(.deselectRoom)
-                self.analytics.signpost.endRoomFlow()
+                stateMachine.processEvent(.deselectRoom)
+                analytics.signpost.endRoomFlow()
             }
         }
         .store(in: &cancellables)
diff --git a/ElementX/Sources/Services/Client/ClientProxy.swift b/ElementX/Sources/Services/Client/ClientProxy.swift
index 34cc03d2a2..31a0ec831a 100644
--- a/ElementX/Sources/Services/Client/ClientProxy.swift
+++ b/ElementX/Sources/Services/Client/ClientProxy.swift
@@ -54,6 +54,11 @@ class ClientProxy: ClientProxyProtocol {
     private var cancellables = Set<AnyCancellable>()
     private var visibleRoomsListProxyStateObservationToken: AnyCancellable?
     
+    /// Will be `true` whilst the app cleans up and forces a logout. Prevents the sync service from restarting
+    /// before the client is released which ends up running in a loop. This is a workaround until the sync service
+    /// can tell us *what* error occurred so we can handle restarts more gracefully.
+    private var hasEncounteredAuthError = false
+    
     deinit {
         client.setDelegate(delegate: nil)
         stopSync()
@@ -79,6 +84,7 @@ class ClientProxy: ClientProxyProtocol {
                                                          backgroundTaskService: backgroundTaskService)
 
         client.setDelegate(delegate: ClientDelegateWrapper { [weak self] isSoftLogout in
+            self?.hasEncounteredAuthError = true
             self?.callbacks.send(.receivedAuthError(isSoftLogout: isSoftLogout))
         } tokenRefreshCallback: { [weak self] in
             self?.callbacks.send(.updateRestorationToken)
@@ -125,6 +131,8 @@ class ClientProxy: ClientProxyProtocol {
     }
 
     func startSync() {
+        guard !hasEncounteredAuthError else { return }
+        
         MXLog.info("Starting sync")
         
         Task {
@@ -372,6 +380,7 @@ class ClientProxy: ClientProxyProtocol {
                 MXLog.error("Failed restarting the sync service with error: \(error)")
             }
             
+            guard !hasEncounteredAuthError else { return }
             await self.syncService?.start()
         }
     }

From c6670176f7e122d90a018b0e9cc4cfaed9670243 Mon Sep 17 00:00:00 2001
From: Doug <douglase@element.io>
Date: Fri, 8 Sep 2023 10:24:40 +0100
Subject: [PATCH 2/2] Remove restartSync.

The SDK has changed a lot, we no longer need to stop and start the sync loop.
---
 .../Sources/Services/Client/ClientProxy.swift | 23 ++++---------------
 1 file changed, 5 insertions(+), 18 deletions(-)

diff --git a/ElementX/Sources/Services/Client/ClientProxy.swift b/ElementX/Sources/Services/Client/ClientProxy.swift
index 31a0ec831a..44bfd21653 100644
--- a/ElementX/Sources/Services/Client/ClientProxy.swift
+++ b/ElementX/Sources/Services/Client/ClientProxy.swift
@@ -131,7 +131,10 @@ class ClientProxy: ClientProxyProtocol {
     }
 
     func startSync() {
-        guard !hasEncounteredAuthError else { return }
+        guard !hasEncounteredAuthError else {
+            MXLog.warning("Ignoring request, this client has an unknown token.")
+            return
+        }
         
         MXLog.info("Starting sync")
         
@@ -368,22 +371,6 @@ class ClientProxy: ClientProxyProtocol {
     }
     
     // MARK: Private
-    
-    private func restartSync(delay: Duration = .zero) {
-        Task {
-            try await Task.sleep(for: delay)
-            
-            do {
-                MXLog.info("Restarting the sync service.")
-                try await self.syncService?.stop()
-            } catch {
-                MXLog.error("Failed restarting the sync service with error: \(error)")
-            }
-            
-            guard !hasEncounteredAuthError else { return }
-            await self.syncService?.start()
-        }
-    }
 
     private func loadUserAvatarURLFromCache() {
         loadCachedAvatarURLTask = Task {
@@ -451,7 +438,7 @@ class ClientProxy: ClientProxyProtocol {
             case .running, .terminated, .idle:
                 break
             case .error:
-                restartSync()
+                startSync()
             }
         })
     }