Merge pull request #981 from OneSignal/fix/register_user_thread_safe_for_main

Register User Thread Safety Improvement

Author: jkasten2

iOS_SDK/OneSignalSDK/Source/OneSignal.m

@@ -1721,12 +1721,6 @@ + (void)registerUserAfterDelay {
     [OneSignalHelper performSelector:@selector(registerUser) onMainThreadOnObject:self withObject:nil afterDelay:reattemptRegistrationInterval];
 }
 
-static dispatch_queue_t serialQueue;
-
-+ (dispatch_queue_t)getRegisterQueue {
-    return serialQueue;
-}
-
 + (void)registerUser {
     // return if the user has not granted privacy permissions
     if ([self shouldLogMissingPrivacyConsentErrorWithMethodName:nil])
@@ -1737,21 +1731,17 @@ + (void)registerUser {
         return;
     }
 
-    if (!serialQueue)
-        serialQueue = dispatch_queue_create("com.onesignal.regiseruser", DISPATCH_QUEUE_SERIAL);
-
     [self registerUserNow];
 }
 
 +(void)registerUserNow {
     [OneSignal onesignal_Log:ONE_S_LL_VERBOSE message:@"registerUserNow"];
-
-    if (!serialQueue)
-        serialQueue = dispatch_queue_create("com.onesignal.regiseruser", DISPATCH_QUEUE_SERIAL);
 
-    dispatch_async(serialQueue, ^{
+    // Run on the main queue as it is possible for this to be called from multiple queues.
+    // Also some of the code in the method is not thread safe such as _outcomeEventsController.
+    [OneSignalHelper dispatch_async_on_main_queue:^{
         [self registerUserInternal];
-     });
+    }];
 }
 
 // We should delay registration if we are waiting on APNS

iOS_SDK/OneSignalSDK/UnitTests/UnitTestCommonMethods.h

@@ -83,7 +83,6 @@ withNotificationWillShowInForegroundHandler:(OSNotificationWillShowInForegroundB
 
 // Expose OneSignal test methods
 @interface OneSignal (UN_extra)
-+ (dispatch_queue_t) getRegisterQueue;
 + (void)setDelayIntervals:(NSTimeInterval)apnsMaxWait withRegistrationDelay:(NSTimeInterval)registrationDelay;
 @end
 

iOS_SDK/OneSignalSDK/UnitTests/UnitTestCommonMethods.m

@@ -182,18 +182,14 @@ + (void)runBackgroundThreads {
 
 + (void)runThreadsOnEachQueue {
     // the httpQueue makes sure all HTTP request mocks are sync'ed
-    dispatch_queue_t registerUserQueue, notifSettingsQueue;
+    dispatch_queue_t notifSettingsQueue;
 
     [OneSignalHelperOverrider runBackgroundThreads];
 
     notifSettingsQueue = [OneSignalNotificationSettingsIOS10 getQueue];
     if (notifSettingsQueue)
         dispatch_sync(notifSettingsQueue, ^{});
 
-    registerUserQueue = [OneSignal getRegisterQueue];
-    if (registerUserQueue)
-        dispatch_sync(registerUserQueue, ^{});
-    
     [OneSignalClientOverrider runBackgroundThreads];
 
     [UNUserNotificationCenterOverrider runBackgroundThreads];