Flush multi-process writes more aggressively.

Signal/src/AppDelegate.m

@@ -1237,6 +1237,8 @@ static NSTimeInterval launchStartedAt;
 
     [self preheatDatabaseViews];
 
+    [self.primaryStorage touchDbAsync];
+
     // Try to update account attributes every time we upgrade.
     if ([self.tsAccountManager isRegistered]) {
         AppVersion *appVersion = AppVersion.sharedInstance;

Signal/src/ViewControllers/ConversationView/ConversationViewModel.m

@@ -337,6 +337,42 @@ static const int kYapDatabaseRangeMaxLength = 25000;
 - (void)viewDidLoad
 {
     [self addNotificationListeners];
+
+    [self touchDbAsync];
+}
+
+- (void)touchDbAsync
+{
+    // See comments in primaryStorage.touchDbAsync.
+    [self.primaryStorage touchDbAsync];
+
+    id<ConversationViewItem> _Nullable firstViewItem = self.viewItems.firstObject;
+    if (firstViewItem) {
+        __weak ConversationViewModel *weakSelf = self;
+        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.15 * NSEC_PER_SEC)),
+            dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),
+            ^{
+                ConversationViewModel *_Nullable strongSelf = weakSelf;
+                if (!strongSelf) {
+                    return;
+                }
+                if (CurrentAppContext().reportedApplicationState == UIApplicationStateBackground) {
+                    return;
+                }
+                [strongSelf.editingDatabaseConnection
+                    readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+                        // Reload the interaction to ensure it still exists.
+                        TSInteraction *_Nullable interaction =
+                            [TSInteraction fetchObjectWithUniqueID:firstViewItem.interaction.uniqueId
+                                                       transaction:transaction];
+                        if (!interaction) {
+                            // Interaction appears to have been deleted.
+                            return;
+                        }
+                        [interaction touchWithTransaction:transaction];
+                    }];
+            });
+    }
 }
 
 - (void)dealloc
@@ -963,22 +999,8 @@ static const int kYapDatabaseRangeMaxLength = 25000;
     [self.delegate conversationViewModelDidUpdate:ConversationUpdate.reloadUpdate];
 }
 
-- (void)touchDbAsync
-{
-    OWSLogInfo(@"");
-
-    // There appears to be a bug in YapDatabase that sometimes delays modifications
-    // made in another process (e.g. the SAE) from showing up in other processes.
-    // There's a simple workaround: a trivial write to the database flushes changes
-    // made from other processes.
-    [self.editingDatabaseConnection asyncReadWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
-        [transaction setObject:[NSUUID UUID].UUIDString forKey:@"conversation_view_noop_mod" inCollection:@"temp"];
-    }];
-}
-
 - (void)applicationWillEnterForeground:(NSNotification *)notification
 {
-    // See comments in touchDbAsync.
     [self touchDbAsync];
 }
 

SignalServiceKit/src/Storage/OWSPrimaryStorage.h

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2019 Open Whisper Systems. All rights reserved.
 //
 
 #import "OWSStorage.h"
@@ -42,6 +42,10 @@ extern NSString *const OWSUIDatabaseConnectionNotificationsKey;
 
 + (void)protectFiles;
 
+#pragma mark - Misc.
+
+- (void)touchDbAsync;
+
 @end
 
 NS_ASSUME_NONNULL_END

SignalServiceKit/src/Storage/OWSPrimaryStorage.m

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2019 Open Whisper Systems. All rights reserved.
 //
 
 #import "OWSPrimaryStorage.h"
@@ -431,6 +431,21 @@ void VerifyRegistrationsForPrimaryStorage(OWSStorage *storage)
     return OWSPrimaryStorage.sharedManager.dbReadWriteConnection;
 }
 
+#pragma mark - Misc.
+
+- (void)touchDbAsync
+{
+    OWSLogInfo(@"");
+
+    // There appears to be a bug in YapDatabase that sometimes delays modifications
+    // made in another process (e.g. the SAE) from showing up in other processes.
+    // There's a simple workaround: a trivial write to the database flushes changes
+    // made from other processes.
+    [self.dbReadWriteConnection asyncReadWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
+        [transaction setObject:[NSUUID UUID].UUIDString forKey:@"conversation_view_noop_mod" inCollection:@"temp"];
+    }];
+}
+
 @end
 
 NS_ASSUME_NONNULL_END