Rework the “disappearing messages” logic.

// FREEBIE

Signal.xcodeproj/project.pbxproj

@@ -68,7 +68,6 @@
 		34B3F89F1E8DF5490035BE1A /* OWSTableViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 34B3F89E1E8DF5490035BE1A /* OWSTableViewController.m */; };
 		34B3F8A21E8EA6040035BE1A /* ViewControllerUtils.m in Sources */ = {isa = PBXBuildFile; fileRef = 34B3F8A11E8EA6040035BE1A /* ViewControllerUtils.m */; };
 		34D5CC961EA6AFAD005515DB /* OWSContactsSyncing.m in Sources */ = {isa = PBXBuildFile; fileRef = 34D5CC951EA6AFAD005515DB /* OWSContactsSyncing.m */; };
-		34D5CCA61EA934A4005515DB /* NSTimer+OWS.m in Sources */ = {isa = PBXBuildFile; fileRef = 34D5CCA51EA934A4005515DB /* NSTimer+OWS.m */; };
 		34D5CCA91EAE3D30005515DB /* GroupViewHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = 34D5CCA81EAE3D30005515DB /* GroupViewHelper.m */; };
 		34D5CCB11EAE7E7F005515DB /* SelectRecipientViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 34D5CCB01EAE7E7F005515DB /* SelectRecipientViewController.m */; };
 		34DFCB851E8E04B500053165 /* AddToBlockListViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 34DFCB841E8E04B500053165 /* AddToBlockListViewController.m */; };
@@ -452,8 +451,8 @@
 		34B3F86E1E8DF1700035BE1A /* SignalsNavigationController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SignalsNavigationController.m; sourceTree = "<group>"; };
 		34B3F86F1E8DF1700035BE1A /* SignalsViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SignalsViewController.h; sourceTree = "<group>"; };
 		34B3F8701E8DF1700035BE1A /* SignalsViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SignalsViewController.m; sourceTree = "<group>"; };
-		34B3F89A1E8DF3270035BE1A /* BlockListViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = BlockListViewController.h; sourceTree = "<group>"; };
 		34B3F8981E8DF1B90035BE1A /* TSMessageAdapterTest.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = TSMessageAdapterTest.m; sourceTree = "<group>"; };
+		34B3F89A1E8DF3270035BE1A /* BlockListViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = BlockListViewController.h; sourceTree = "<group>"; };
 		34B3F89B1E8DF3270035BE1A /* BlockListViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = BlockListViewController.m; sourceTree = "<group>"; };
 		34B3F89D1E8DF5490035BE1A /* OWSTableViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OWSTableViewController.h; sourceTree = "<group>"; };
 		34B3F89E1E8DF5490035BE1A /* OWSTableViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OWSTableViewController.m; sourceTree = "<group>"; };
@@ -463,8 +462,6 @@
 		34D5CC951EA6AFAD005515DB /* OWSContactsSyncing.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OWSContactsSyncing.m; sourceTree = "<group>"; };
 		34D5CC981EA6EB79005515DB /* OWSMessageCollectionViewCell.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OWSMessageCollectionViewCell.h; sourceTree = "<group>"; };
 		34D5CC9B1EA6ED17005515DB /* OWSMessageMediaAdapter.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OWSMessageMediaAdapter.h; sourceTree = "<group>"; };
-		34D5CCA41EA934A4005515DB /* NSTimer+OWS.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "NSTimer+OWS.h"; sourceTree = "<group>"; };
-		34D5CCA51EA934A4005515DB /* NSTimer+OWS.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "NSTimer+OWS.m"; sourceTree = "<group>"; };
 		34D5CCA71EAE3D30005515DB /* GroupViewHelper.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = GroupViewHelper.h; sourceTree = "<group>"; };
 		34D5CCA81EAE3D30005515DB /* GroupViewHelper.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GroupViewHelper.m; sourceTree = "<group>"; };
 		34D5CCAB1EAE7136005515DB /* OWSConversationSettingsViewDelegate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OWSConversationSettingsViewDelegate.h; sourceTree = "<group>"; };
@@ -1249,8 +1246,6 @@
 				76EB04EB18170B33006006FC /* FunctionalUtil.m */,
 				B62F5E0E1C2980B4000D370C /* NSData+ows_StripToken.h */,
 				B62F5E0F1C2980B4000D370C /* NSData+ows_StripToken.m */,
-				34D5CCA41EA934A4005515DB /* NSTimer+OWS.h */,
-				34D5CCA51EA934A4005515DB /* NSTimer+OWS.m */,
 				76EB04EC18170B33006006FC /* NumberUtil.h */,
 				76EB04ED18170B33006006FC /* NumberUtil.m */,
 				BFB074C519A5611000F2947C /* ObservableValue.h */,
@@ -2120,7 +2115,6 @@
 				34B3F88D1E8DF1700035BE1A /* OWSQRCodeScanningViewController.m in Sources */,
 				34B3F8811E8DF1700035BE1A /* LockInteractionController.m in Sources */,
 				45F659731E1BD99C00444429 /* CallKitCallUIAdaptee.swift in Sources */,
-				34D5CCA61EA934A4005515DB /* NSTimer+OWS.m in Sources */,
 				45BB93381E688E14001E3939 /* UIDevice+featureSupport.swift in Sources */,
 				458DE9D61DEE3FD00071BB03 /* PeerConnectionClient.swift in Sources */,
 				451DE9FD1DC1A28200810E42 /* SyncPushTokensJob.swift in Sources */,

Signal/src/AppDelegate.m

@@ -153,8 +153,9 @@ static NSString *const kURLHostVerifyPrefix             = @"verify";
                                              preferences:[Environment preferences]
                                               showAlerts:NO];
 
-                // Clean up any messages that expired since last launch.
+                // Clean up any messages that expired since last launch immediately
-                [[[OWSDisappearingMessagesJob alloc] initWithStorageManager:[TSStorageManager sharedManager]] run];
+                // and continue cleaning in the background.
+                [[OWSDisappearingMessagesJob sharedJob] startIfNecessary];
 
                 // Mark all "attempting out" messages as "unsent", i.e. any messages that were not successfully
                 // sent before the app exited should be marked as failures.

Signal/src/ViewControllers/MessagesViewController.m

@@ -12,7 +12,6 @@
 #import "FingerprintViewController.h"
 #import "FullImageViewController.h"
 #import "NSDate+millisecondTimeStamp.h"
-#import "NSTimer+OWS.h"
 #import "NewGroupViewController.h"
 #import "OWSAudioAttachmentPlayer.h"
 #import "OWSCall.h"
@@ -61,6 +60,7 @@
 #import <MobileCoreServices/UTCoreTypes.h>
 #import <SignalServiceKit/ContactsUpdater.h>
 #import <SignalServiceKit/MimeTypeUtil.h>
+#import <SignalServiceKit/NSTimer+OWS.h>
 #import <SignalServiceKit/OWSAttachmentsProcessor.h>
 #import <SignalServiceKit/OWSBlockingManager.h>
 #import <SignalServiceKit/OWSDisappearingMessagesConfiguration.h>
@@ -557,7 +557,6 @@ typedef enum : NSUInteger {
 @property (nonatomic, readonly) ContactsUpdater *contactsUpdater;
 @property (nonatomic, readonly) OWSMessageSender *messageSender;
 @property (nonatomic, readonly) TSStorageManager *storageManager;
-@property (nonatomic, readonly) OWSDisappearingMessagesJob *disappearingMessagesJob;
 @property (nonatomic, readonly) TSMessagesManager *messagesManager;
 @property (nonatomic, readonly) TSNetworkManager *networkManager;
 @property (nonatomic, readonly) OutboundCallInitiator *outboundCallInitiator;
@@ -617,7 +616,6 @@ typedef enum : NSUInteger {
     _messageSender = [Environment getCurrent].messageSender;
     _outboundCallInitiator = [Environment getCurrent].outboundCallInitiator;
     _storageManager = [TSStorageManager sharedManager];
-    _disappearingMessagesJob = [[OWSDisappearingMessagesJob alloc] initWithStorageManager:_storageManager];
     _messagesManager = [TSMessagesManager sharedManager];
     _networkManager = [TSNetworkManager sharedManager];
     _blockingManager = [OWSBlockingManager sharedManager];
@@ -3257,9 +3255,10 @@ typedef enum : NSUInteger {
 - (void)markAllMessagesAsRead
 {
     [self.thread markAllAsRead];
+
     // In theory this should be unnecessary as read-status starts expiration
     // but in practice I've seen messages not have their timer started.
-    [self.disappearingMessagesJob setExpirationsForThread:self.thread];
+    [OWSDisappearingMessagesJob setExpirationsForThread:self.thread];
 }
 
 - (BOOL)collectionView:(UICollectionView *)collectionView

Signal/src/ViewControllers/OWSAudioAttachmentPlayer.m

@@ -3,11 +3,11 @@
 //
 
 #import "OWSAudioAttachmentPlayer.h"
-#import "NSTimer+OWS.h"
 #import "TSAttachment.h"
 #import "TSAttachmentStream.h"
 #import "TSVideoAttachmentAdapter.h"
 #import "ViewControllerUtils.h"
+#import <SignalServiceKit/NSTimer+OWS.h>
 #import <YapDatabase/YapDatabaseConnection.h>
 
 NS_ASSUME_NONNULL_BEGIN

Signal/src/ViewControllers/SignalsViewController.m

@@ -19,6 +19,7 @@
 #import "UIUtil.h"
 #import "VersionMigrations.h"
 #import <SignalServiceKit/OWSBlockingManager.h>
+#import <SignalServiceKit/OWSDisappearingMessagesJob.h>
 #import <SignalServiceKit/OWSMessageSender.h>
 #import <SignalServiceKit/TSMessagesManager.h>
 #import <SignalServiceKit/TSOutgoingMessage.h>
@@ -318,6 +319,10 @@ NSString *const SignalsViewControllerSegueShowIncomingCall = @"ShowIncomingCallS
             [self.experienceUpgradeFinder markAllAsSeenWithTransaction:transaction];
         }];
         [self ensureNotificationsUpToDate];
+
+        // Clean up any messages that expired since last launch immediately
+        // and continue cleaning in the background.
+        [[OWSDisappearingMessagesJob sharedJob] startIfNecessary];
     } else {
         [self displayAnyUnseenUpgradeExperience];
     }

Signal/src/util/NSTimer+OWS.h

@@ -1,19 +0,0 @@
-//
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
-//
-
-NS_ASSUME_NONNULL_BEGIN
-
-@interface NSTimer (OWS)
-
-// This method avoids the classic NSTimer retain cycle bug
-// by using a weak reference to the target.
-+ (NSTimer *)weakScheduledTimerWithTimeInterval:(NSTimeInterval)timeInterval
-                                         target:(id)target
-                                       selector:(SEL)selector
-                                       userInfo:(nullable id)userInfo
-                                        repeats:(BOOL)repeats;
-
-@end
-
-NS_ASSUME_NONNULL_END

Signal/src/util/NSTimer+OWS.m

@@ -1,69 +0,0 @@
-//
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
-//
-
-#import "NSTimer+OWS.h"
-#import <objc/runtime.h>
-
-NS_ASSUME_NONNULL_BEGIN
-
-@interface NSTimerProxy : NSObject
-
-@property (nonatomic, weak) id target;
-@property (nonatomic) SEL selector;
-
-@end
-
-#pragma mark -
-
-@implementation NSTimerProxy
-
-- (void)timerFired:(NSDictionary *)userInfo
-{
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
-    [self.target performSelector:self.selector withObject:userInfo];
-#pragma clang diagnostic pop
-}
-
-@end
-
-#pragma mark -
-
-static void *kNSTimer_OWS_Proxy = &kNSTimer_OWS_Proxy;
-
-@implementation NSTimer (OWS)
-
-- (NSTimerProxy *)ows_proxy
-{
-    return objc_getAssociatedObject(self, kNSTimer_OWS_Proxy);
-}
-
-- (void)ows_setProxy:(NSTimerProxy *)proxy
-{
-    OWSAssert(proxy);
-
-    objc_setAssociatedObject(self, kNSTimer_OWS_Proxy, proxy, OBJC_ASSOCIATION_RETAIN);
-}
-
-+ (NSTimer *)weakScheduledTimerWithTimeInterval:(NSTimeInterval)timeInterval
-                                         target:(id)target
-                                       selector:(SEL)selector
-                                       userInfo:(nullable id)userInfo
-                                        repeats:(BOOL)repeats
-{
-    NSTimerProxy *proxy = [NSTimerProxy new];
-    proxy.target = target;
-    proxy.selector = selector;
-    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:timeInterval
-                                                      target:proxy
-                                                    selector:@selector(timerFired:)
-                                                    userInfo:userInfo
-                                                     repeats:repeats];
-    [timer ows_setProxy:proxy];
-    return timer;
-}
-
-@end
-
-NS_ASSUME_NONNULL_END