Use MainThreadOperation to prevent article status updates from interleaving

Frameworks/Account/Account.xcodeproj/project.pbxproj

@@ -89,6 +89,9 @@
 		51E4DB302426353D0091EB5B /* CloudKitAccountZone.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51E4DB2F2426353D0091EB5B /* CloudKitAccountZone.swift */; };
 		51E59599228C77BC00FCC42B /* FeedbinUnreadEntry.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51E59598228C77BC00FCC42B /* FeedbinUnreadEntry.swift */; };
 		51E5959B228C781500FCC42B /* FeedbinStarredEntry.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51E5959A228C781500FCC42B /* FeedbinStarredEntry.swift */; };
+		51F6C58F245DB2E8001E41CA /* CloudKitSendStatusOperation.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51F6C58E245DB2E8001E41CA /* CloudKitSendStatusOperation.swift */; };
+		51F6C591245DB302001E41CA /* CloudKitReceiveStatusOperation.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51F6C590245DB302001E41CA /* CloudKitReceiveStatusOperation.swift */; };
+		51F6C593245DBA8E001E41CA /* CloudKitRemoteNotificationOperation.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51F6C592245DBA8E001E41CA /* CloudKitRemoteNotificationOperation.swift */; };
 		552032F8229D5D5A009559E0 /* ReaderAPIEntry.swift in Sources */ = {isa = PBXBuildFile; fileRef = 552032ED229D5D5A009559E0 /* ReaderAPIEntry.swift */; };
 		552032F9229D5D5A009559E0 /* ReaderAPISubscription.swift in Sources */ = {isa = PBXBuildFile; fileRef = 552032EE229D5D5A009559E0 /* ReaderAPISubscription.swift */; };
 		552032FB229D5D5A009559E0 /* ReaderAPITag.swift in Sources */ = {isa = PBXBuildFile; fileRef = 552032F0229D5D5A009559E0 /* ReaderAPITag.swift */; };
@@ -340,6 +343,9 @@
 		51E4DB2F2426353D0091EB5B /* CloudKitAccountZone.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CloudKitAccountZone.swift; sourceTree = "<group>"; };
 		51E59598228C77BC00FCC42B /* FeedbinUnreadEntry.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedbinUnreadEntry.swift; sourceTree = "<group>"; };
 		51E5959A228C781500FCC42B /* FeedbinStarredEntry.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedbinStarredEntry.swift; sourceTree = "<group>"; };
+		51F6C58E245DB2E8001E41CA /* CloudKitSendStatusOperation.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CloudKitSendStatusOperation.swift; sourceTree = "<group>"; };
+		51F6C590245DB302001E41CA /* CloudKitReceiveStatusOperation.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CloudKitReceiveStatusOperation.swift; sourceTree = "<group>"; };
+		51F6C592245DBA8E001E41CA /* CloudKitRemoteNotificationOperation.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CloudKitRemoteNotificationOperation.swift; sourceTree = "<group>"; };
 		552032ED229D5D5A009559E0 /* ReaderAPIEntry.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ReaderAPIEntry.swift; sourceTree = "<group>"; };
 		552032EE229D5D5A009559E0 /* ReaderAPISubscription.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ReaderAPISubscription.swift; sourceTree = "<group>"; };
 		552032F0229D5D5A009559E0 /* ReaderAPITag.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ReaderAPITag.swift; sourceTree = "<group>"; };
@@ -555,10 +561,13 @@
 				5103A9D82422546800410853 /* CloudKitAccountDelegate.swift */,
 				51E4DB2F2426353D0091EB5B /* CloudKitAccountZone.swift */,
 				512DD4CC2431098700C17B1F /* CloudKitAccountZoneDelegate.swift */,
+				5139A6372459822D004D960C /* CloudKitArticleStatusUpdate.swift */,
 				519E84A72434C5EF00D238B0 /* CloudKitArticlesZone.swift */,
 				519E84AB2435019100D238B0 /* CloudKitArticlesZoneDelegate.swift */,
 				5150FFFD243823B800C1A442 /* CloudKitError.swift */,
-				5139A6372459822D004D960C /* CloudKitArticleStatusUpdate.swift */,
+				51F6C590245DB302001E41CA /* CloudKitReceiveStatusOperation.swift */,
+				51F6C592245DBA8E001E41CA /* CloudKitRemoteNotificationOperation.swift */,
+				51F6C58E245DB2E8001E41CA /* CloudKitSendStatusOperation.swift */,
 				51E4DB2D242633ED0091EB5B /* CloudKitZone.swift */,
 				51C034DE242D65D20014DC71 /* CloudKitZoneResult.swift */,
 			);
@@ -1137,6 +1146,7 @@
 				9EC688EE232C58E800A8D0A2 /* OAuthAuthorizationCodeGranting.swift in Sources */,
 				9EEAE071235D019B00E3FEE4 /* FeedlyGetStreamContentsService.swift in Sources */,
 				9E7299D9235062A200DAEFB7 /* FeedlyResourceProviding.swift in Sources */,
+				51F6C591245DB302001E41CA /* CloudKitReceiveStatusOperation.swift in Sources */,
 				9E672394236F7CA0000BE141 /* FeedlyRefreshAccessTokenOperation.swift in Sources */,
 				514BF5202391B0DB00902FE8 /* SingleArticleFetcher.swift in Sources */,
 				9EC688EC232C583300A8D0A2 /* FeedlyAccountDelegate+OAuth.swift in Sources */,
@@ -1176,6 +1186,7 @@
 				519E84A62433D49000D238B0 /* OPMLNormalizer.swift in Sources */,
 				9EEEF71F23545CB4009E9D80 /* FeedlySendArticleStatusesOperation.swift in Sources */,
 				9EBD49C223C67784005AD5CD /* FeedlyEntryIdentifierProviding.swift in Sources */,
+				51F6C593245DBA8E001E41CA /* CloudKitRemoteNotificationOperation.swift in Sources */,
 				846E77541F6F00E300A165E2 /* AccountManager.swift in Sources */,
 				51E490362288C37100C791F0 /* FeedbinDate.swift in Sources */,
 				9EEAE06E235D002D00E3FEE4 /* FeedlyGetCollectionsService.swift in Sources */,
@@ -1280,6 +1291,7 @@
 				179DBD4ECC1C9712DF51DB8C /* NewsBlurFolderChange.swift in Sources */,
 				179DBCB4B11C88EBE852A015 /* NewsBlurFeedChange.swift in Sources */,
 				179DBE829FDF48E102F73244 /* NewsBlurAccountDelegate+Internal.swift in Sources */,
+				51F6C58F245DB2E8001E41CA /* CloudKitSendStatusOperation.swift in Sources */,
 				179DB3A93E3205EF29C2AF62 /* NewsBlurAPICaller+Internal.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

Frameworks/Account/CloudKit/CloudKitAccountDelegate.swift

@@ -18,9 +18,15 @@ import ArticlesDatabase
 import RSWeb
 import Secrets
 
-public enum CloudKitAccountDelegateError: String, Error {
+enum CloudKitAccountDelegateError: LocalizedError {
-	case invalidParameter = "An invalid parameter was used."
+	case invalidParameter
+	case unknown
+	
+	var errorDescription: String? {
+		return NSLocalizedString("An unexpected CloudKit error occurred.", comment: "An unexpected CloudKit error occurred.")
 	}
+}
+
 
 final class CloudKitAccountDelegate: AccountDelegate {
 
@@ -33,10 +39,11 @@ final class CloudKitAccountDelegate: AccountDelegate {
 		return CKContainer(identifier: "iCloud.\(orgID).NetNewsWire")
 	}()
 	
-	private lazy var zones: [CloudKitZone] = [accountZone, articlesZone]
 	private let accountZone: CloudKitAccountZone
 	private let articlesZone: CloudKitArticlesZone
 	
+	private let mainThreadOperationQueue = MainThreadOperationQueue()
+
 	private lazy var refresher: LocalAccountRefresher = {
 		let refresher = LocalAccountRefresher()
 		refresher.delegate = self
@@ -63,21 +70,11 @@ final class CloudKitAccountDelegate: AccountDelegate {
 	}
 	
 	func receiveRemoteNotification(for account: Account, userInfo: [AnyHashable : Any], completion: @escaping () -> Void) {
-		os_log(.debug, log: log, "Processing remote notification...")
+		let op = CloudKitRemoteNotificationOperation(accountZone: accountZone, articlesZone: articlesZone, userInfo: userInfo)
-
+		op.completionBlock = { mainThreadOperaion in
-		let group = DispatchGroup()
-		
-		zones.forEach { zone in
-			group.enter()
-			zone.receiveRemoteNotification(userInfo: userInfo) {
-				group.leave()
-			}
-		}
-		
-		group.notify(queue: DispatchQueue.main) {
-			os_log(.debug, log: self.log, "Done processing remote notification...")
 			completion()
 		}
+		mainThreadOperationQueue.add(op)
 	}
 	
 	func refreshAll(for account: Account, completion: @escaping (Result<Void, Error>) -> Void) {
@@ -101,17 +98,15 @@ final class CloudKitAccountDelegate: AccountDelegate {
 	}
 	
 	func refreshArticleStatus(for account: Account, completion: @escaping ((Result<Void, Error>) -> Void)) {
-		os_log(.debug, log: log, "Refreshing article statuses...")
+		let op = CloudKitReceiveStatusOperation(articlesZone: articlesZone)
-		
+		op.completionBlock = { mainThreadOperaion in
- 		articlesZone.refreshArticles() { result in
+			if mainThreadOperaion.isCanceled {
-			os_log(.debug, log: self.log, "Done refreshing article statuses.")
+				completion(.failure(CloudKitAccountDelegateError.unknown))
-			switch result {
+			} else {
-			case .success:
 				completion(.success(()))
-			case .failure(let error):
-				completion(.failure(error))
 			}
 		}
+		mainThreadOperationQueue.add(op)
 	}
 	
 	func importOPML(for account:Account, opmlFile: URL, completion: @escaping (Result<Void, Error>) -> Void) {
@@ -420,17 +415,15 @@ final class CloudKitAccountDelegate: AccountDelegate {
 					os_log(.error, log: self.log, "Error adding account container: %@", error.localizedDescription)
 				}
 			}
-			zones.forEach { zone in
+			accountZone.subscribeToZoneChanges()
-				zone.subscribeToZoneChanges()
+			articlesZone.subscribeToZoneChanges()
-			}
 		}
 		
 	}
 	
 	func accountWillBeDeleted(_ account: Account) {
-		zones.forEach { zone in
+		accountZone.resetChangeToken()
-			zone.resetChangeToken()
+		articlesZone.resetChangeToken()
-		}
 	}
 
 	static func validateCredentials(transport: Transport, credentials: Credentials, endpoint: URL? = nil, completion: (Result<Credentials?, Error>) -> Void) {
@@ -770,94 +763,19 @@ private extension CloudKitAccountDelegate {
 	}
 
 	func sendArticleStatus(for account: Account, showProgress: Bool, completion: @escaping ((Result<Void, Error>) -> Void)) {
-		os_log(.debug, log: log, "Sending article statuses...")
+		let op = CloudKitSendStatusOperation(account: account,
-
+											 articlesZone: articlesZone,
-		database.selectForProcessing { result in
+											 refreshProgress: refreshProgress,
-
+											 showProgress: showProgress,
-			func processStatuses(_ syncStatuses: [SyncStatus]) {
+											 database: database)
-				guard syncStatuses.count > 0 else {
+		op.completionBlock = { mainThreadOperaion in
-					os_log(.debug, log: self.log, "Done sending article statuses.")
+			if mainThreadOperaion.isCanceled {
-					completion(.success(()))
+				completion(.failure(CloudKitAccountDelegateError.unknown))
-					return
+			} else {
-				}
-
-				let group = DispatchGroup()
-				let syncStatusChunks = syncStatuses.chunked(into: 300)
-				
-				if showProgress {
-					self.refreshProgress.addToNumberOfTasksAndRemaining(syncStatusChunks.count)
-				}
-				
-				for syncStatusChunk in syncStatusChunks {
-					group.enter()
-					self.sendArticleStatusChunk(for: account, syncStatuses: syncStatusChunk, showProgress: showProgress) {
-						group.leave()
-					}
-				}
-				
-				group.notify(queue: DispatchQueue.main) {
-					os_log(.debug, log: self.log, "Done sending article statuses.")
 				completion(.success(()))
 			}
-				
-			}
-
-			switch result {
-			case .success(let syncStatuses):
-				processStatuses(syncStatuses)
-			case .failure(let databaseError):
-				completion(.failure(databaseError))
-			}
-		}
-	}
-	
-	func sendArticleStatusChunk(for account: Account, syncStatuses: [SyncStatus], showProgress: Bool, completion: @escaping () -> Void) {
-		
-		let articleIDs = syncStatuses.map({ $0.articleID })
-		account.fetchArticlesAsync(.articleIDs(Set(articleIDs))) { result in
-			
-			func processWithArticles(_ articles: Set<Article>) {
-				
-				let syncStatusesDict = Dictionary(grouping: syncStatuses, by: { $0.articleID })
-				let articlesDict = articles.reduce(into: [String: Article]()) { result, article in
-					result[article.articleID] = article
-				}
-				let statusUpdates = syncStatusesDict.map { (key, value) in
-					return CloudKitArticleStatusUpdate(articleID: key, statuses: value, article: articlesDict[key])
-				}
-				
-				self.articlesZone.modifyArticles(statusUpdates) { result in
-					switch result {
-					case .success:
-						self.database.deleteSelectedForProcessing(syncStatuses.map({ $0.articleID })) { _ in
-							if showProgress {
-								self.refreshProgress.completeTask()
-							}
-							os_log(.debug, log: self.log, "Done sending article status block...")
-							completion()
-						}
-					case .failure(let error):
-						self.database.resetSelectedForProcessing(syncStatuses.map({ $0.articleID })) { _ in
-							self.processAccountError(account, error)
-							os_log(.error, log: self.log, "Send article status modify articles error: %@.", error.localizedDescription)
-							completion()
-						}
-					}
-				}
-				
-			}
-
-			switch result {
-			case .success(let articles):
-				processWithArticles(articles)
-			case .failure(let databaseError):
-				self.database.resetSelectedForProcessing(syncStatuses.map({ $0.articleID })) { _ in
-					os_log(.error, log: self.log, "Send article status fetch articles error: %@.", databaseError.localizedDescription)
-					completion()
-				}
-			}
-
 		}
+		mainThreadOperationQueue.add(op)
 	}
 	
 }
@@ -875,3 +793,4 @@ extension CloudKitAccountDelegate: LocalAccountRefresherDelegate {
 	}
 	
 }
+

Frameworks/Account/CloudKit/CloudKitReceiveStatusOperation.swift

@@ -0,0 +1,50 @@
+//
+//  CloudKitReceiveStatusOperation.swift
+//  Account
+//
+//  Created by Maurice Parker on 5/2/20.
+//  Copyright © 2020 Ranchero Software, LLC. All rights reserved.
+//
+
+import Foundation
+import os.log
+import RSCore
+
+class CloudKitReceiveStatusOperation: MainThreadOperation {
+	
+	private var log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "CloudKit")
+
+	// MainThreadOperation
+	public var isCanceled = false
+	public var id: Int?
+	public weak var operationDelegate: MainThreadOperationDelegate?
+	public var name: String? = "CloudKitReceiveStatusOperation"
+	public var completionBlock: MainThreadOperation.MainThreadOperationCompletionBlock?
+
+	private weak var articlesZone: CloudKitArticlesZone?
+	
+	init(articlesZone: CloudKitArticlesZone) {
+		self.articlesZone = articlesZone
+	}
+	
+	func run() {
+		guard let articlesZone = articlesZone else {
+			self.operationDelegate?.operationDidComplete(self)
+			return
+		}
+		
+		os_log(.debug, log: log, "Refreshing article statuses...")
+		
+ 		articlesZone.refreshArticles() { result in
+			os_log(.debug, log: self.log, "Done refreshing article statuses.")
+			switch result {
+			case .success:
+				self.operationDelegate?.operationDidComplete(self)
+			case .failure(let error):
+				os_log(.error, log: self.log, "Receive status error: %@.", error.localizedDescription)
+				self.operationDelegate?.cancelOperation(self)
+			}
+		}
+	}
+	
+}

Frameworks/Account/CloudKit/CloudKitRemoteNotificationOperation.swift

@@ -0,0 +1,52 @@
+//
+//  CloudKitRemoteNotificationOperation.swift
+//  Account
+//
+//  Created by Maurice Parker on 5/2/20.
+//  Copyright © 2020 Ranchero Software, LLC. All rights reserved.
+//
+
+import Foundation
+
+import os.log
+import RSCore
+
+class CloudKitRemoteNotificationOperation: MainThreadOperation {
+	
+	private var log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "CloudKit")
+
+	// MainThreadOperation
+	public var isCanceled = false
+	public var id: Int?
+	public weak var operationDelegate: MainThreadOperationDelegate?
+	public var name: String? = "CloudKitRemoteNotificationOperation"
+	public var completionBlock: MainThreadOperation.MainThreadOperationCompletionBlock?
+
+	private weak var accountZone: CloudKitAccountZone?
+	private weak var articlesZone: CloudKitArticlesZone?
+	private var userInfo: [AnyHashable : Any]
+	
+	init(accountZone: CloudKitAccountZone, articlesZone: CloudKitArticlesZone, userInfo: [AnyHashable : Any]) {
+		self.accountZone = accountZone
+		self.articlesZone = articlesZone
+		self.userInfo = userInfo
+	}
+
+	func run() {
+		guard let accountZone = accountZone, let articlesZone = articlesZone else {
+			self.operationDelegate?.operationDidComplete(self)
+			return
+		}
+		
+		os_log(.debug, log: log, "Processing remote notification...")
+		
+		accountZone.receiveRemoteNotification(userInfo: userInfo) {
+			articlesZone.receiveRemoteNotification(userInfo: self.userInfo) {
+				os_log(.debug, log: self.log, "Done processing remote notification.")
+				self.operationDelegate?.operationDidComplete(self)
+			}
+		}
+		
+	}
+	
+}

Frameworks/Account/CloudKit/CloudKitSendStatusOperation.swift

@@ -0,0 +1,147 @@
+//
+//  CloudKitSendStatusOperation.swift
+//  Account
+//
+//  Created by Maurice Parker on 5/2/20.
+//  Copyright © 2020 Ranchero Software, LLC. All rights reserved.
+//
+
+import Foundation
+import Articles
+import os.log
+import RSCore
+import RSWeb
+import SyncDatabase
+
+class CloudKitSendStatusOperation: MainThreadOperation {
+	
+	private var log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "CloudKit")
+
+	// MainThreadOperation
+	public var isCanceled = false
+	public var id: Int?
+	public weak var operationDelegate: MainThreadOperationDelegate?
+	public var name: String? = "CloudKitSendStatusOperation"
+	public var completionBlock: MainThreadOperation.MainThreadOperationCompletionBlock?
+
+	private weak var account: Account?
+	private weak var articlesZone: CloudKitArticlesZone?
+	private weak var refreshProgress: DownloadProgress?
+	private var showProgress: Bool
+	private var database: SyncDatabase
+
+	init(account: Account, articlesZone: CloudKitArticlesZone, refreshProgress: DownloadProgress, showProgress: Bool, database: SyncDatabase) {
+		self.account = account
+		self.articlesZone = articlesZone
+		self.refreshProgress = refreshProgress
+		self.showProgress = showProgress
+		self.database = database
+	}
+	
+	func run() {
+		os_log(.debug, log: log, "Sending article statuses...")
+
+		database.selectForProcessing { result in
+
+			func processStatuses(_ syncStatuses: [SyncStatus]) {
+				guard syncStatuses.count > 0 else {
+					os_log(.debug, log: self.log, "Done sending article statuses.")
+					self.operationDelegate?.operationDidComplete(self)
+					return
+				}
+
+				let group = DispatchGroup()
+				let syncStatusChunks = syncStatuses.chunked(into: 300)
+				
+				if self.showProgress {
+					self.refreshProgress?.addToNumberOfTasksAndRemaining(syncStatusChunks.count)
+				}
+				
+				for syncStatusChunk in syncStatusChunks {
+					group.enter()
+					self.sendArticleStatusChunk(syncStatuses: syncStatusChunk) {
+						group.leave()
+					}
+				}
+				
+				group.notify(queue: DispatchQueue.main) {
+					os_log(.debug, log: self.log, "Done sending article statuses.")
+					self.operationDelegate?.operationDidComplete(self)
+				}
+				
+			}
+
+			switch result {
+			case .success(let syncStatuses):
+				processStatuses(syncStatuses)
+			case .failure(let databaseError):
+				os_log(.error, log: self.log, "Send status error: %@.", databaseError.localizedDescription)
+				self.operationDelegate?.cancelOperation(self)
+			}
+		}
+		
+	}
+	
+	func sendArticleStatusChunk(syncStatuses: [SyncStatus], completion: @escaping () -> Void) {
+		guard let account = account, let articlesZone = articlesZone else {
+			completion()
+			return
+		}
+		
+		let articleIDs = syncStatuses.map({ $0.articleID })
+		account.fetchArticlesAsync(.articleIDs(Set(articleIDs))) { result in
+			
+			func processWithArticles(_ articles: Set<Article>) {
+				
+				let syncStatusesDict = Dictionary(grouping: syncStatuses, by: { $0.articleID })
+				let articlesDict = articles.reduce(into: [String: Article]()) { result, article in
+					result[article.articleID] = article
+				}
+				let statusUpdates = syncStatusesDict.map { (key, value) in
+					return CloudKitArticleStatusUpdate(articleID: key, statuses: value, article: articlesDict[key])
+				}
+				
+				articlesZone.modifyArticles(statusUpdates) { result in
+					switch result {
+					case .success:
+						self.database.deleteSelectedForProcessing(syncStatuses.map({ $0.articleID })) { _ in
+							if self.showProgress {
+								self.refreshProgress?.completeTask()
+							}
+							os_log(.debug, log: self.log, "Done sending article status block...")
+							completion()
+						}
+					case .failure(let error):
+						self.database.resetSelectedForProcessing(syncStatuses.map({ $0.articleID })) { _ in
+							self.processAccountError(account, error)
+							os_log(.error, log: self.log, "Send article status modify articles error: %@.", error.localizedDescription)
+							completion()
+						}
+					}
+				}
+				
+			}
+
+			switch result {
+			case .success(let articles):
+				processWithArticles(articles)
+			case .failure(let databaseError):
+				self.database.resetSelectedForProcessing(syncStatuses.map({ $0.articleID })) { _ in
+					os_log(.error, log: self.log, "Send article status fetch articles error: %@.", databaseError.localizedDescription)
+					completion()
+				}
+			}
+
+		}
+	}
+	
+	func processAccountError(_ account: Account, _ error: Error) {
+		if case CloudKitZoneError.userDeletedZone = error {
+			account.removeFeeds(account.topLevelWebFeeds)
+			for folder in account.folders ?? Set<Folder>() {
+				account.removeFolder(folder)
+			}
+		}
+	}
+
+}

iOS/AppDelegate.swift

@@ -24,7 +24,6 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
 	private var syncBackgroundUpdateTask = UIBackgroundTaskIdentifier.invalid
 	
 	var syncTimer: ArticleStatusSyncTimer?
-	private let remoteNotificationOperationQueue = MainThreadOperationQueue()
 	
 	var shuttingDown = false {
 		didSet {
@@ -112,9 +111,14 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
 		
 	}
 	
-    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any], fetchCompletionHandler completion: @escaping (UIBackgroundFetchResult) -> Void) {
+    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
-		let op = RemoteNotificationOperation(userInfo: userInfo, completion: completion)
+		DispatchQueue.main.async {
-		remoteNotificationOperationQueue.add(op)
+			self.resumeDatabaseProcessingIfNecessary()
+			AccountManager.shared.receiveRemoteNotification(userInfo: userInfo) {
+				self.suspendApplication()
+				completionHandler(.newData)
+			}
+		}
     }
 	
 	func applicationWillTerminate(_ application: UIApplication) {
@@ -391,31 +395,3 @@ private extension AppDelegate {
 	}
 	
 }
-
-class RemoteNotificationOperation: MainThreadOperation {
-	
-	// MainThreadOperation
-	public var isCanceled = false
-	public var id: Int?
-	public weak var operationDelegate: MainThreadOperationDelegate?
-	public var name: String? = "RemoteNotificationOperation"
-	public var completionBlock: MainThreadOperation.MainThreadOperationCompletionBlock?
-
-	private var userInfo: [AnyHashable : Any]
-	private var completion: (UIBackgroundFetchResult) -> Void
-	
-	init(userInfo: [AnyHashable : Any], completion: @escaping (UIBackgroundFetchResult) -> Void) {
-		self.userInfo = userInfo
-		self.completion = completion
-	}
-	
-	func run() {
-		appDelegate.resumeDatabaseProcessingIfNecessary()
-		AccountManager.shared.receiveRemoteNotification(userInfo: userInfo) {
-			appDelegate.suspendApplication()
-			self.completion(.newData)
-			self.operationDelegate?.operationDidComplete(self)
-		}
-	}
-	
-}