implement sync timeout

Shared/Common/Resources/BaseConstants.swift

@@ -10,6 +10,7 @@ public let isRunningTest = NSClassFromString("XCTestCase") != nil
 class Constant {
     class app {
         static let group = "group.org.mozilla.ios.Lockbox"
+        static let syncTimeout: Double = 20
     }
 
     struct fxa {
@@ -72,6 +73,7 @@ class Constant {
         static let usernamePlaceholder = NSLocalizedString("username_placeholder", value: "(no username)", comment: "Placeholder text when there is no username. String should include appropriate open/close parenthetical or similar symbols to indicate this is a placeholder, not a real username.")
         static let searchYourEntries = NSLocalizedString("search.placeholder", value: "Search logins", comment: "Placeholder text for search field")
         static let emptyListPlaceholder = NSLocalizedString("list.empty", value: "%@ lets you access passwords you’ve already saved to Firefox. To view your logins here, you’ll need to sign in and sync with Firefox.", comment: "Label shown when there are no logins to list. %@ will be replaced with the application name")
+        static let syncTimedOut = NSLocalizedString("sync.timeout", value: "Sync timed out", comment: "This is the message displayed when syncing entries from the server times out")
     }
 }
 

Shared/Store/BaseDataStore.swift

@@ -24,14 +24,16 @@ enum SyncError: Error {
 }
 
 enum SyncState: Equatable {
-    case Syncing, Synced
+    case Syncing, Synced, TimedOut
 
     public static func ==(lhs: SyncState, rhs: SyncState) -> Bool {
         switch (lhs, rhs) {
         case (Syncing, Syncing):
             return true
         case (Synced, Synced):
             return true
+        case (TimedOut, TimedOut):
+            return true
         default:
             return false
         }
@@ -71,7 +73,7 @@ class BaseDataStore {
 
     internal var disposeBag = DisposeBag()
     private var listSubject = BehaviorRelay<[LoginRecord]>(value: [])
-    private var syncSubject = ReplaySubject<SyncState>.create(bufferSize: 1)
+    private var syncSubject = BehaviorRelay<SyncState>(value: .Synced)
     private var storageStateSubject = ReplaySubject<LoginStoreState>.create(bufferSize: 1)
 
     private let dispatcher: Dispatcher
@@ -229,21 +231,29 @@ extension BaseDataStore {
             else { return }
 
         if (networkStore.isConnectedToNetwork) {
-            self.syncSubject.onNext(SyncState.Syncing)
+            self.syncSubject.accept(SyncState.Syncing)
         } else {
-            self.syncSubject.onNext(SyncState.Synced)
+            self.syncSubject.accept(SyncState.Synced)
             return
         }
-
+        
         queue.async {
+            self.queue.asyncAfter(deadline: .now() + Constant.app.syncTimeout, execute: {
+                // this block serves to "cancel" the sync if the operation is running slowly
+                if (self.syncSubject.value != .Synced) {
+                    self.syncSubject.accept(.TimedOut)
+                    self.dispatcher.dispatch(action: SentryAction(title: "Sync timeout without error", error: nil, function: "", line: ""))
+                }
+            })
+
             do {
                 try self.loginsStorage?.sync(unlockInfo: syncInfo)
             } catch let error as LoginStoreError {
                 self.storageStateSubject.onNext(.Errored(cause: error))
             } catch let error {
                 NSLog("Unknown error syncing: \(error)")
             }
-            self.syncSubject.onNext(SyncState.Synced)
+            self.syncSubject.accept(SyncState.Synced)
         }
     }
 

lockbox-ios/Action/SentryAction.swift

@@ -6,7 +6,7 @@ import Foundation
 
 struct SentryAction: Action {
     let title: String
-    let error: Error
+    let error: Error?
     let function: String
     let line: String
 }

lockbox-ios/Presenter/ItemListPresenter.swift

@@ -7,7 +7,7 @@ import RxSwift
 import RxCocoa
 import RxDataSources
 
-protocol ItemListViewProtocol: AlertControllerView, SpinnerAlertView, BaseItemListViewProtocol {
+protocol ItemListViewProtocol: AlertControllerView, StatusAlertView, SpinnerAlertView, BaseItemListViewProtocol {
     func bind(sortingButtonTitle: Driver<String>)
     func bind(scrollAction: Driver<ScrollAction>)
     var sortingButtonEnabled: AnyObserver<Bool>? { get }
@@ -174,7 +174,7 @@ extension ItemListPresenter {
     fileprivate func setupSpinnerDisplay() {
         // when this observable emits an event, the spinner gets dismissed
         let hideSpinnerObservable = self.dataStore.syncState
-                .filter { $0 == SyncState.Synced }
+                .filter { $0 == SyncState.Synced || $0 == SyncState.TimedOut }
                 .map { _ in return () }
                 .asDriver(onErrorJustReturn: ())
 
@@ -194,6 +194,15 @@ extension ItemListPresenter {
                     }
                 })
                 .disposed(by: self.disposeBag)
+
+        self.dataStore.syncState
+                .filter { $0 == SyncState.TimedOut }
+                .map { _ in () }
+                .asDriver(onErrorJustReturn: () )
+                .drive(onNext: { _ in
+                    self.view?.displayTemporaryAlert(Constant.string.syncTimedOut, timeout: 5)
+                })
+                .disposed(by: self.disposeBag)
     }
 }
 

lockbox-ios/Store/SentryStore.swift

@@ -18,7 +18,7 @@ class SentryStore {
                 .subscribe(onNext: { (action) in
                     Client.shared?.reportUserException(
                         action.title,
-                        reason: action.error.localizedDescription,
+                        reason: action.error?.localizedDescription ?? "",
                         language: NSLocale.preferredLanguages.first ?? "",
                         lineOfCode: action.line,
                         stackTrace: Thread.callStackSymbols,

lockbox-iosTests/BaseDataStoreSpec.swift

@@ -388,7 +388,7 @@ class BaseDataStoreSpec: QuickSpec {
                         let syncStates: [SyncState] = self.syncObserver.events.map {
                             $0.value.element!
                         }
-                        expect(syncStates).to(equal([SyncState.Synced, SyncState.Syncing, SyncState.Synced]))
+                        expect(syncStates).to(equal([SyncState.Synced, SyncState.Synced, SyncState.Syncing, SyncState.Synced]))
                     }
                 }
 

lockbox-iosTests/ItemListPresenterSpec.swift

@@ -31,10 +31,10 @@ class ItemListPresenterSpec: QuickSpec {
         var fakeOnSettingsPressed = PublishSubject<Void>()
         var fakeOnSortingButtonPressed = PublishSubject<Void>()
         var setFilterEnabledValue: Bool?
-
         var displayOptionSheetButtons: [AlertActionButtonConfiguration]?
-        var displayOptionSheetTitle: String?
+        var temporaryAlertArgument: String?
 
+        var displayOptionSheetTitle: String?
         func bind(items: Driver<[ItemSectionModel]>) {
             items.drive(itemsObserver).disposed(by: self.disposeBag)
         }
@@ -53,6 +53,10 @@ class ItemListPresenterSpec: QuickSpec {
             self.displayOptionSheetTitle = title
         }
 
+        func displayTemporaryAlert(_ message: String, timeout: TimeInterval) {
+            self.temporaryAlertArgument = message
+        }
+
         func dismissKeyboard() {
             self.dismissKeyboardCalled = true
         }
@@ -284,6 +288,16 @@ class ItemListPresenterSpec: QuickSpec {
                                 }
                             }
                         }
+
+                        describe("if the sync times out") {
+                            beforeEach {
+                                self.dataStore.syncStateStub.onNext(SyncState.TimedOut)
+                            }
+
+                            it("displays a temporary alert for the user") {
+                                expect(self.view.temporaryAlertArgument).to(equal(Constant.string.syncTimedOut))
+                            }
+                        }
                     }
 
                     describe("manual sync") {