Merge pull request #4 from Ranchero-Software/ios-release

PR

Frameworks/Account/AccountMetadata.swift

@@ -23,7 +23,6 @@ final class AccountMetadata: Codable {
 		case lastArticleFetchStartTime = "lastArticleFetch"
 		case lastArticleFetchEndTime
 		case endpointURL
-		case lastCredentialRenewTime = "lastCredentialRenewTime"
 		case performedApril2020RetentionPolicyChange
 	}
 
@@ -82,16 +81,6 @@ final class AccountMetadata: Codable {
 			}
 		}
 	}
-	
-	/// The last moment an account successfully renewed its credentials, or `nil` if no such moment exists.
-	/// An account delegate can use this value to decide when to next ask the service provider to renew credentials.
-	var lastCredentialRenewTime: Date? {
-		didSet {
-			if lastCredentialRenewTime != oldValue {
-				valueDidChange(.lastCredentialRenewTime)
-			}
-		}
-	}
 
 	var performedApril2020RetentionPolicyChange: Bool? {
 		didSet {

Frameworks/Account/Feedly/FeedlyAPICaller.swift

@@ -9,6 +9,12 @@
 import Foundation
 import RSWeb
 
+protocol FeedlyAPICallerDelegate: class {
+	/// Implemented by the `FeedlyAccountDelegate` reauthorize the client with a fresh OAuth token so the client can retry the unauthorized request.
+	/// Pass `true` to the completion handler if the failing request should be retried with a fresh token or `false` if the unauthorized request should complete with the original failure error.
+	func reauthorizeFeedlyAPICaller(_ caller: FeedlyAPICaller, completionHandler: @escaping (Bool) -> ())
+}
+
 final class FeedlyAPICaller {
 	
 	enum API {
@@ -47,6 +53,8 @@ final class FeedlyAPICaller {
 		self.baseUrlComponents = api.baseUrlComponents
 	}
 	
+	weak var delegate: FeedlyAPICallerDelegate?
+	
 	var credentials: Credentials?
 	
 	var server: String? {
@@ -69,6 +77,54 @@ final class FeedlyAPICaller {
 		isSuspended = false
 	}
 	
+	func send<R: Decodable>(request: URLRequest, resultType: R.Type, dateDecoding: JSONDecoder.DateDecodingStrategy = .iso8601, keyDecoding: JSONDecoder.KeyDecodingStrategy = .useDefaultKeys, completion: @escaping (Result<(HTTPURLResponse, R?), Error>) -> Void) {
+		transport.send(request: request, resultType: resultType, dateDecoding: dateDecoding, keyDecoding: keyDecoding) { [weak self] result in
+			assert(Thread.isMainThread)
+			
+			switch result {
+			case .success:
+				completion(result)
+			case .failure(let error):
+				switch error {
+				case TransportError.httpError(let statusCode) where statusCode == 401:
+					
+					assert(self == nil ? true : self?.delegate != nil, "Check the delegate is set to \(FeedlyAccountDelegate.self).")
+					
+					guard let self = self, let delegate = self.delegate else {
+						completion(result)
+						return
+					}
+					
+					/// Capture the credentials before the reauthorization to check for a change.
+					let credentialsBefore = self.credentials
+					
+					delegate.reauthorizeFeedlyAPICaller(self) { [weak self] isReauthorizedAndShouldRetry in
+						assert(Thread.isMainThread)
+						
+						guard isReauthorizedAndShouldRetry, let self = self else {
+							completion(result)
+							return
+						}
+						
+						// Check for a change. Not only would it help debugging, but it'll also catch an infinitely recursive attempt to refresh.
+						guard let accessToken = self.credentials?.secret, accessToken != credentialsBefore?.secret else {
+							assertionFailure("Could not update the request with a new OAuth token. Did \(String(describing: self.delegate)) set them on \(self)?")
+							completion(result)
+							return
+						}
+						
+						var reauthorizedRequest = request
+						reauthorizedRequest.setValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
+						
+						self.send(request: reauthorizedRequest, resultType: resultType, dateDecoding: dateDecoding, keyDecoding: keyDecoding, completion: completion)
+					}
+				default:
+					completion(result)
+				}
+			}
+		}
+	}
+	
 	func importOpml(_ opmlData: Data, completion: @escaping (Result<Void, Error>) -> ()) {
 		guard !isSuspended else {
 			return DispatchQueue.main.async {
@@ -95,7 +151,7 @@ final class FeedlyAPICaller {
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		request.httpBody = opmlData
 		
-		transport.send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (httpResponse, _)):
 				if httpResponse.statusCode == 200 {
@@ -147,7 +203,7 @@ final class FeedlyAPICaller {
 			}
 		}
 		
-		transport.send(request: request, resultType: [FeedlyCollection].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: [FeedlyCollection].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (httpResponse, collections)):
 				if httpResponse.statusCode == 200, let collection = collections?.first {
@@ -200,7 +256,7 @@ final class FeedlyAPICaller {
 			}
 		}
 		
-		transport.send(request: request, resultType: [FeedlyCollection].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: [FeedlyCollection].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (httpResponse, collections)):
 				if httpResponse.statusCode == 200, let collection = collections?.first {
@@ -248,7 +304,7 @@ final class FeedlyAPICaller {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (httpResponse, _)):
 				if httpResponse.statusCode == 200 {
@@ -281,14 +337,8 @@ final class FeedlyAPICaller {
 			}
 		}
 		
-		guard let encodedFeedId = encodeForURLPath(feedId) else {
-			return DispatchQueue.main.async {
-				completion(.failure(FeedlyAccountDelegateError.unexpectedResourceId(feedId)))
-			}
-		}
-		
 		var components = baseUrlComponents
-		components.percentEncodedPath = "/v3/collections/\(encodedCollectionId)/feeds/\(encodedFeedId)"
+		components.percentEncodedPath = "/v3/collections/\(encodedCollectionId)/feeds/.mdelete"
 		
 		guard let url = components.url else {
 			fatalError("\(components) does not produce a valid URL.")
@@ -300,7 +350,20 @@ final class FeedlyAPICaller {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: [FeedlyFeed].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		do {
+			struct RemovableFeed: Encodable {
+				let id: String
+			}
+			let encoder = JSONEncoder()
+			let data = try encoder.encode([RemovableFeed(id: feedId)])
+			request.httpBody = data
+		} catch {
+			return DispatchQueue.main.async {
+				completion(.failure(error))
+			}
+		}
+		
+		send(request: request, resultType: [FeedlyFeed].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success((let httpResponse, _)):
 				if httpResponse.statusCode == 200 {
@@ -362,7 +425,7 @@ extension FeedlyAPICaller: FeedlyAddFeedToCollectionService {
 			}
 		}
 		
-		transport.send(request: request, resultType: [FeedlyFeed].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: [FeedlyFeed].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success((_, let collectionFeeds)):
 				if let feeds = collectionFeeds {
@@ -428,7 +491,7 @@ extension FeedlyAPICaller: OAuthAuthorizationCodeGrantRequesting {
 			return
 		}
 		
-		transport.send(request: request, resultType: AccessTokenResponse.self, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: AccessTokenResponse.self, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, tokenResponse)):
 				if let response = tokenResponse {
@@ -475,7 +538,7 @@ extension FeedlyAPICaller: OAuthAcessTokenRefreshRequesting {
 			return
 		}
 		
-		transport.send(request: request, resultType: AccessTokenResponse.self, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: AccessTokenResponse.self, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, tokenResponse)):
 				if let response = tokenResponse {
@@ -516,7 +579,7 @@ extension FeedlyAPICaller: FeedlyGetCollectionsService {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: [FeedlyCollection].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: [FeedlyCollection].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, collections)):
 				if let response = collections {
@@ -584,7 +647,7 @@ extension FeedlyAPICaller: FeedlyGetStreamContentsService {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: FeedlyStream.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: FeedlyStream.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, collections)):
 				if let response = collections {
@@ -652,7 +715,7 @@ extension FeedlyAPICaller: FeedlyGetStreamIdsService {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: FeedlyStreamIds.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: FeedlyStreamIds.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, collections)):
 				if let response = collections {
@@ -707,7 +770,7 @@ extension FeedlyAPICaller: FeedlyGetEntriesService {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: [FeedlyEntry].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: [FeedlyEntry].self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, entries)):
 				if let response = entries {
@@ -766,7 +829,7 @@ extension FeedlyAPICaller: FeedlyMarkArticlesService {
 			}
 		}
 		
-		transport.send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (httpResponse, _)):
 				if httpResponse.statusCode == 200 {
@@ -810,7 +873,7 @@ extension FeedlyAPICaller: FeedlySearchService {
 		request.addValue("application/json", forHTTPHeaderField: HTTPRequestHeader.contentType)
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		
-		transport.send(request: request, resultType: FeedlyFeedsSearchResponse.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: FeedlyFeedsSearchResponse.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (_, searchResponse)):
 				if let response = searchResponse {
@@ -852,7 +915,7 @@ extension FeedlyAPICaller: FeedlyLogoutService {
 		request.addValue("application/json", forHTTPHeaderField: "Accept-Type")
 		request.addValue("OAuth \(accessToken)", forHTTPHeaderField: HTTPRequestHeader.authorization)
 		
-		transport.send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
+		send(request: request, resultType: String.self, dateDecoding: .millisecondsSince1970, keyDecoding: .convertFromSnakeCase) { result in
 			switch result {
 			case .success(let (httpResponse, _)):
 				if httpResponse.statusCode == 200 {

Frameworks/Account/Feedly/FeedlyAccountDelegate.swift

@@ -37,12 +37,14 @@ final class FeedlyAccountDelegate: AccountDelegate {
 	
 	var credentials: Credentials? {
 		didSet {
+			#if DEBUG
 			// https://developer.feedly.com/v3/developer/
 			if let devToken = ProcessInfo.processInfo.environment["FEEDLY_DEV_ACCESS_TOKEN"], !devToken.isEmpty {
 				caller.credentials = Credentials(type: .oauthAccessToken, username: "Developer", secret: devToken)
-			} else {
+				return
-				caller.credentials = credentials
 			}
+			#endif
+			 caller.credentials = credentials
 		}
 	}
 	
@@ -52,6 +54,10 @@ final class FeedlyAccountDelegate: AccountDelegate {
 	
 	var refreshProgress = DownloadProgress(numberOfTasks: 0)
 	
+	/// Set on `accountDidInitialize` for the purposes of refreshing OAuth tokens when they expire.
+	/// See the implementation for `FeedlyAPICallerDelegate`.
+	private weak var initializedAccount: Account?
+	
 	internal let caller: FeedlyAPICaller
 	
 	private let log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "Feedly")
@@ -91,6 +97,8 @@ final class FeedlyAccountDelegate: AccountDelegate {
 		let databaseFilePath = (dataFolder as NSString).appendingPathComponent("Sync.sqlite3")
 		self.database = SyncDatabase(databaseFilePath: databaseFilePath)
 		self.oauthAuthorizationClient = api.oauthAuthorizationClient
+		
+		self.caller.delegate = self
 	}
 	
 	// MARK: Account API
@@ -112,17 +120,10 @@ final class FeedlyAccountDelegate: AccountDelegate {
 		
 		let log = self.log
 		
-		let refreshAccessToken = FeedlyRefreshAccessTokenOperation(account: account, service: self, oauthClient: oauthAuthorizationClient, refreshDate: Date(), log: log)
-		refreshAccessToken.downloadProgress = refreshProgress
-		operationQueue.add(refreshAccessToken)
-		
 		let syncAllOperation = FeedlySyncAllOperation(account: account, feedlyUserId: credentials.username, caller: caller, database: database, lastSuccessfulFetchStartDate: accountMetadata?.lastArticleFetchStartTime, downloadProgress: refreshProgress, log: log)
 		
 		syncAllOperation.downloadProgress = refreshProgress
 		
-		// Ensure the sync uses the latest credential.
-		syncAllOperation.addDependency(refreshAccessToken)
-		
 		let date = Date()
 		syncAllOperation.syncCompletionHandler = { [weak self] result in
 			if case .success = result {
@@ -500,6 +501,7 @@ final class FeedlyAccountDelegate: AccountDelegate {
 	}
 	
 	func accountDidInitialize(_ account: Account) {
+		initializedAccount = account
 		credentials = try? account.retrieveCredentials(type: .oauthAccessToken)
 	}
 	
@@ -533,3 +535,37 @@ final class FeedlyAccountDelegate: AccountDelegate {
 		caller.resume()
 	}
 }
+
+extension FeedlyAccountDelegate: FeedlyAPICallerDelegate {
+	
+	func reauthorizeFeedlyAPICaller(_ caller: FeedlyAPICaller, completionHandler: @escaping (Bool) -> ()) {
+		guard let account = initializedAccount else {
+			completionHandler(false)
+			return
+		}
+		
+		/// Captures a failure to refresh a token, assuming that it was refreshed unless told otherwise.
+		final class RefreshAccessTokenOperationDelegate: FeedlyOperationDelegate {
+			
+			private(set) var didReauthorize = true
+			
+			func feedlyOperation(_ operation: FeedlyOperation, didFailWith error: Error) {
+				didReauthorize = false
+			}
+		}
+		
+		let refreshAccessToken = FeedlyRefreshAccessTokenOperation(account: account, service: self, oauthClient: oauthAuthorizationClient, log: log)
+		refreshAccessToken.downloadProgress = refreshProgress
+		
+		/// This must be strongly referenced by the completionBlock of the `FeedlyRefreshAccessTokenOperation`.
+		let refreshAccessTokenDelegate = RefreshAccessTokenOperationDelegate()
+		refreshAccessToken.delegate = refreshAccessTokenDelegate
+		
+		refreshAccessToken.completionBlock = { operation in
+			assert(Thread.isMainThread)
+			completionHandler(refreshAccessTokenDelegate.didReauthorize && !operation.isCanceled)
+		}
+		
+		MainThreadOperationQueue.shared.add(refreshAccessToken)
+	}
+}

Frameworks/Account/Feedly/OAuthAuthorizationClient+Feedly.swift

@@ -25,11 +25,11 @@ extension OAuthAuthorizationClient {
 		/// See https://developer.feedly.com/v3/sandbox/ for more information.
 		/// The return value models public sandbox API values found at:
 		/// https://groups.google.com/forum/#!topic/feedly-cloud/WwQWMgDmOuw
-		/// They are due to expire on January 31 2020.
+		/// They are due to expire on May 31st 2020.
 		/// Verify the sandbox URL host in the FeedlyAPICaller.API.baseUrlComponents method, too.
 		return OAuthAuthorizationClient(id: "sandbox",
 										redirectUri: "urn:ietf:wg:oauth:2.0:oob",
 										state: nil,
-										secret: "nZmS4bqxgRQkdPks")
+										secret: "4ZfZ5DvqmJ8vKgMj")
 	}
 }

Frameworks/Account/Feedly/Operations/FeedlyRefreshAccessTokenOperation.swift

@@ -17,32 +17,14 @@ final class FeedlyRefreshAccessTokenOperation: FeedlyOperation {
 	let account: Account
 	let log: OSLog
 	
-	/// The moment the refresh is being requested. The token will refresh only if the account's `lastCredentialRenewTime` is not on the same day as this moment. When nil, the operation will always refresh the token.
+	init(account: Account, service: OAuthAccessTokenRefreshing, oauthClient: OAuthAuthorizationClient, log: OSLog) {
-	let refreshDate: Date?
-	
-	init(account: Account, service: OAuthAccessTokenRefreshing, oauthClient: OAuthAuthorizationClient, refreshDate: Date?, log: OSLog) {
 		self.oauthClient = oauthClient
 		self.service = service
 		self.account = account
-		self.refreshDate = refreshDate
 		self.log = log
 	}
 	
 	override func run() {
-		// Only refresh the token if these dates are not on the same day.
-		let shouldRefresh: Bool = {
-			guard let date = refreshDate, let lastRenewDate = account.metadata.lastCredentialRenewTime else {
-				return true
-			}
-			return !Calendar.current.isDate(lastRenewDate, equalTo: date, toGranularity: .day)
-		}()
-		
-		guard shouldRefresh else {
-			os_log(.debug, log: log, "Skipping access token renewal.")
-			didFinish()
-			return
-		}
-		
 		let refreshToken: Credentials
 		
 		do {
@@ -82,8 +64,6 @@ final class FeedlyRefreshAccessTokenOperation: FeedlyOperation {
 				// Now store the access token because we want the account delegate to use it.
 				try account.storeCredentials(grant.accessToken)
 				
-				account.metadata.lastCredentialRenewTime = Date()
-				
 				didFinish()
 			} catch {
 				didFinish(with: error)

iOS/AppDelegate.swift

@@ -90,9 +90,9 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
 		DispatchQueue.main.async {
 			self.unreadCount = AccountManager.shared.unreadCount
 		}
-		
+				
-		UNUserNotificationCenter.current().requestAuthorization(options:[.badge, .sound, .alert]) { (granted, error) in
+		UNUserNotificationCenter.current().getNotificationSettings { (settings) in
-			if granted {
+			if settings.authorizationStatus == .authorized {
 				DispatchQueue.main.async {
 					UIApplication.shared.registerForRemoteNotifications()
 				}

iOS/Inspector/WebFeedInspectorViewController.swift

@@ -9,6 +9,7 @@
 import UIKit
 import Account
 import SafariServices
+import UserNotifications
 
 class WebFeedInspectorViewController: UITableViewController {
 	
@@ -38,6 +39,8 @@ class WebFeedInspectorViewController: UITableViewController {
 		return webFeed.homePageURL == nil
 	}
 	
+	private var userNotificationSettings: UNNotificationSettings?
+	
 	override func viewDidLoad() {
 		tableView.register(InspectorIconHeaderView.self, forHeaderFooterViewReuseIdentifier: "SectionHeader")
 		
@@ -51,6 +54,13 @@ class WebFeedInspectorViewController: UITableViewController {
 		feedURLLabel.text = webFeed.url
 		
 		NotificationCenter.default.addObserver(self, selector: #selector(webFeedIconDidBecomeAvailable(_:)), name: .WebFeedIconDidBecomeAvailable, object: nil)
+		
+		NotificationCenter.default.addObserver(self, selector: #selector(updateNotificationSettings), name: UIApplication.willEnterForegroundNotification, object: nil)
+		
+	}
+	
+	override func viewDidAppear(_ animated: Bool) {
+		updateNotificationSettings()
 	}
 	
 	override func viewDidDisappear(_ animated: Bool) {
@@ -67,7 +77,30 @@ class WebFeedInspectorViewController: UITableViewController {
 	}
 	
 	@IBAction func notifyAboutNewArticlesChanged(_ sender: Any) {
-		webFeed.isNotifyAboutNewArticles = notifyAboutNewArticlesSwitch.isOn
+		guard let settings = userNotificationSettings else {
+			notifyAboutNewArticlesSwitch.isOn = !notifyAboutNewArticlesSwitch.isOn
+			return
+		}
+		if settings.authorizationStatus == .denied {
+			notifyAboutNewArticlesSwitch.isOn = !notifyAboutNewArticlesSwitch.isOn
+			present(notificationUpdateErrorAlert(), animated: true, completion: nil)
+		} else if settings.authorizationStatus == .authorized {
+			webFeed.isNotifyAboutNewArticles = notifyAboutNewArticlesSwitch.isOn
+		} else {
+			UNUserNotificationCenter.current().requestAuthorization(options:[.badge, .sound, .alert]) { (granted, error) in
+				self.updateNotificationSettings()
+				if granted {
+					DispatchQueue.main.async {
+						self.webFeed.isNotifyAboutNewArticles = self.notifyAboutNewArticlesSwitch.isOn
+						UIApplication.shared.registerForRemoteNotifications()
+					}
+				} else {
+					DispatchQueue.main.async {
+						self.notifyAboutNewArticlesSwitch.isOn = !self.notifyAboutNewArticlesSwitch.isOn
+					}
+				}
+			}
+		}
 	}
 	
 	@IBAction func alwaysShowReaderViewChanged(_ sender: Any) {
@@ -158,3 +191,33 @@ extension WebFeedInspectorViewController: UITextFieldDelegate {
 	}
 	
 }
+
+// MARK: UNUserNotificationCenter
+
+extension WebFeedInspectorViewController {
+	
+	@objc
+	func updateNotificationSettings() {
+		UNUserNotificationCenter.current().getNotificationSettings { (settings) in
+			DispatchQueue.main.async {
+				self.userNotificationSettings = settings
+				if settings.authorizationStatus == .authorized {
+					UIApplication.shared.registerForRemoteNotifications()
+				}
+			}
+		}
+	}
+	
+	func notificationUpdateErrorAlert() -> UIAlertController {
+		let alert = UIAlertController(title: NSLocalizedString("Enable Notifications", comment: "Notifications"),
+									  message: NSLocalizedString("Notifications need to be enabled in the Settings app.", comment: "Notifications need to be enabled in the Settings app."), preferredStyle: .alert)
+		let openSettings = UIAlertAction(title: NSLocalizedString("Open Settings", comment: "Open Settings"), style: .default) { (action) in
+			UIApplication.shared.open(URL(string: UIApplication.openSettingsURLString)!, options: [UIApplication.OpenExternalURLOptionsKey.universalLinksOnly : false], completionHandler: nil)
+		}
+		let dismiss = UIAlertAction(title: NSLocalizedString("Dismiss", comment: "Dismiss"), style: .cancel, handler: nil)
+		alert.addAction(openSettings)
+		alert.addAction(dismiss)
+		return alert
+	}
+	
+}