Reconnect tunnel after migration from AppDelegate

3 files changed, 120 insertions, 94 deletions

diff --git a/ios/MullvadVPN/AppDelegate.swift b/ios/MullvadVPN/AppDelegate.swift
index dfdee88d7e..f4307d0f28 100644
--- a/ios/MullvadVPN/AppDelegate.swift
+++ b/ios/MullvadVPN/AppDelegate.swift
@@ -113,61 +113,7 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
         setupNotificationHandler()
         addApplicationNotifications(application: application)
 
-        let loadTunnelsOperation = AsyncBlockOperation(dispatchQueue: .main) { operation in
-            self.tunnelStore.loadPersistentTunnels { error in
-                if let error = error {
-                    self.logger.error(
-                        error: error,
-                        message: "Failed to load persistent tunnels."
-                    )
-                }
-                operation.finish()
-            }
-        }
-
-        let migrateSettingsOperation = AsyncBlockOperation(dispatchQueue: .main) { operation in
-            SettingsManager.migrateStore(with: self.proxyFactory) { error in
-                guard let error = error else {
-                    operation.finish()
-                    return
-                }
-
-                guard let migrationUIHandler = application.connectedScenes.compactMap({ scene in
-                    return scene.delegate as? SettingsMigrationUIHandler
-                }).first else {
-                    operation.finish()
-                    return
-                }
-
-                migrationUIHandler.showMigrationError(error) {
-                    operation.finish()
-                }
-            }
-        }
-        migrateSettingsOperation.addDependency(loadTunnelsOperation)
-
-        let loadTunnelConfigurationOperation =
-            AsyncBlockOperation(dispatchQueue: .main) { operation in
-                self.tunnelManager.loadConfiguration { error in
-                    // TODO: avoid throwing fatal error and show the problem report UI instead.
-                    if let error = error {
-                        fatalError(error.localizedDescription)
-                    }
-
-                    self.logger.debug("Finished initialization.")
-
-                    NotificationManager.shared.updateNotifications()
-                    self.storePaymentManager.startPaymentQueueMonitoring()
-
-                    operation.finish()
-                }
-            }
-        loadTunnelConfigurationOperation.addDependency(migrateSettingsOperation)
-
-        operationQueue.addOperations(
-            [loadTunnelsOperation, migrateSettingsOperation, loadTunnelConfigurationOperation],
-            waitUntilFinished: false
-        )
+        startInitialization(application: application)
 
         return true
     }
@@ -405,6 +351,81 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
         UNUserNotificationCenter.current().delegate = self
     }
 
+    private func startInitialization(application: UIApplication) {
+        let loadTunnelStoreOperation = AsyncBlockOperation(dispatchQueue: .main) { operation in
+            self.tunnelStore.loadPersistentTunnels { error in
+                if let error = error {
+                    self.logger.error(
+                        error: error,
+                        message: "Failed to load persistent tunnels."
+                    )
+                }
+                operation.finish()
+            }
+        }
+
+        let migrateSettingsOperation = ResultBlockOperation<SettingsMigrationResult, Error>(
+            dispatchQueue: .main
+        ) { operation in
+            SettingsManager.migrateStore(with: self.proxyFactory) { migrationResult in
+                let finishHandler = {
+                    operation.finish(completion: .success(migrationResult))
+                }
+
+                guard case let .failure(error) = migrationResult,
+                      let migrationUIHandler = application.connectedScenes.compactMap({ scene in
+                          return scene.delegate as? SettingsMigrationUIHandler
+                      }).first
+                else {
+                    finishHandler()
+                    return
+                }
+
+                migrationUIHandler.showMigrationError(error, completionHandler: finishHandler)
+            }
+        }
+        migrateSettingsOperation.addDependency(loadTunnelStoreOperation)
+
+        let initTunnelManagerOperation = AsyncBlockOperation(dispatchQueue: .main) { operation in
+            self.tunnelManager.loadConfiguration { error in
+                // TODO: avoid throwing fatal error and show the problem report UI instead.
+                if let error = error {
+                    fatalError(error.localizedDescription)
+                }
+
+                self.logger.debug("Finished initialization.")
+
+                NotificationManager.shared.updateNotifications()
+                self.storePaymentManager.startPaymentQueueMonitoring()
+
+                operation.finish()
+            }
+        }
+        initTunnelManagerOperation.addDependency(migrateSettingsOperation)
+
+        let reconnectTunnelOperation = TransformOperation<SettingsMigrationResult, Void, Error>(
+            dispatchQueue: .main
+        ) { migrationResult in
+            if case .success = migrationResult {
+                self.logger.debug("Reconnect the tunnel after settings migration.")
+
+                self.tunnelManager.reconnectTunnel(selectNewRelay: true)
+            }
+        }
+        reconnectTunnelOperation.inject(from: migrateSettingsOperation)
+        reconnectTunnelOperation.addDependency(initTunnelManagerOperation)
+
+        operationQueue.addOperations(
+            [
+                loadTunnelStoreOperation,
+                migrateSettingsOperation,
+                initTunnelManagerOperation,
+                reconnectTunnelOperation,
+            ],
+            waitUntilFinished: false
+        )
+    }
+
     // MARK: - StorePaymentManagerDelegate
 
     func storePaymentManager(
diff --git a/ios/MullvadVPN/SettingsManager/SettingsManager.swift b/ios/MullvadVPN/SettingsManager/SettingsManager.swift
index 2940937ae4..06ae10f1a6 100644
--- a/ios/MullvadVPN/SettingsManager/SettingsManager.swift
+++ b/ios/MullvadVPN/SettingsManager/SettingsManager.swift
@@ -15,6 +15,17 @@ private let keychainServiceName = "Mullvad VPN"
 private let accountTokenKey = "accountToken"
 private let accountExpiryKey = "accountExpiry"
 
+enum SettingsMigrationResult {
+    /// Nothing to migrate.
+    case nothing
+
+    /// Successfully performed migration.
+    case success
+
+    /// Failure when migrating store.
+    case failure(Error)
+}
+
 enum SettingsManager {
     private static let logger = Logger(label: "SettingsManager")
 
@@ -110,31 +121,35 @@ enum SettingsManager {
 
     /// Migrate settings store if needed.
     ///
-    /// The error returned in `completion` handler is set to `nil` upon success or when no
-    /// migration is not needed.
-    ///
     /// The following types of error are expected to be returned by this method:
     /// `SettingsMigrationError`, `UnsupportedSettingsVersionError`, `ReadSettingsVersionError`.
     static func migrateStore(
         with restFactory: REST.ProxyFactory,
-        completion: @escaping (Error?) -> Void
+        completion: @escaping (SettingsMigrationResult) -> Void
     ) {
-        let handleCompletion = { (error: Error?) in
+        let handleCompletion = { (result: SettingsMigrationResult) in
             // Reset store upon failure to migrate settings.
-            if error != nil {
+            if case .failure = result {
                 self.resetStore()
             }
-            completion(error)
+            completion(result)
         }
 
         if let legacySettings = readLegacySettings() {
             migrateLegacySettings(
                 restFactory: restFactory,
-                legacySettings: legacySettings,
-                completion: handleCompletion
-            )
+                legacySettings: legacySettings
+            ) { error in
+                handleCompletion(error.map { .failure($0) } ?? .success)
+            }
         } else {
-            migrateModernSettings(completion: handleCompletion)
+            do {
+                try checkLatestSettingsVersion()
+
+                handleCompletion(.nothing)
+            } catch {
+                handleCompletion(.failure(error))
+            }
         }
     }
 
@@ -171,29 +186,30 @@ enum SettingsManager {
         }
     }
 
-    private static func migrateModernSettings(completion: @escaping (Error?) -> Void) {
+    private static func checkLatestSettingsVersion() throws {
+        let settingsVersion: Int
         do {
             let parser = makeParser()
             let settingsData = try store.read(key: .settings)
-            let settingsVersion = try parser.parseVersion(data: settingsData)
-
-            if settingsVersion != SchemaVersion.current.rawValue {
-                let error = UnsupportedSettingsVersionError(
-                    storedVersion: settingsVersion,
-                    currentVersion: SchemaVersion.current
-                )
-
-                logger.error(error: error, message: "Encountered an unknown version.")
-
-                completion(error)
-            } else {
-                completion(nil)
-            }
+            settingsVersion = try parser.parseVersion(data: settingsData)
         } catch .itemNotFound as KeychainError {
-            completion(nil)
+            return
         } catch {
-            completion(ReadSettingsVersionError(underlyingError: error))
+            throw ReadSettingsVersionError(underlyingError: error)
         }
+
+        guard settingsVersion != SchemaVersion.current.rawValue else {
+            return
+        }
+
+        let error = UnsupportedSettingsVersionError(
+            storedVersion: settingsVersion,
+            currentVersion: SchemaVersion.current
+        )
+
+        logger.error(error: error, message: "Encountered an unknown version.")
+
+        throw error
     }
 
     /// Removes all legacy settings, device state and tunnel settings but keeps the last used
diff --git a/ios/MullvadVPN/TunnelManager/TunnelManager.swift b/ios/MullvadVPN/TunnelManager/TunnelManager.swift
index c117dee394..3854f3ca54 100644
--- a/ios/MullvadVPN/TunnelManager/TunnelManager.swift
+++ b/ios/MullvadVPN/TunnelManager/TunnelManager.swift
@@ -84,9 +84,6 @@ final class TunnelManager: StorePaymentObserver {
     /// Last processed device check identifier.
     private var lastDeviceCheckIdentifier: UUID?
 
-    /// Flag indicating tunnel reconnected after settings migration.
-    private var reconnectedTunnelAfterMigration = false
-
     // MARK: - Initialization
 
     init(
@@ -697,14 +694,6 @@ final class TunnelManager: StorePaymentObserver {
             // while the tunnel process is trying to connect.
             startPollingTunnelStatus(interval: establishingTunnelStatusPollInterval)
 
-            if newTunnelStatus.packetTunnelStatus.lastErrors.contains(.readConfiguration),
-               !reconnectedTunnelAfterMigration
-            {
-                reconnectTunnel(selectNewRelay: true)
-
-                reconnectedTunnelAfterMigration = true
-            }
-
         case .connected, .waitingForConnectivity:
             // Start polling tunnel status to keep connectivity status up to date.
             startPollingTunnelStatus(interval: establishedTunnelStatusPollInterval)