Simplify persistence manager protocol

openHPI · Nov 27, 2018 · 6f78f9d · 6f78f9d
1 parent 277c367
commit 6f78f9d
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Showing 8 changed files with 62 additions and 97 deletions.
diff --git a/iOS/Base.lproj/Localizable.strings b/iOS/Base.lproj/Localizable.strings
@@ -1,4 +1,13 @@
 
+/* title of alert for stream download errors */
+"alert.download-error.documents.title" = "Error while downloading document";
+
+/* title of alert for slides download errors */
+"alert.download-error.slides.title" = "Error while downloading slides";
+
+/* title of alert for stream download errors */
+"alert.download-error.stream.title" = "Error while downloading video";
+
 /* alert action title to mark all announcements as read */
 "announcement.alert.mark all as read" = "Mark all as read";
 
@@ -68,9 +77,6 @@
 /* delete stream download for video */
 "course-item.stream-download-action.delete-download.title" = "Delete video";
 
-/* title to download error alert */
-"course-item.stream-download-action.download-error.title" = "Error while downloading video";
-
 /* start download of stream for video */
 "course-item.stream-download-action.start-download.title" = "Download video";
 

diff --git a/iOS/Data/Model/DocumentLocalization+Download.swift b/iOS/Data/Model/DocumentLocalization+Download.swift
@@ -10,7 +10,7 @@ extension DocumentLocalization: Persistable {
 
     static let identifierKeyPath: WritableKeyPath<DocumentLocalization, String> = \DocumentLocalization.id
 
-    public override func prepareForDeletion() {
+    override public func prepareForDeletion() { // swiftlint:disable:this override_in_extension
         super.prepareForDeletion()
         DocumentsPersistenceManager.shared.prepareForDeletion(of: self)
     }

diff --git a/iOS/Data/Model/Video+Download.swift b/iOS/Data/Model/Video+Download.swift
@@ -10,7 +10,7 @@ extension Video: Persistable {
 
     static let identifierKeyPath: WritableKeyPath<Video, String> = \Video.id
 
-    public override func prepareForDeletion() {
+    override public func prepareForDeletion() { // swiftlint:disable:this override_in_extension
         super.prepareForDeletion()
         StreamPersistenceManager.shared.prepareForDeletion(of: self)
         SlidesPersistenceManager.shared.prepareForDeletion(of: self)

diff --git a/iOS/Helpers/PersistenceManager/DocumentsPersistenceManager.swift b/iOS/Helpers/PersistenceManager/DocumentsPersistenceManager.swift
@@ -10,8 +10,10 @@ import UIKit
 
 final class DocumentsPersistenceManager: NSObject, FilePersistenceManager {
 
-    static var shared = DocumentsPersistenceManager(keyPath: \DocumentLocalization.localFileBookmark)
-    static var downloadType = "documents"
+    static let shared = DocumentsPersistenceManager(keyPath: \DocumentLocalization.localFileBookmark)
+    static let downloadType = "documents"
+    static let titleForFailedDownloadAlert = NSLocalizedString("alert.download-error.documents.title",
+                                                               comment: "title of alert for stream download errors")
 
     lazy var persistentContainerQueue = self.createPersistenceContainerQueue()
     lazy var session: URLSession = self.createURLSession(withIdentifier: "documents-download")
@@ -37,27 +39,6 @@ final class DocumentsPersistenceManager: NSObject, FilePersistenceManager {
         self.startDownload(with: url, for: documentLocalization)
     }
 
-    func didFailToDownloadResource(_ resource: DocumentLocalization, with error: NSError) {
-        ErrorManager.shared.remember((Resource.type, resource.id), forKey: "resource")
-        ErrorManager.shared.report(error)
-        log.error("Unknown asset download error (resource type: \(Resource.type) | resource id: \(resource.id) | domain: \(error.domain) | code: \(error.code)")
-
-        // show error
-        DispatchQueue.main.async {
-            let alertTitle = "Document Download Error"
-            let alertMessage = "Domain: \(error.domain)\nCode: \(error.code)"
-            let alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .alert)
-            let actionTitle = NSLocalizedString("global.alert.ok", comment: "title to confirm alert")
-            alert.addAction(UIAlertAction(title: actionTitle, style: .default) { _ in
-                alert.dismiss(animated: trueUnlessReduceMotionEnabled)
-            })
-
-            let rootViewController = AppDelegate.instance().window?.rootViewController
-            let presentingViewController = rootViewController?.presentedViewController ?? rootViewController
-            presentingViewController?.present(alert, animated: trueUnlessReduceMotionEnabled)
-        }
-    }
-
 }
 
 extension DocumentsPersistenceManager {

diff --git a/iOS/Helpers/PersistenceManager/PersistenceManager.swift b/iOS/Helpers/PersistenceManager/PersistenceManager.swift
@@ -20,6 +20,7 @@ protocol PersistenceManager: AnyObject {
 
     static var shared: Self { get }
     static var downloadType: String { get }
+    static var titleForFailedDownloadAlert: String { get }
 
     var persistentContainerQueue: OperationQueue { get }
     var session: Session { get }
@@ -30,23 +31,10 @@ protocol PersistenceManager: AnyObject {
     var progresses: [String: Double] { get set }
     var didRestorePersistenceManager: Bool { get set }
 
-    // functionality
-    func restoreDownloads()
-    func startDownload(with url: URL, for resource: Resource)
-    func downloadState(for resource: Resource) -> DownloadState
-    func downloadProgress(for resource: Resource) -> Double?
-    func deleteDownload(for resource: Resource)
-    func cancelDownload(for resource: Resource)
-
     func fileSize(for resource: Resource) -> UInt64?
 
-    // callbacks
-    func didCompleteDownloadTask(_ task: URLSessionTask, with error: Error?)
-    func didFinishDownloadTask(_ task: URLSessionTask, to location: URL)
-
     // configuration
     func downloadTask(with url: URL, for resource: Resource, on session: Session) -> URLSessionTask?
-    func didFailToDownloadResource(_ resource: Resource, with error: NSError)
     func resourceModificationAfterStartingDownload(for resource: Resource)
     func resourceModificationAfterDeletingDownload(for resource: Resource)
 
@@ -150,7 +138,7 @@ extension PersistenceManager {
         }
     }
 
-    func deleteDownload(for resource: Resource, in context: NSManagedObjectContext) {
+    private func deleteDownload(for resource: Resource, in context: NSManagedObjectContext) {
         guard let localFileLocation = self.localFileLocation(for: resource) else { return }
 
         let resourceIdentifier = resource[keyPath: Resource.identifierKeyPath]
@@ -307,6 +295,34 @@ extension PersistenceManager {
         }
     }
 
+    func didFailToDownloadResource(_ resource: Resource, with error: NSError) {
+        let resourceId = resource[keyPath: Resource.identifierKeyPath]
+
+        if error.domain == NSURLErrorDomain && error.code == NSURLErrorCancelled {
+            log.debug("Canceled download of resource (type: \(Resource.self) id: \(resourceId))")
+            return
+        }
+
+        ErrorManager.shared.remember((Resource.self, resourceId), forKey: "resource")
+        ErrorManager.shared.report(error)
+        log.error("Unknown asset download error (resource type: \(Resource.self) | resource id: \(resourceId) | domain: \(error.domain) | code: \(error.code)")
+
+        // show error
+        DispatchQueue.main.async {
+            let alertTitle = Self.titleForFailedDownloadAlert
+            let alertMessage = "Domain: \(error.domain)\nCode: \(error.code)"
+            let alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .alert)
+            let actionTitle = NSLocalizedString("global.alert.ok", comment: "title to confirm alert")
+            alert.addAction(UIAlertAction(title: actionTitle, style: .default) { _ in
+                alert.dismiss(animated: trueUnlessReduceMotionEnabled)
+            })
+
+            let rootViewController = AppDelegate.instance().window?.rootViewController
+            let presentingViewController = rootViewController?.presentedViewController ?? rootViewController
+            presentingViewController?.present(alert, animated: trueUnlessReduceMotionEnabled)
+        }
+    }
+
     // MARK: configurations
 
     func resourceModificationAfterStartingDownload(for resource: Resource) {}

diff --git a/iOS/Helpers/PersistenceManager/SlidesPersistenceManager.swift b/iOS/Helpers/PersistenceManager/SlidesPersistenceManager.swift
@@ -10,8 +10,10 @@ import UIKit
 
 final class SlidesPersistenceManager: NSObject, FilePersistenceManager {
 
-    static var shared = SlidesPersistenceManager(keyPath: \Video.localSlidesBookmark)
-    static var downloadType = "slides"
+    static let shared = SlidesPersistenceManager(keyPath: \Video.localSlidesBookmark)
+    static let downloadType = "slides"
+    static let titleForFailedDownloadAlert = NSLocalizedString("alert.download-error.slides.title",
+                                                               comment: "title of alert for slides download errors")
 
     lazy var persistentContainerQueue = self.createPersistenceContainerQueue()
     lazy var session: URLSession = self.createURLSession(withIdentifier: "slides-download")
@@ -56,27 +58,6 @@ final class SlidesPersistenceManager: NSObject, FilePersistenceManager {
         TrackingHelper.shared.createEvent(.slidesDownloadFinished, resourceType: .video, resourceId: resource.id, context: self.trackingContext(for: resource))
     }
 
-    func didFailToDownloadResource(_ resource: Video, with error: NSError) {
-        ErrorManager.shared.remember((Resource.type, resource.id), forKey: "resource")
-        ErrorManager.shared.report(error)
-        log.error("Unknown asset download error (resource type: \(Resource.type) | resource id: \(resource.id) | domain: \(error.domain) | code: \(error.code)")
-
-        // show error
-        DispatchQueue.main.async {
-            let alertTitle = "Slide Download Error"
-            let alertMessage = "Domain: \(error.domain)\nCode: \(error.code)"
-            let alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .alert)
-            let actionTitle = NSLocalizedString("global.alert.ok", comment: "title to confirm alert")
-            alert.addAction(UIAlertAction(title: actionTitle, style: .default) { _ in
-                alert.dismiss(animated: trueUnlessReduceMotionEnabled)
-            })
-
-            let rootViewController = AppDelegate.instance().window?.rootViewController
-            let presentingViewController = rootViewController?.presentedViewController ?? rootViewController
-            presentingViewController?.present(alert, animated: trueUnlessReduceMotionEnabled)
-        }
-    }
-
 }
 
 extension SlidesPersistenceManager {

diff --git a/iOS/Helpers/PersistenceManager/StreamPersistenceManager.swift b/iOS/Helpers/PersistenceManager/StreamPersistenceManager.swift
@@ -13,8 +13,10 @@ final class StreamPersistenceManager: NSObject, PersistenceManager {
 
     typealias Session = AVAssetDownloadURLSession
 
-    static var shared = StreamPersistenceManager()
-    static var downloadType = "stream"
+    static let shared = StreamPersistenceManager()
+    static let downloadType = "stream"
+    static let titleForFailedDownloadAlert = NSLocalizedString("alert.download-error.stream.title",
+                                                               comment: "title of alert for stream download errors")
 
     let keyPath: ReferenceWritableKeyPath<Video, NSData?> = \Video.localFileBookmark
 
@@ -81,33 +83,6 @@ final class StreamPersistenceManager: NSObject, PersistenceManager {
         TrackingHelper.shared.createEvent(.videoDownloadFinished, resourceType: .video, resourceId: resource.id, context: self.trackingContext(for: resource))
     }
 
-    func didFailToDownloadResource(_ resource: Video, with error: NSError) {
-        if error.domain == NSURLErrorDomain && error.code == NSURLErrorCancelled {
-            log.debug("Canceled download of video (video id: \(resource.id))")
-            return
-        }
-
-        ErrorManager.shared.remember((Resource.type, resource.id), forKey: "resource")
-        ErrorManager.shared.report(error)
-        log.error("Unknown asset download error (video id: \(resource.id) | domain: \(error.domain) | code: \(error.code)")
-
-        // show error
-        DispatchQueue.main.async {
-            let alertTitle = NSLocalizedString("course-item.stream-download-action.download-error.title",
-                                               comment: "title to download error alert")
-            let alertMessage = "Domain: \(error.domain)\nCode: \(error.code)"
-            let alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .alert)
-            let actionTitle = NSLocalizedString("global.alert.ok", comment: "title to confirm alert")
-            alert.addAction(UIAlertAction(title: actionTitle, style: .default) { _ in
-                alert.dismiss(animated: trueUnlessReduceMotionEnabled)
-            })
-
-            let rootViewController = AppDelegate.instance().window?.rootViewController
-            let presentingViewController = rootViewController?.presentedViewController ?? rootViewController
-            presentingViewController?.present(alert, animated: trueUnlessReduceMotionEnabled)
-        }
-    }
-
 }
 
 extension StreamPersistenceManager {

diff --git a/iOS/de.lproj/Localizable.strings b/iOS/de.lproj/Localizable.strings
@@ -1,4 +1,13 @@
 
+/* title of alert for stream download errors */
+"alert.download-error.documents.title" = "Fehler beim Dokument-Download";
+
+/* title of alert for slides download errors */
+"alert.download-error.slides.title" = "Fehler beim Folien-Download";
+
+/* title of alert for stream download errors */
+"alert.download-error.stream.title" = "Fehler beim Video-Download";
+
 /* alert action title to mark all announcements as read */
 "announcement.alert.mark all as read" = "Alle als gelesen markieren";
 
@@ -68,9 +77,6 @@
 /* delete stream download for video */
 "course-item.stream-download-action.delete-download.title" = "Video löschen";
 
-/* title to download error alert */
-"course-item.stream-download-action.download-error.title" = "Fehler beim Video-Download";
-
 /* start download of stream for video */
 "course-item.stream-download-action.start-download.title" = "Video herunterladen";