Use os logging framework, so logs can be retrieved later

ios/App/App.xcodeproj/project.pbxproj

@@ -60,6 +60,7 @@
 		E9D5507528AEF93100C746DD /* PlayerSettings.swift in Sources */ = {isa = PBXBuildFile; fileRef = E9D5507428AEF93100C746DD /* PlayerSettings.swift */; };
 		E9DFCBFB28C28F4A00B36356 /* AudioPlayerSleepTimer.swift in Sources */ = {isa = PBXBuildFile; fileRef = E9DFCBFA28C28F4A00B36356 /* AudioPlayerSleepTimer.swift */; };
 		E9E985F828B02D9400957F23 /* PlayerProgress.swift in Sources */ = {isa = PBXBuildFile; fileRef = E9E985F728B02D9400957F23 /* PlayerProgress.swift */; };
+		E9FA07E328C82848005520B0 /* Logger.swift in Sources */ = {isa = PBXBuildFile; fileRef = E9FA07E228C82848005520B0 /* Logger.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -120,6 +121,7 @@
 		E9D5507428AEF93100C746DD /* PlayerSettings.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PlayerSettings.swift; sourceTree = "<group>"; };
 		E9DFCBFA28C28F4A00B36356 /* AudioPlayerSleepTimer.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AudioPlayerSleepTimer.swift; sourceTree = "<group>"; };
 		E9E985F728B02D9400957F23 /* PlayerProgress.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PlayerProgress.swift; sourceTree = "<group>"; };
+		E9FA07E228C82848005520B0 /* Logger.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Logger.swift; sourceTree = "<group>"; };
 		FC68EB0AF532CFC21C3344DD /* Pods-App.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-App.debug.xcconfig"; path = "Pods/Target Support Files/Pods-App/Pods-App.debug.xcconfig"; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
@@ -199,6 +201,7 @@
 		3AFCB5E627EA23F700ECCC05 /* util */ = {
 			isa = PBXGroup;
 			children = (
+				E9FA07E228C82848005520B0 /* Logger.swift */,
 				3AFCB5E727EA240D00ECCC05 /* NowPlayingInfo.swift */,
 				3AD4FCEA280443DD006DB301 /* Database.swift */,
 				3AD4FCEC28044E6C006DB301 /* Store.swift */,
@@ -412,6 +415,7 @@
 				E9D5506228AC1CC900C746DD /* PlayerState.swift in Sources */,
 				3AD4FCE728043E72006DB301 /* AbsDatabase.m in Sources */,
 				504EC3081FED79650016851F /* AppDelegate.swift in Sources */,
+				E9FA07E328C82848005520B0 /* Logger.swift in Sources */,
 				3A90295F280968E700E1D427 /* PlaybackReport.swift in Sources */,
 				E9D5505A28AC1C4500C746DD /* Folder.swift in Sources */,
 				3ABF580928059BAE005DFBE5 /* PlaybackSession.swift in Sources */,

ios/App/Shared/player/PlayerProgress.swift

@@ -14,6 +14,8 @@ class PlayerProgress {
     
     private static let TIME_BETWEEN_SESSION_SYNC_IN_SECONDS = 10.0
     
+    private let logger = AppLogger(category: "PlayerProgress")
+    
     private init() {}
     
     
@@ -28,8 +30,8 @@ class PlayerProgress {
                 try await updateServerSessionFromLocalSession(session, rateLimitSync: !isStopping)
             }
         } catch {
-            debugPrint("Failed to syncFromPlayer")
+            logger.error("Failed to syncFromPlayer")
-            debugPrint(error)
+            logger.error(error)
         }
         await UIApplication.shared.endBackgroundTask(backgroundToken)
     }
@@ -39,8 +41,8 @@ class PlayerProgress {
         do {
             try await updateAllServerSessionFromLocalSession()
         } catch {
-            debugPrint("Failed to syncToServer")
+            logger.error("Failed to syncToServer")
-            debugPrint(error)
+            logger.error(error)
         }
         await UIApplication.shared.endBackgroundTask(backgroundToken)
     }
@@ -50,8 +52,8 @@ class PlayerProgress {
         do {
             try await updateLocalSessionFromServerMediaProgress()
         } catch {
-            debugPrint("Failed to syncFromServer")
+            logger.error("Failed to syncFromServer")
-            debugPrint(error)
+            logger.error(error)
         }
         await UIApplication.shared.endBackgroundTask(backgroundToken)
     }
@@ -96,7 +98,7 @@ class PlayerProgress {
 
         try localMediaProgress.updateFromPlaybackSession(session)
         
-        NSLog("Local progress saved to the database")
+        logger.debug("Local progress saved to the database")
         
         // Send the local progress back to front-end
         NotificationCenter.default.post(name: NSNotification.Name(PlayerEvents.localProgress.rawValue), object: nil)
@@ -141,7 +143,7 @@ class PlayerProgress {
         session = session.freeze()
         
         guard safeToSync else { return }
-        NSLog("Sending sessionId(\(session.id)) to server with currentTime(\(session.currentTime))")
+        logger.debug("Sending sessionId(\(session.id)) to server with currentTime(\(session.currentTime))")
         
         var success = false
         if session.isLocal {
@@ -161,25 +163,25 @@ class PlayerProgress {
     }
     
     private func updateLocalSessionFromServerMediaProgress() async throws {
-        NSLog("updateLocalSessionFromServerMediaProgress: Checking if local media progress was updated on server")
+        logger.debug("updateLocalSessionFromServerMediaProgress: Checking if local media progress was updated on server")
         guard let session = try await Realm().objects(PlaybackSession.self).last(where: {
             $0.isActiveSession == true && $0.serverConnectionConfigId == Store.serverConfig?.id
         })?.freeze() else {
-            NSLog("updateLocalSessionFromServerMediaProgress: Failed to get session")
+            logger.debug("updateLocalSessionFromServerMediaProgress: Failed to get session")
             return
         }
         
         // Fetch the current progress
         let progress = await ApiClient.getMediaProgress(libraryItemId: session.libraryItemId!, episodeId: session.episodeId)
         guard let progress = progress else {
-            NSLog("updateLocalSessionFromServerMediaProgress: No progress object")
+            logger.debug("updateLocalSessionFromServerMediaProgress: No progress object")
             return
         }
         
         // Determine which session is newer
         let serverLastUpdate = progress.lastUpdate
         guard let localLastUpdate = session.updatedAt else {
-            NSLog("updateLocalSessionFromServerMediaProgress: No local session updatedAt")
+            logger.debug("updateLocalSessionFromServerMediaProgress: No local session updatedAt")
             return
         }
         let serverCurrentTime = progress.currentTime
@@ -190,16 +192,16 @@ class PlayerProgress {
         
         // Update the session, if needed
         if serverIsNewerThanLocal && currentTimeIsDifferent {
-            NSLog("updateLocalSessionFromServerMediaProgress: Server has newer time than local serverLastUpdate=\(serverLastUpdate) localLastUpdate=\(localLastUpdate)")
+            logger.debug("updateLocalSessionFromServerMediaProgress: Server has newer time than local serverLastUpdate=\(serverLastUpdate) localLastUpdate=\(localLastUpdate)")
             guard let session = session.thaw() else { return }
             try session.update {
                 session.currentTime = serverCurrentTime
                 session.updatedAt = serverLastUpdate
             }
-            NSLog("updateLocalSessionFromServerMediaProgress: Updated session currentTime newCurrentTime=\(serverCurrentTime) previousCurrentTime=\(localCurrentTime)")
+            logger.debug("updateLocalSessionFromServerMediaProgress: Updated session currentTime newCurrentTime=\(serverCurrentTime) previousCurrentTime=\(localCurrentTime)")
             PlayerHandler.seek(amount: session.currentTime)
         } else {
-            NSLog("updateLocalSessionFromServerMediaProgress: Local session does not need updating; local has latest progress")
+            logger.debug("updateLocalSessionFromServerMediaProgress: Local session does not need updating; local has latest progress")
         }
     }
     

ios/App/Shared/util/Logger.swift

@@ -0,0 +1,76 @@
+//
+//  AppLogger.swift
+//  AppLogger
+//
+//  Created by Fernando Fernandes on 29.06.20.
+//
+
+import Foundation
+import os
+
+/// Logs app info by using the newest Swift unified logging APIs.
+///
+/// Reference:
+///  - [Explore logging in Swift (WWDC20)](https://developer.apple.com/wwdc20/10168)
+///  - [Unified Logging](https://developer.apple.com/documentation/os/logging)
+///  - [OSLog](https://developer.apple.com/documentation/os/oslog)
+///  - [Logger](https://developer.apple.com/documentation/os/logger)
+public struct AppLogger {
+
+    // MARK: - Properties
+
+    /// Default values used by the `AppLogger`.
+    public struct Defaults {
+        public static let subsystem = Bundle.main.bundleIdentifier ?? "ABS"
+        public static let category = "default"
+        public static let isPrivate = false
+    }
+
+    // MARK: - Private Properties
+
+    private let logger: Logger
+
+    // MARK: - Lifecycle
+
+    /// Creates an `AppLogger` instance.
+    ///
+    /// - Parameters:
+    ///   - subsystem: `String`. Organizes large topic areas within the app or apps. For example, you might define
+    ///   a subsystem for each process that you create. The default is `Bundle.main.bundleIdentifier ?? "AppLogger"`.
+    ///   - category: `String`. Within a `subsystem`, you define categories to further distinguish parts of that
+    ///   subsystem. For example, if you used a single subsystem for your app, you might create separate categories for
+    ///   model code and user-interface code. In a game, you might use categories to distinguish between physics, AI,
+    ///   world simulation, and rendering. The default is `default`.
+    public init(subsystem: String = Defaults.subsystem, category: String = Defaults.category) {
+        self.logger = Logger(subsystem: subsystem, category: category)
+    }
+}
+
+// MARK: - Interface
+
+public extension AppLogger {
+    
+    func log(_ information: String, isPrivate: Bool = Defaults.isPrivate) {
+        if isPrivate {
+            logger.debug("\(information, privacy: .private)")
+        } else {
+            logger.debug("\(information, privacy: .public)")
+        }
+    }
+    
+    func debug(_ information: String, isPrivate: Bool = Defaults.isPrivate) {
+        this.log(information, isPrivate)
+    }
+    
+    func error(_ information: String, isPrivate: Bool = Defaults.isPrivate) {
+        if isPrivate {
+            logger.error("\(information, privacy: .private)")
+        } else {
+            logger.error("\(information, privacy: .public)")
+        }
+    }
+    
+    func error(_ error: Error) {
+        logger.error("\(String(describing: error))")
+    }
+}