Persistent setting storage

Author: Maximilian Krauss

Winfy.Core/JsonPersister.cs

@@ -0,0 +1,40 @@
+using System;
+using System.IO;
+using System.Timers;
+
+namespace Winfy.Core {
+    public sealed class JsonPersister<T> : IDisposable where T : class {
+        
+        private T _Instance;
+        private readonly Timer _Persistor;
+        private readonly object _SyncLock;
+
+        public JsonPersister(string path) {
+            Path = path;
+            _SyncLock = new object();
+            _Persistor = new Timer(new TimeSpan(0, 0, 1, 0).TotalMilliseconds) {AutoReset = true, Enabled = true};
+            _Persistor.Elapsed += (o, e) => Persist();
+        }
+
+        public string Path { get; private set; }
+
+        public T Instance {
+            get {
+                return _Instance ?? (_Instance = File.Exists(Path)
+                                                     ? Serializer.DeserializeFromJson<T>(Path)
+                                                     : Activator.CreateInstance<T>());
+            }
+        }
+
+        public void Persist() {
+            lock (_SyncLock) {
+                Serializer.SerializeToJson(_Instance, Path);
+            }
+        }
+
+        public void Dispose() {
+            _Persistor.Dispose();
+            Persist();
+        }
+    }
+}

Winfy.Core/Serializer.cs

@@ -35,6 +35,12 @@ public static T DeserializeFromXml<T>(byte[] data) {
         }
 
         public static void SerializeToJson<T>(T instance, string filename) {
+            if(string.IsNullOrEmpty(filename))
+                throw new ArgumentException("filename");
+
+            if (!Directory.Exists(Path.GetDirectoryName(filename)))
+                Directory.CreateDirectory(Path.GetDirectoryName(filename));
+
             File.WriteAllBytes(filename, SerializeToJson(instance));
         }
         public static byte[] SerializeToJson<T>(T instance) {

Winfy.Core/Winfy.Core.csproj

@@ -79,6 +79,7 @@
     <Compile Include="ILog.cs" />
     <Compile Include="ISpotifyController.cs" />
     <Compile Include="IUsageTrackerService.cs" />
+    <Compile Include="JsonPersister.cs" />
     <Compile Include="LastFmPOCOs.cs" />
     <Compile Include="LocalUsageTrackerService.cs" />
     <Compile Include="ProductionLogger.cs" />

Winfy/AppBootstrapper.cs

@@ -15,7 +15,7 @@ public sealed class AppBootstrapper : TinyBootstrapper<ShellViewModel> {
 
         private AppSettings _Settings;
         private AppContracts _Contracts;
-        private string _SettingsPath;
+        private JsonPersister<AppSettings> _SettingsPersistor;
 
         protected override void OnStartup(object sender, System.Windows.StartupEventArgs e) {
             base.OnStartup(sender, e);
@@ -29,12 +29,11 @@ protected override void Configure() {
             base.Configure();
 
             _Contracts = new AppContracts();
-            _SettingsPath = Path.Combine(_Contracts.SettingsLocation, _Contracts.SettingsFilename);
-            _Settings = File.Exists(_SettingsPath)
-                            ? Serializer.DeserializeFromJson<AppSettings>(_SettingsPath)
-                            : new AppSettings();
 
 
+            _SettingsPersistor = new JsonPersister<AppSettings>(Path.Combine(_Contracts.SettingsLocation, _Contracts.SettingsFilename));
+            _Settings = _SettingsPersistor.Instance;
+
             Container.Register<AppContracts>(_Contracts);
             Container.Register<AppSettings>(_Settings);
             Container.Register<Core.ILog>(new ProductionLogger());
@@ -53,7 +52,7 @@ protected override void Configure() {
 
         protected override void OnExit(object sender, EventArgs e) {
             base.OnExit(sender, e);
-            Serializer.SerializeToJson(_Settings, _SettingsPath);
+            _SettingsPersistor.Dispose();
         }
     }
 }

Winfy/changelog.json

@@ -4,7 +4,8 @@
 		"description": "yay 2.0",
 		"changes": [
 			"Major version jump to 2.0. Chrome style, whoop whoop :)",
-			"New: Winfy now utilizes the Spotify local API for better cover image support"
+			"New: Winfy utilizes the Spotify local API for better cover image support",
+			"Improved: Auto-save for app settings every minute"
 		]
 	},
 	{