Improved PeriodicTask to use .NET 6 PeriodicTimer under the hood

Author: ashneilson

RICADO.Threading/PeriodicFactory.cs

@@ -31,7 +31,7 @@ public PeriodicFactory()
         #region Public Methods
 
         /// <summary>
-        /// Create a new <see cref="PeriodicTimer"/>
+        /// Create a new <see cref="PeriodicSyncTimer"/>
         /// </summary>
         /// <param name="name">A Name for the Timer</param>
         /// <param name="action">The Method to be periodically called</param>
@@ -40,7 +40,7 @@ public PeriodicFactory()
         /// <returns>The Name of the new Timer</returns>
         /// <exception cref="System.ArgumentNullException"></exception>
         /// <exception cref="System.ArgumentException"></exception>
-        public string CreateNew(string name, Action action, int interval, int startDelay = 0)
+        public string CreateNew(string? name, Action action, int interval, int startDelay = 0)
         {
             if(name == null)
             {
@@ -57,13 +57,13 @@ public string CreateNew(string name, Action action, int interval, int startDelay
                 throw new ArgumentException("The Specified Name has already been used by another Periodic Item", nameof(name));
             }
 
-            _periodicItems.TryAdd(name, new PeriodicTimer(action, interval, startDelay));
+            _periodicItems.TryAdd(name, new PeriodicSyncTimer(action, interval, startDelay));
 
             return name;
         }
 
         /// <summary>
-        /// Create a new <see cref="PeriodicTimer"/>
+        /// Create a new <see cref="PeriodicSyncTimer"/>
         /// </summary>
         /// <param name="action">The Method to be periodically called</param>
         /// <param name="interval">The Interval between Method calls in Milliseconds</param>
@@ -86,7 +86,7 @@ public string CreateNew(Action action, int interval, int startDelay = 0)
         /// <returns>The Name of the new Task</returns>
         /// <exception cref="System.ArgumentNullException"></exception>
         /// <exception cref="System.ArgumentException"></exception>
-        public string CreateNew(string name, Func<CancellationToken, Task> action, int interval, int startDelay = 0)
+        public string CreateNew(string? name, Func<CancellationToken, Task> action, int interval, int startDelay = 0)
         {
             if (name == null)
             {

RICADO.Threading/PeriodicTask.cs

@@ -9,16 +9,21 @@ public sealed class PeriodicTask : IPeriodic, IDisposable
     {
         #region Private Properties
 
-        private Task _task;
+        private PeriodicTimer _timer;
+        
+        private Task? _task;
 
-        private Func<CancellationToken, Task> _action;
+        private readonly Func<CancellationToken, Task> _action;
 
         private CancellationTokenSource _stoppingCts;
 
         private int _interval = Timeout.Infinite;
 
         private int _startDelay = Timeout.Infinite;
 
+        private bool _running = false;
+        private readonly object _runningLock = new object();
+
         #endregion
 
 
@@ -65,12 +70,7 @@ public int StartDelay
         /// <exception cref="System.ArgumentOutOfRangeException"></exception>
         public PeriodicTask(Func<CancellationToken, Task> action, int interval, int startDelay = 0)
         {
-            if (action == null)
-            {
-                throw new ArgumentNullException(nameof(action));
-            }
-
-            _action = action;
+            _action = action ?? throw new ArgumentNullException(nameof(action));
 
             if (interval < 0)
             {
@@ -85,6 +85,10 @@ public PeriodicTask(Func<CancellationToken, Task> action, int interval, int star
             }
 
             _startDelay = startDelay;
+
+            _timer = new PeriodicTimer(TimeSpan.FromMilliseconds(_interval));
+
+            _stoppingCts = new CancellationTokenSource();
         }
 
         #endregion
@@ -97,11 +101,23 @@ public PeriodicTask(Func<CancellationToken, Task> action, int interval, int star
         /// </summary>
         public Task Start()
         {
+            lock (_runningLock)
+            {
+                if (_running == true)
+                {
+                    return Task.CompletedTask;
+                }
+
+                _running = true;
+            }
+
             if (_task != null)
             {
                 return Task.CompletedTask;
             }
 
+            _timer = new PeriodicTimer(TimeSpan.FromMilliseconds(_interval));
+
             _stoppingCts = new CancellationTokenSource();
 
             try
@@ -118,27 +134,49 @@ public Task Start()
         /// <summary>
         /// Stop the <see cref="PeriodicTask"/>
         /// </summary>
-        public Task Stop()
+        public async Task Stop()
         {
-            if(_stoppingCts != null)
+            lock (_runningLock)
             {
-                _stoppingCts.Cancel();
+                if (_running == false)
+                {
+                    return;
+                }
+
+                _running = false;
             }
 
-            if(_task == null)
+            _stoppingCts.Cancel();
+
+            _timer.Dispose();
+
+            if (_task == null)
             {
-                return Task.CompletedTask;
+                return;
             }
 
-            return _task;
+            try
+            {
+                await _task;
+            }
+            catch (OperationCanceledException)
+            {
+            }
         }
 
         /// <summary>
         /// Release all resources used by the current instance of <see cref="PeriodicTask"/>
         /// </summary>
         public void Dispose()
         {
-            _stoppingCts?.Dispose();
+            lock (_runningLock)
+            {
+                _running = false;
+            }
+
+            _stoppingCts.Dispose();
+
+            _timer.Dispose();
         }
 
         #endregion
@@ -169,27 +207,24 @@ private async Task taskRunner()
                 }
             }
 
-            while(_stoppingCts.Token.IsCancellationRequested == false)
+            while(await _timer.WaitForNextTickAsync(_stoppingCts.Token) == true)
             {
-                try
-                {
-                    await _action(_stoppingCts.Token).ConfigureAwait(false);
-                }
-                catch (OperationCanceledException)
+                lock(_runningLock)
                 {
-                    if (_stoppingCts.IsCancellationRequested)
+                    if(_running == false)
                     {
-                        throw;
+                        return;
                     }
                 }
-                catch (Exception e)
+
+                if(_stoppingCts.IsCancellationRequested == true)
                 {
-                    Logger.LogCritical(e, "Unhandled Exception on the Periodic Task Action Method");
+                    return;
                 }
-
+                
                 try
                 {
-                    await Task.Delay(_interval, _stoppingCts.Token).ConfigureAwait(false);
+                    await _action(_stoppingCts.Token).ConfigureAwait(false);
                 }
                 catch (OperationCanceledException)
                 {
@@ -198,8 +233,9 @@ private async Task taskRunner()
                         throw;
                     }
                 }
-                catch
+                catch (Exception e)
                 {
+                    Logger.LogCritical(e, "Unhandled Exception on the Periodic Task Action Method");
                 }
             }
         }

RICADO.Threading/RICADO.Threading.csproj

@@ -12,6 +12,8 @@
     <IncludeSymbols>true</IncludeSymbols>
     <SymbolPackageFormat>snupkg</SymbolPackageFormat>
     <AllowedOutputExtensionsInPackageBuildOutputFolder>$(AllowedOutputExtensionsInPackageBuildOutputFolder);.pdb</AllowedOutputExtensionsInPackageBuildOutputFolder>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>