Akka.Actor: make ITimeProvider injectable into consuming classes (#…

…7314)

* remove `DateTimeNowTimeProvider`

All of this functionality was duplicated on the `IScheduler` anyway - so removing this makes it possible to actually inject the `ITimeProvider` into downstream dependencies using the `ActorSystem`

* added `DateTimeNowTimeProvider` back but marked it as `Obsolete`

src/contrib/cluster/Akka.Cluster.Sharding/Delivery/Internal/ShardingProducerControllerImpl.cs

@@ -50,7 +50,7 @@ public ShardingProducerController(string producerId, IActorRef shardRegion, Opti
         ShardRegion = shardRegion;
         _durableQueueProps = durableQueueProps;
         Settings = settings;
-        _timeProvider = timeProvider ?? DateTimeOffsetNowTimeProvider.Instance;
+        _timeProvider = timeProvider ?? Context.System.Scheduler;
 
         WaitingForStart(Option<IActorRef>.None, CreateInitialState(_durableQueueProps.HasValue));
     }

src/core/Akka.API.Tests/verify/CoreAPISpec.ApproveCore.DotNet.verified.txt

@@ -589,6 +589,7 @@ namespace Akka.Actor
         public CoordinatedShutdownExtension() { }
         public override Akka.Actor.CoordinatedShutdown CreateExtension(Akka.Actor.ExtendedActorSystem system) { }
     }
+    [System.ObsoleteAttribute("This class will be removed in Akka.NET v1.6.0 - use the IScheduler instead.")]
     public class DateTimeOffsetNowTimeProvider : Akka.Actor.IDateTimeOffsetNowTimeProvider, Akka.Actor.ITimeProvider
     {
         public System.TimeSpan HighResMonotonicClock { get; }

src/core/Akka.API.Tests/verify/CoreAPISpec.ApproveCore.Net.verified.txt

@@ -589,6 +589,7 @@ namespace Akka.Actor
         public CoordinatedShutdownExtension() { }
         public override Akka.Actor.CoordinatedShutdown CreateExtension(Akka.Actor.ExtendedActorSystem system) { }
     }
+    [System.ObsoleteAttribute("This class will be removed in Akka.NET v1.6.0 - use the IScheduler instead.")]
     public class DateTimeOffsetNowTimeProvider : Akka.Actor.IDateTimeOffsetNowTimeProvider, Akka.Actor.ITimeProvider
     {
         public System.TimeSpan HighResMonotonicClock { get; }

src/core/Akka.Persistence/Delivery/EventSourcedProducerQueue.cs

@@ -141,7 +141,7 @@ public EventSourcedProducerQueue(string persistenceId, EventSourcedProducerQueue
     {
         PersistenceId = persistenceId;
         Settings = settings ?? EventSourcedProducerQueue.Settings.Create(Context.System);
-        _timeProvider = timeProvider ?? DateTimeOffsetNowTimeProvider.Instance;
+        _timeProvider = timeProvider ?? Context.System.Scheduler;
         JournalPluginId = Settings.JournalPluginId;
         SnapshotPluginId = Settings.SnapshotPluginId;
         Self.Tell(EventSourcedProducerQueue.CleanupTick.Instance);

src/core/Akka/Actor/Scheduler/DateTimeNowTimeProvider.cs

@@ -10,29 +10,19 @@
 namespace Akka.Actor
 {
     /// <summary>
-    /// TBD
+    /// The default <see cref="ITimeProvider"/> implementation for Akka.NET when not testing.
     /// </summary>
-    public class DateTimeOffsetNowTimeProvider : ITimeProvider, IDateTimeOffsetNowTimeProvider
+    [Obsolete("This class will be removed in Akka.NET v1.6.0 - use the IScheduler instead.")]
+    public class DateTimeOffsetNowTimeProvider : IDateTimeOffsetNowTimeProvider
     {
         private DateTimeOffsetNowTimeProvider() { }
-        /// <summary>
-        /// TBD
-        /// </summary>
+
         public DateTimeOffset Now { get { return DateTimeOffset.UtcNow; } }
-
-        /// <summary>
-        /// TBD
-        /// </summary>
+
         public TimeSpan MonotonicClock {get { return Util.MonotonicClock.Elapsed; }}
-
-        /// <summary>
-        /// TBD
-        /// </summary>
+
         public TimeSpan HighResMonotonicClock{get { return Util.MonotonicClock.ElapsedHighRes; }}
-
-        /// <summary>
-        /// TBD
-        /// </summary>
+
         public static DateTimeOffsetNowTimeProvider Instance { get; } = new();
     }
 }

src/core/Akka/Actor/Scheduler/ITimeProvider.cs

@@ -10,8 +10,13 @@
 namespace Akka.Actor
 {
     /// <summary>
-    /// TBD
+    /// Time provider used by the scheduler to obtain the current time.
     /// </summary>
+    /// <remarks>
+    /// Intended to be customizable to we can virtualize time for testing purposes.
+    ///
+    /// In the future we will drop this in favor of the time provider built into .NET 8 and later.
+    /// </remarks>
     public interface ITimeProvider
     {
         /// <summary>

src/core/Akka/Delivery/Internal/ProducerControllerImpl.cs

@@ -57,7 +57,7 @@ public ProducerController(string producerId,
         ProducerId = producerId;
         Settings = settings ?? ProducerController.Settings.Create(Context.System);
         _durableProducerQueueProps = durableProducerQueue;
-        _timeProvider = timeProvider ?? DateTimeOffsetNowTimeProvider.Instance;
+        _timeProvider = timeProvider ?? Context.System.Scheduler;
         _fuzzingControl = fuzzingControl;
 
         // this state gets overridden during the loading sequence, so it's not used at all really
@@ -86,7 +86,7 @@ public ProducerController(string producerId,
         ProducerId = producerId;
         Settings = settings ?? ProducerController.Settings.Create(Context.System);
         _durableProducerQueueProps = durableProducerQueue;
-        _timeProvider = timeProvider ?? DateTimeOffsetNowTimeProvider.Instance;
+        _timeProvider = timeProvider ?? Context.System.Scheduler;
         _fuzzingControl = fuzzingControl;
 
         // this state gets overridden during the loading sequence, so it's not used at all really

src/core/Akka/Delivery/ProducerController.cs

@@ -82,9 +82,9 @@ private static Props ProducerControllerProps<T>(ActorSystem actorSystem, string
     {
         if (sendAdapter == null)
             return Props.Create(() => new ProducerController<T>(producerId, durableProducerQueue, settings,
-                DateTimeOffsetNowTimeProvider.Instance, fuzzing));
+                actorSystem.Scheduler, fuzzing));
         return Props.Create(() => new ProducerController<T>(producerId, durableProducerQueue, sendAdapter, settings,
-            DateTimeOffsetNowTimeProvider.Instance, fuzzing));
+            actorSystem.Scheduler, fuzzing));
     }
 
     public sealed record Settings