Fixes for command scheduling

src/Shiny.Mediator/RegistrationExtensions.cs

@@ -70,6 +70,7 @@ public static ShinyConfigurator AddCommandScheduling<TScheduler>(this ShinyConfi
     {
         configurator.Services.AddSingleton<ICommandScheduler, TScheduler>();
         configurator.AddOpenCommandMiddleware(typeof(ScheduledCommandMiddleware<>));
+        configurator.Services.TryAddSingleton(TimeProvider.System);
         return configurator;
     }
 

src/Shiny.Mediator/Services/Impl/InMemoryCommandScheduler.cs

@@ -8,15 +8,25 @@ namespace Shiny.Mediator.Services.Impl;
 public class InMemoryCommandScheduler : ICommandScheduler
 {
     readonly List<CommandContext> commands = new();
+    readonly TimeProvider timeProvider;
     readonly ILogger logger;
     readonly IMediator mediator;
     readonly Timer timer = new();
 
 
-    public InMemoryCommandScheduler(IMediator mediator, ILogger<ICommandScheduler> logger)
+    public InMemoryCommandScheduler(
+        IMediator mediator, 
+        ILogger<ICommandScheduler> logger,
+        TimeProvider timeProvider
+    )
     {
         this.mediator = mediator;
         this.logger = logger;
+
+        // TODO: timeprovider
+        this.timeProvider = timeProvider;
+
+        // var tt = this.timeProvider.CreateTimer(null, null, TimeSpan.Zero, TimeSpan.FromSeconds(30));
         this.timer.Interval = TimeSpan.FromSeconds(15).TotalMilliseconds;
         this.timer.Elapsed += this.OnTimerElapsed;
     }
@@ -52,7 +62,7 @@ protected virtual async void OnTimerElapsed(object? sender, ElapsedEventArgs e)
         foreach (var item in items)
         {
             var command = (IScheduledCommand)item.Command;
-            if (command.DueAt >= DateTimeOffset.UtcNow)
+            if (command.DueAt < this.timeProvider.GetUtcNow())
             {
                 var headers = item
                     .Values
@@ -64,7 +74,6 @@ protected virtual async void OnTimerElapsed(object? sender, ElapsedEventArgs e)
                     await this.mediator
                         .Send(command, CancellationToken.None, headers)
                         .ConfigureAwait(false);
-
                 }
                 catch (Exception ex)
                 {

src/Shiny.Mediator/Utils.cs

@@ -45,6 +45,7 @@ public static class Utils
         }
         return result;
     }
+
 
     public static TAttribute? GetHandlerHandleMethodAttribute<TCommand, TAttribute>(this ICommandHandler handler) where TAttribute : Attribute where TCommand : ICommand
         => handler

tests/Shiny.Mediator.Tests/AttributeTests.cs

@@ -0,0 +1,6 @@
+namespace Shiny.Mediator.Tests;
+
+public class AttributeTests
+{
+
+}

tests/Shiny.Mediator.Tests/CommandSchedulingTests.cs

@@ -0,0 +1,51 @@
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Time.Testing;
+using Xunit.Abstractions;
+
+namespace Shiny.Mediator.Tests;
+
+public class CommandSchedulingTests(ITestOutputHelper output)
+{
+    [Fact]
+    public async Task EndToEndTest()
+    {
+        MyScheduleCommandHandler.Received = false;
+
+        var services = new ServiceCollection();
+        var time = new FakeTimeProvider();
+
+        services.AddSingleton<TimeProvider>(time);
+        services.AddShinyMediator(x =>
+        {
+            x.AddInMemoryCommandScheduling();
+        }, false);
+        services.AddLogging(x => x.AddXUnit(output));
+        services.AddSingletonAsImplementedInterfaces<MyScheduleCommandHandler>();
+
+        var sp = services.BuildServiceProvider();
+        var mediator = sp.GetRequiredService<IMediator>();
+        await mediator.Send(new MySchedule
+        {
+            DueAt = DateTimeOffset.UtcNow.AddMinutes(1)
+        });
+        MyScheduleCommandHandler.Received.ShouldBeFalse();
+        time.Advance(TimeSpan.FromMinutes(1.5));
+
+        await Task.Delay(1000); // let the thing execute now
+        MyScheduleCommandHandler.Received.ShouldBeTrue();
+    }
+}
+
+public class MySchedule : IScheduledCommand
+{
+    public DateTimeOffset DueAt { get; set; }
+}
+
+public class MyScheduleCommandHandler : ICommandHandler<MySchedule>
+{
+    public static bool Received { get; set; }
+    public async Task Handle(MySchedule command, CommandContext<MySchedule> context, CancellationToken cancellationToken)
+    {
+        Received = true;
+    }
+}

tests/Shiny.Mediator.Tests/Shiny.Mediator.Tests.csproj

@@ -18,6 +18,7 @@
         <PackageReference Include="Microsoft.CodeAnalysis.Common" Version="4.11.0" PrivateAssets="all"/>
         <PackageReference Include="Microsoft.Data.Sqlite" Version="9.0.0"/>
         <PackageReference Include="Microsoft.Extensions.Configuration" Version="9.0.0"/>
+        <PackageReference Include="Microsoft.Extensions.TimeProvider.Testing" Version="9.1.0" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0"/>
         <PackageReference Include="MartinCostello.Logging.XUnit" Version="0.5.1"/>
         <PackageReference Include="Npgsql" Version="9.0.2"/>