Implement Started and Completed execution events

src/modules/Elsa.Workflows.Core/Activities/Flowchart.cs

@@ -28,7 +28,7 @@ public class Flowchart : Container
     
     private async ValueTask OnDescendantCompletedAsync(ActivityCompleted signal, SignalContext context)
     {
-        await ScheduleChildrenAsync(context.ActivityExecutionContext, context.SourceActivityExecutionContext.Activity);
+        await ScheduleChildrenAsync(context.ReceiverActivityExecutionContext, context.SenderActivityExecutionContext.Activity);
     }
 
     private async Task ScheduleChildrenAsync(ActivityExecutionContext context, IActivity parent)

src/modules/Elsa.Workflows.Core/Activities/Sequence.cs

@@ -54,6 +54,6 @@ public class Sequence : Container
     private void OnBreak(BreakSignal signal, SignalContext context)
     {
         // Clear any scheduled child completion callbacks, since we no longer want to schedule any sibling. 
-        context.ActivityExecutionContext.ClearCompletionCallbacks();
+        context.ReceiverActivityExecutionContext.ClearCompletionCallbacks();
     }
 }

src/modules/Elsa.Workflows.Core/Behaviors/BreakBehavior.cs

@@ -20,10 +20,10 @@ public class BreakBehavior : Behavior
         context.StopPropagation();
 
         // Remove child activity execution contexts.
-        var childActivityExecutionContexts = context.ActivityExecutionContext.GetChildren().ToList();
-        context.ActivityExecutionContext.WorkflowExecutionContext.RemoveActivityExecutionContexts(childActivityExecutionContexts);
+        var childActivityExecutionContexts = context.ReceiverActivityExecutionContext.GetChildren().ToList();
+        context.ReceiverActivityExecutionContext.WorkflowExecutionContext.RemoveActivityExecutionContexts(childActivityExecutionContexts);
         
         // Mark this activity as completed.
-        await context.ActivityExecutionContext.CompleteActivityAsync();
+        await context.ReceiverActivityExecutionContext.CompleteActivityAsync();
     }
 }

src/modules/Elsa.Workflows.Core/Behaviors/ExecutionLoggingBehavior.cs

@@ -0,0 +1,28 @@
+using System.Runtime.CompilerServices;
+using Elsa.Workflows.Core.Models;
+using Elsa.Workflows.Core.Services;
+using Elsa.Workflows.Core.Signals;
+
+namespace Elsa.Workflows.Core.Behaviors;
+
+/// <summary>
+/// Records Start and Completed entries of the owning activity. 
+/// </summary>
+public class ExecutionLoggingBehavior : Behavior
+{
+    public ExecutionLoggingBehavior(IActivity owner) : base(owner)
+    {
+        OnSignalReceived<ActivityCompleted>(OnActivityCompleted);
+    }
+
+    protected override void Execute(ActivityExecutionContext context)
+    {
+        context.AddExecutionLogEntry("Started");
+    }
+    
+    private void OnActivityCompleted(ActivityCompleted signal, SignalContext context)
+    {
+        if (context.IsSelf)
+            context.SenderActivityExecutionContext.AddExecutionLogEntry("Completed");
+    }
+}

src/modules/Elsa.Workflows.Core/Behaviors/ScheduledChildCallbackBehavior.cs

@@ -16,8 +16,8 @@ public class ScheduledChildCallbackBehavior : Behavior
 
     private async ValueTask OnActivityCompletedAsync(ActivityCompleted signal, SignalContext context)
     {
-        var activityExecutionContext = context.ActivityExecutionContext;
-        var childActivityExecutionContext = context.SourceActivityExecutionContext;
+        var activityExecutionContext = context.ReceiverActivityExecutionContext;
+        var childActivityExecutionContext = context.SenderActivityExecutionContext;
         var childActivity = childActivityExecutionContext.Activity;
         var callbackEntry = activityExecutionContext.WorkflowExecutionContext.PopCompletionCallback(activityExecutionContext, childActivity);
 

src/modules/Elsa.Workflows.Core/Extensions/ActivityExecutionContextExtensions.cs

@@ -13,9 +13,6 @@ public static class ActivityExecutionContextExtensions
     public static T GetInput<T>(this ActivityExecutionContext context) => context.GetInput<T>(typeof(T).Name);
     public static T GetInput<T>(this ActivityExecutionContext context, string key) => (T)context.Input[key];
 
-    public static WorkflowExecutionLogEntry AddExecutionLogEntry(this ActivityExecutionContext context, string eventName, string? message = default, object? payload = default) =>
-        context.AddExecutionLogEntry(eventName, message, default, payload);
-
     public static WorkflowExecutionLogEntry AddExecutionLogEntry(this ActivityExecutionContext context, string eventName, string? message = default, string? source = default, object? payload = default)
     {
         var activity = context.Activity;
@@ -78,7 +75,7 @@ public static class ActivityExecutionContextExtensions
 
         return input;
     }
-    
+
     public static async Task<T?> EvaluateAsync<T>(this ActivityExecutionContext context, Input<T> input)
     {
         var evaluator = context.GetRequiredService<IExpressionEvaluator>();
@@ -87,7 +84,7 @@ public static class ActivityExecutionContextExtensions
         locationReference.Set(context, value);
         return value;
     }
-    
+
     /// <summary>
     /// Returns a flattened list of the current context's ancestors.
     /// </summary>
@@ -107,7 +104,7 @@ public static class ActivityExecutionContextExtensions
     /// Returns a flattened list of the current context's immediate children.
     /// </summary>
     /// <returns></returns>
-    public static IEnumerable<ActivityExecutionContext> GetChildren(this ActivityExecutionContext context) => 
+    public static IEnumerable<ActivityExecutionContext> GetChildren(this ActivityExecutionContext context) =>
         context.WorkflowExecutionContext.ActivityExecutionContexts.Where(x => x.ParentActivityExecutionContext == context);
 
     /// <summary>
@@ -118,13 +115,13 @@ public static class ActivityExecutionContextExtensions
         // Detach child activity execution contexts.
         context.WorkflowExecutionContext.RemoveActivityExecutionContexts(context.GetChildren());
     }
-    
+
     /// <summary>
     /// Send a signal up the current branch.
     /// </summary>
     public static async ValueTask SignalAsync(this ActivityExecutionContext context, object signal)
     {
-        var ancestorContexts = context.GetAncestors();
+        var ancestorContexts = new[] { context }.Concat(context.GetAncestors());
 
         foreach (var ancestorContext in ancestorContexts)
         {
@@ -132,7 +129,7 @@ public static class ActivityExecutionContextExtensions
 
             if (ancestorContext.Activity is not ISignalHandler handler)
                 continue;
-            
+
             await handler.HandleSignalAsync(signal, signalContext);
 
             if (signalContext.StopPropagationRequested)

src/modules/Elsa.Workflows.Core/Models/Activity.cs

@@ -14,9 +14,9 @@ public abstract class Activity : IActivity, ISignalHandler
     protected Activity()
     {
         TypeName = ActivityTypeNameHelper.GenerateTypeName(GetType());
+        Behaviors.Add<ExecutionLoggingBehavior>(this);
         Behaviors.Add<ScheduledChildCallbackBehavior>(this);
         Behaviors.Add<AutoCompleteBehavior>(this);
-        Behaviors.Add<CreateCompletedLogRecord>(this);
     }
 
     protected Activity(string activityType) : this()

src/modules/Elsa.Workflows.Core/Pipelines/ActivityExecution/Components/ActivityInvokerMiddleware.cs

@@ -36,13 +36,12 @@ public class ActivityInvokerMiddleware : IActivityExecutionMiddleware
         var executeDelegate = workflowExecution.ExecuteDelegate ?? (ExecuteActivityDelegate)Delegate.CreateDelegate(typeof(ExecuteActivityDelegate), activity, methodInfo);
 
         // Record executing event.
-        LogExecutionRecord(context, WorkflowExecutionLogEventNames.Executing);
+        _logger.LogTrace("Executing activity {ActivityId}", activity.Id);
 
         await executeDelegate(context);
 
         // Record executed event.
-        var payload = context.JournalData.Any() ? context.JournalData : default;
-        LogExecutionRecord(context, WorkflowExecutionLogEventNames.Executed, payload: payload);
+        _logger.LogTrace("Executed activity {ActivityId}", activity.Id);
 
         // Reset execute delegate.
         workflowExecution.ExecuteDelegate = null;
@@ -57,6 +56,4 @@ public class ActivityInvokerMiddleware : IActivityExecutionMiddleware
             workflowExecution.RegisterBookmarks(context.Bookmarks);
         }
     }
-
-    private void LogExecutionRecord(ActivityExecutionContext context, string eventName, string? message = default, string? source = default, object? payload = default) => context.AddExecutionLogEntry(eventName, message, source, payload);
 }

src/modules/Elsa.Workflows.Core/Services/ISignalHandler.cs

@@ -9,15 +9,28 @@ public interface ISignalHandler
 
 public class SignalContext
 {
-    public SignalContext(ActivityExecutionContext activityExecutionContext, ActivityExecutionContext sourceActivityExecutionContext, CancellationToken cancellationToken)
+    public SignalContext(ActivityExecutionContext receiverActivityExecutionContext, ActivityExecutionContext senderActivityExecutionContext, CancellationToken cancellationToken)
     {
-        ActivityExecutionContext = activityExecutionContext;
-        SourceActivityExecutionContext = sourceActivityExecutionContext;
+        ReceiverActivityExecutionContext = receiverActivityExecutionContext;
+        SenderActivityExecutionContext = senderActivityExecutionContext;
         CancellationToken = cancellationToken;
     }
 
-    public ActivityExecutionContext ActivityExecutionContext { get; init; }
-    public ActivityExecutionContext SourceActivityExecutionContext { get; init; }
+    /// <summary>
+    /// The <see cref="ActivityExecutionContext"/> receiving the signal.
+    /// </summary>
+    public ActivityExecutionContext ReceiverActivityExecutionContext { get; init; }
+    
+    /// <summary>
+    /// The <see cref="ActivityExecutionContext"/> sending the signal.
+    /// </summary>
+    public ActivityExecutionContext SenderActivityExecutionContext { get; init; }
+    
+    /// <summary>
+    /// Returns true if the receiver is the same as the sender.
+    /// </summary>
+    public bool IsSelf => SenderActivityExecutionContext.Activity == ReceiverActivityExecutionContext.Activity;
+    
     public CancellationToken CancellationToken { get; init; }
     internal bool StopPropagationRequested { get; private set; }