From 72b1b2bb40b689d213ee3ec71c650de4e8308218 Mon Sep 17 00:00:00 2001
From: Sipke Schoorstra <sipkeschoorstra@outlook.com>
Date: Wed, 17 Jan 2024 22:32:06 +0100
Subject: [PATCH] Add input parameter to ScheduleChildActivity signal

This update includes adding an optional input parameter to the ScheduleChildActivity signal's constructor in order to pass options to the child activity. The input parameter is used while scheduling activities in FlowFork.cs and Flowchart.cs activities. This enables clearer data transfer and scheduling in the system.
---
 .../Activities/Flowchart/Activities/FlowFork.cs  |  2 +-
 .../Activities/Flowchart/Activities/Flowchart.cs |  7 ++++++-
 .../Signals/ScheduleChildActivity.cs             | 14 ++++++++++++--
 .../Activities/FetchProducts.cs                  | 16 +++++-----------
 4 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/FlowFork.cs b/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/FlowFork.cs
index aa575b6fc..b3a8b9486 100644
--- a/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/FlowFork.cs
+++ b/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/FlowFork.cs
@@ -31,7 +31,7 @@ public class FlowFork : Activity
     /// <inheritdoc />
     protected override async ValueTask ExecuteAsync(ActivityExecutionContext context)
     {
-        var outcomes = Branches.GetOrDefault(context)?.ToArray() ?? new[] { "Done" };
+        var outcomes = Branches.GetOrDefault(context)?.ToArray() ?? ["Done"];
 
         await context.ScheduleOutcomesAsync(outcomes);
     }
diff --git a/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/Flowchart.cs b/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/Flowchart.cs
index cc0def319..7dd514ede 100644
--- a/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/Flowchart.cs
+++ b/src/modules/Elsa.Workflows.Core/Activities/Flowchart/Activities/Flowchart.cs
@@ -298,11 +298,16 @@ public class Flowchart : Container
             {
                 ExistingActivityExecutionContext = activityExecutionContext,
                 CompletionCallback = OnChildCompletedAsync,
+                Input = signal.Input
             });
         }
         else
         {
-            await flowchartContext.ScheduleActivityAsync(activity, OnChildCompletedAsync);
+            await flowchartContext.ScheduleActivityAsync(activity, new ScheduleWorkOptions
+            {
+                CompletionCallback = OnChildCompletedAsync,
+                Input = signal.Input
+            });
         }
     }
 }
\ No newline at end of file
diff --git a/src/modules/Elsa.Workflows.Core/Signals/ScheduleChildActivity.cs b/src/modules/Elsa.Workflows.Core/Signals/ScheduleChildActivity.cs
index e08714b4f..3b508defa 100644
--- a/src/modules/Elsa.Workflows.Core/Signals/ScheduleChildActivity.cs
+++ b/src/modules/Elsa.Workflows.Core/Signals/ScheduleChildActivity.cs
@@ -1,4 +1,5 @@
 using Elsa.Workflows.Contracts;
+using Elsa.Workflows.Options;
 
 namespace Elsa.Workflows.Signals;
 
@@ -11,23 +12,32 @@ public class ScheduleChildActivity
     /// Signaled when the scheduling of a child activity was requested.
     /// </summary>
     /// <param name="activity">The child activity to schedule.</param>
-    public ScheduleChildActivity(IActivity activity)
+    /// <param name="input">Input to pass to the child activity.</param>
+    public ScheduleChildActivity(IActivity activity, IDictionary<string, object>? input = default)
     {
         Activity = activity;
+        Input = input;
     }
 
     /// <summary>
     /// Signaled when the scheduling of a child activity was requested.
     /// </summary>
     /// <param name="activityExecutionContext">The child activity execution context to schedule.</param>
-    public ScheduleChildActivity(ActivityExecutionContext? activityExecutionContext)
+    /// <param name="input">The scheduling options.</param>
+    public ScheduleChildActivity(ActivityExecutionContext? activityExecutionContext, IDictionary<string, object>? input = default)
     {
         ActivityExecutionContext = activityExecutionContext;
+        Input = input;
     }
 
     /// <summary>The child activity to schedule.</summary>
     public IActivity? Activity { get; init; }
 
+    /// <summary>
+    /// Input to pass to the child activity.
+    /// </summary>
+    public IDictionary<string, object>? Input { get; set;}
+
     /// <summary>
     /// The child activity execution context to schedule.
     /// </summary>
diff --git a/src/samples/aspnet/Elsa.Samples.AspNet.BatchProcessing/Activities/FetchProducts.cs b/src/samples/aspnet/Elsa.Samples.AspNet.BatchProcessing/Activities/FetchProducts.cs
index f54dcb9fb..ead9d45a1 100644
--- a/src/samples/aspnet/Elsa.Samples.AspNet.BatchProcessing/Activities/FetchProducts.cs
+++ b/src/samples/aspnet/Elsa.Samples.AspNet.BatchProcessing/Activities/FetchProducts.cs
@@ -5,6 +5,7 @@ using Elsa.Workflows;
 using Elsa.Workflows.Attributes;
 using Elsa.Workflows.Models;
 using Elsa.Workflows.Options;
+using Elsa.Workflows.Signals;
 
 namespace Elsa.Samples.AspNet.BatchProcessing.Activities;
 
@@ -33,24 +34,17 @@ public class FetchProducts : CodeActivity<ICollection<Product>>
         var currentBatch = context.ActivityInput.TryGetValue(CurrentBathKey, out var currentBatchValue) ? (int)currentBatchValue : 0;
         var orders = GenerateProducts(count).Skip(currentBatch * batchSize).Take(batchSize).ToList();
 
+        Result.Set(context, orders);
+        await context.CompleteActivityAsync();
+        
         if (orders.Any())
         {
             currentBatch++;
             context.SetProperty(CurrentBathKey, currentBatch);
-            Result.Set(context, orders);
             
             // Schedule the next batch.
-            await context.ScheduleActivityAsync(this, new ScheduleWorkOptions
-            {
-                Input = new Dictionary<string, object>
-                {
-                    [CurrentBathKey] = currentBatch
-                }
-            });
+            await context.SendSignalAsync(new ScheduleChildActivity(this, new Dictionary<string, object> { [CurrentBathKey] = currentBatch }));
         }
-        
-        // Complete the activity.
-        await context.CompleteActivityAsync();
     }
 
     private IEnumerable<Product> GenerateProducts(int count)