.NET: Shared State is not preserved in Subworkflows

[obayomy]

Scenario

1. Set a Shared State object from any executor in the main workflow.
2. Create a subworkflow, then try to read the Shared State object from any executor inside that workflow.
3. Reading the Shared State object returns null.

Example

class Program
{
    public static async Task Main(string[] args)
    {
        var text = "    Lorem ipsum dolor sit amet, consectetur adipiscing elit.  ";

        // Runs successfully
        await OneWorkflow(text, new TextReadExecutor(), new TextTrimExecutor(), new CharCountingExecutor());

        // Fails since shared state is not preserved across sub-workflow boundary
        await WithSubWorkflow(text, new TextReadExecutor(), new TextTrimExecutor(), new CharCountingExecutor());

    }

    private static async Task OneWorkflow(string text, TextReadExecutor textRead, TextTrimExecutor textTrim, CharCountingExecutor charCount)
    {
        Console.WriteLine("Running single workflow...");
        var workflow = new WorkflowBuilder(textRead)
            .AddEdge(textRead, textTrim)
            .AddEdge(textTrim, charCount)
            .WithOutputFrom(charCount)
            .Build();

        await using Run run = await InProcessExecution.RunAsync(workflow, text);
        foreach (WorkflowEvent evt in run.NewEvents)
        {
            if (evt is WorkflowOutputEvent outputEvent)
            {
                Console.WriteLine(outputEvent.Data);
            }
        }
    }

    private static async Task WithSubWorkflow(string text, TextReadExecutor textRead, TextTrimExecutor textTrim, CharCountingExecutor charCount)
    {
        Console.WriteLine("Running workflow with sub-workflow...");
        var subWorkflow = new WorkflowBuilder(textTrim)
            .Build();

        var subWorkflowStep = subWorkflow.BindAsExecutor("textTrim");

        var workflow = new WorkflowBuilder(textRead)
            .AddEdge(textRead, subWorkflowStep)
            .AddEdge(subWorkflowStep, charCount)
            .WithOutputFrom(charCount)
            .Build();

        await using Run run = await InProcessExecution.RunAsync(workflow, text);
        foreach (WorkflowEvent evt in run.NewEvents)
        {
            if (evt is WorkflowOutputEvent outputEvent)
            {
                Console.WriteLine(outputEvent.Data);
            }
            else if (evt is WorkflowErrorEvent failedEvent)
            {
                Console.WriteLine($"Workflow failed: {failedEvent.Data}");
            }
        }
    }
}

internal static class Constants
{
    public const string WordStateScope = "WordStateScope";

}

internal sealed class TextReadExecutor() : Executor<string, string>("TextReadExecutor")
{
    public override async ValueTask<string> HandleAsync(string word, IWorkflowContext context, CancellationToken cancellationToken = default)
    {
        string key = Guid.NewGuid().ToString();
        await context.QueueStateUpdateAsync(key, word, scopeName: Constants.WordStateScope, cancellationToken);

        return key;
    }
}

internal sealed class TextTrimExecutor() : Executor<string, string>("TextTrimExecutor")
{
    public override async ValueTask<string> HandleAsync(string key, IWorkflowContext context, CancellationToken cancellationToken = default)
    {
        var content = await context.ReadStateAsync<string>(key, scopeName: Constants.WordStateScope, cancellationToken)
            ?? throw new InvalidOperationException("Word state not found");

        var trimmed = content.Trim();

        await context.QueueStateUpdateAsync(key, trimmed, scopeName: Constants.WordStateScope, cancellationToken);

        return key;
    }
}

internal sealed class CharCountingExecutor() : Executor<string, int>("CharCountingExecutor")
{
    public override async ValueTask<int> HandleAsync(string message, IWorkflowContext context, CancellationToken cancellationToken = default)
    {
        var content = await context.ReadStateAsync<string>(message, scopeName: Constants.WordStateScope, cancellationToken);

        int charCount = content?.Length ?? 0;

        return charCount;
    }
}

• Version: 1.0.0-preview.251114.1