Signaling Workflow using CorrelationId or WorkflowId

program.cs

using System;
using System.Threading.Tasks;
using Elsa.Activities.Signaling.Services;
using Elsa.ActivityResults;
using Elsa.Builders;
using Elsa.Services;
using Elsa.Services.Models;
using Microsoft.Extensions.DependencyInjection;
using Elsa.Activities.Console;
using Elsa.Activities.ControlFlow;
using MediatR;
using Elsa.Events;
using System.Threading;
using System.Linq;

namespace Elsa.Samples.SignalingConsole
{
    /// <summary>
    /// Demonstrates a workflow with a While looping construct.
    /// </summary>
    internal static class Program
    {
        private static async Task Main()
        {
            // Create a service container with Elsa services.
            var services = new ServiceCollection()
                .AddElsa(options => options
                    .AddConsoleActivities()
                    .AddWorkflowsFrom<SignalReceiverWorkflow>()
                    .AddActivitiesFrom<SignalReceiverWorkflow>()
                    )
                

                .BuildServiceProvider();

            // Run startup actions (will index triggers such as SignalReceived from workflows).
            var startupRunner = services.GetRequiredService<IStartupRunner>();
            await startupRunner.StartupAsync();


            Console.WriteLine("Send UserWorkflow Signal");
            var signaler = services.GetRequiredService<ISignaler>();
            await signaler.TriggerSignalAsync("UserWorkflow");

            // Keep the application alive for the workflow scheduler to have enough time to resume the workflow. 
            Console.WriteLine("paste cor:{correlationid} or {instanceId} to continue");
            var instanceIdorCorrelationId = Console.ReadLine();
            if (instanceIdorCorrelationId.StartsWith("cor:"))
            {
                var correlationId = instanceIdorCorrelationId.Substring(4);
                var result = await signaler.TriggerSignalAsync("AdminSignal", correlationId: correlationId);

                Console.WriteLine($" found {result.ToArray().Length} using correlationId");
            }
            else
            {

                var result = await signaler.TriggerSignalAsync("AdminSignal",  workflowInstanceId: instanceIdorCorrelationId);
                Console.WriteLine($" found {result.ToArray().Length} using instanceId");

            }

            Console.ReadLine();
        }
    }

    public class RegisterWorkflow : IWorkflow
    {
        public void Build(IWorkflowBuilder builder)
        {
            builder
                .SignalReceived("UserWorkflow")
                .Then<StartRegisterActivity>()
                .WriteLine((ctx) => $"Signal received! -- Now Registering Activity and Waiting for admin signal with Instance Id {ctx.WorkflowInstance.Id}")
                .WriteLine((ctx) => $"Signal received! -- Now Registering Activity and Waiting for admin signal with Correlation Id {ctx.CorrelationId}")
                .SignalReceived("AdminSignal")
                .WriteLine(() => $"Signal From Admin Received")
                .Then<CompleteRegistrationAfterAdminActivity>()
                .WriteLine(() => $"End of Worflow")
                ;
        }
    }
    public class StartRegisterActivity : Elsa.Services.Activity
    {
        protected override IActivityExecutionResult OnExecute()
        {
            Console.WriteLine("doing something to start the registration process and wait for validation");
            return Done();

        }
    }
    public class CompleteRegistrationAfterAdminActivity : Elsa.Services.Activity
    {
        protected override IActivityExecutionResult OnExecute()
        {
            Console.WriteLine("doing something to validate the registration after Admin Signal");
            return Done();

        }
    }
}