samples/workflow-external-invocation/CheckoutService/Activities/NotifyActivity.cs

using Dapr.Workflow;

namespace CheckoutServiceWorkflowSample.Activities
{
    public record Notification(string Message);

    public class NotifyActivity : WorkflowActivity<Notification, object?>
    {
        readonly ILogger _logger;

        public NotifyActivity(ILoggerFactory loggerFactory)
        {
            _logger = loggerFactory.CreateLogger<NotifyActivity>();
        }

        public override Task<object?> RunAsync(WorkflowActivityContext context, Notification notification)
        {
            _logger.LogInformation(notification.Message);
            return Task.FromResult<object?>(null);
        }
    }
}