Shows optimistic concurrency at work for the Azure Tables implementation of JOliver's EventStore

gistfile1.cs

using System;
using EventStore;

namespace EventStoreConcurrencyTest
{
    class Program
    {
        static void Main(string[] args)
        {
            var eventStore1 = WireupEventStore();
            var eventStore2 = WireupEventStore();

            ConcurrencyException caughtException = null;
            Guid aggregateId = Guid.NewGuid();

            // A single commit to start with.
            using (var stream = eventStore1.CreateStream(aggregateId))
            {
                stream.Add(new EventMessage() { Body = new object() });
                stream.CommitChanges(Guid.NewGuid());
            }

            var stream1 = eventStore1.OpenStream(aggregateId, 0, int.MaxValue);
            var stream2 = eventStore2.OpenStream(aggregateId, 0, int.MaxValue);

            // Stream 1 commits first.
            stream1.Add(new EventMessage() { Body = new object() });
            stream1.CommitChanges(Guid.NewGuid());
            stream1.Dispose();

            // Stream 2 is writing 'concurrently'
            stream2.Add(new EventMessage() { Body = new object() });

            try
            {
                stream2.CommitChanges(Guid.NewGuid());
            }
            catch (ConcurrencyException ce)
            {
                // Result of a HTTP 409 Conflict response
                caughtException = ce;
            }

            if (caughtException != null)
            {
                Console.WriteLine("Caught ConcurrencyException. Optimistic Concurrency is working.");
            }
            else
            {
                // Does not happen :).
                Console.WriteLine("Did not catch an exception :(. Concurrency detection does not work.");
            }

            stream2.Dispose();
            eventStore1.Dispose();
            eventStore2.Dispose();
        }

        private static IStoreEvents WireupEventStore()
        {
            var es = Wireup.Init()
               .LogToOutputWindow()
               .UsingAzureTablesPersistence("Tables")
                    .InitializeStorageEngine()
               .UsingBinarySerialization()
               .Build();

            return es;
        }
    }
}