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    copied!<p>I'd recommend you have a look at the <a href="https://github.com/mspnp/cqrs-journey-doc/" rel="nofollow">Microsoft Patterns &amp; Practices team's guidance on CQRS</a>. Although this is still work-in-progress they have given one solution to the issue you've raised. </p> <p>Their approach for commands requiring feedback is to submit the command asynchronously, redirect to another controller action and then poll the read model for the expected change or a time-out occurs. This is using the Post-Redirect-Get pattern which works better with the browser's forward and back navigation buttons, and gives the infrastructure more time to process the command before the MVC controller starts polling.</p> <p>Example code from the <a href="https://github.com/mspnp/cqrs-journey-code/blob/dev/source/Conference/Conference.Web.Public/Controllers/RegistrationController.cs" rel="nofollow">RegistrationController</a> using ASP.NET MVC 4 asynchronous controllers.</p> <pre><code>[HttpGet] [OutputCache(Duration = 0, NoStore = true)] public Task&lt;ActionResult&gt; SpecifyRegistrantAndPaymentDetails(Guid orderId, int orderVersion) { return this.WaitUntilOrderIsPriced(orderId, orderVersion) .ContinueWith&lt;ActionResult&gt;( ... ); } ... private Task&lt;PricedOrder&gt; WaitUntilOrderIsPriced(Guid orderId, int lastOrderVersion) { return TimerTaskFactory.StartNew&lt;PricedOrder&gt;( () =&gt; this.orderDao.FindPricedOrder(orderId), order =&gt; order != null &amp;&amp; order.OrderVersion &gt; lastOrderVersion, PricedOrderPollPeriodInMilliseconds, DateTime.Now.AddSeconds(PricedOrderWaitTimeoutInSeconds)); } </code></pre> <p>I'd probably use AJAX polling instead of having a blocked web request at the server.</p>
 

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