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Let me prefix first that there are already two questions from Stack Overflow with accepted answers that async action filters are not supported:

Async action filter in MVC 4
Calling Async Methods in Action Filters in MVC 5

So, I'm looking for a 'work-around'. This is what I currently do in my WebApi application: 

public class MessageLoggingHandler : DelegatingHandler
{

    protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
    {
        await LogRequestInfo(request);
        var response = await base.SendAsync(request, cancellationToken);
        await LogResponseInfo(response);
        return response;
    }

What I am trying to achieve is to log the request and log the response as a cross cutting concern. How can I do this in MVC? Is it even possible? I see two posts with a possible solution... has anyone used it? Does it work? Should I even go down this path? Are there alternatives? I'm really hesitant to adopt either approach for fear of breaking something in our application.

1) Implement a custom AsyncControllerActionInvoker
http://ayende.com/blog/163170/building-async-unit-of-work-with-mvc-4

2) Create and Async Controller Base Class, uses the "ParallelExtensionsExtras" library (whatever that is), and overrides some of the BeginExecute, EndExecute methods.
Perform Async operation asp.net mvc outside of the action

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Raymond
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    ASP.NET vNext *will* support async filters on its version of MVC. So, another option is to just log synchronously for now (inefficient, but it works), and then upgrade to a proper async filter when ASP.NET vNext comes out. – Stephen Cleary Sep 12 '14 at 23:24
  • When you say do it synchronously, do you mean that I have to change my controller methods to be synchronous too? All our action methods are async at the moment, and I don't want to be telling the team to re-write all the code to make it synchronous again with threads to call the async code. – Raymond Sep 15 '14 at 23:51
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    No, you can just make the `Log*Info` methods called from the filter synchronous; the controller methods can stay asynchronous. – Stephen Cleary Sep 16 '14 at 00:01
  • I've recently [published a library](https://www.nuget.org/packages/Hydrogen.Extensions.Mvc5.Async) that adds proper support for async filters (heavily based on code in from [ASP.NET MVC Core](https://github.com/aspnet/Mvc)). Source is also available here: https://github.com/jdaigle/Hydrogen.Extensions.Mvc5. – Joseph Daigle Mar 21 '17 at 02:36

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