Workaround for https://github.com/aspnet/KestrelHttpServer/issues/103

KestrelWorkaround.cs

using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNet.Builder;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Mvc.Internal;

namespace Samples.Pages
{
    // TODO - check to see if this is still needed by Kestrel
    public class KestrelWorkaround
    {
        readonly RequestDelegate next;

        public KestrelWorkaround(RequestDelegate next)
        {
            this.next = next;
        }

        public async Task Invoke(HttpContext ctx)
        {
            var resp = ctx.Response;

            // Replace the body stream with a fake one
            var realBodyStream = resp.Body;
            var fakeBody = new MemoryStream();
            resp.Body = new NonDisposableStream(fakeBody);

            await next(ctx);

            // Thanks to NonDisposableStream, we can just move the position on our MemoryStream
            fakeBody.Position = 0;

            // Swap the real body stream back in
            resp.Body = realBodyStream;

            await fakeBody.CopyToAsync(resp.Body);
        }
    }
}