Question

I am currently implementing an HTTP Handler that will take a POST of some XML data from some 3rd party, then will do some work with it. The processing that I will be doing with the XML has potential to take some time. Once I yank out the XML from the POST, there is no need to keep the connection open with the client while I process the data. As I don’t have any control of when the client will time out posting to me, I just want to grab the XML and let the connection go.

Is there any easy way to go about this? Using the Response.Close() isn’t correct, as it doesn’t close the connection properly. Response.End() exits my HTTP Handler all together. I could throw the processing into a background thread, but I heard that can be a little risky in ASP.NET as the AppDomain can be torn down which could kill my process in the middle.

Any thoughts would be much appreciated. Thanks for the help!

Answer 1

Thanks everyone for your input. The way I went about this, so others can ponder it as a solution:

The queuing would probably be the most “correct” means, but it would take some extra implementation that really is just over the top for what I am intending to do. Using the information from http://haacked.com/archive/2011/10/16/the-dangers-of-implementing-recurring-background-tasks-in-asp-net.aspx

First I create my processing class and spin that up in a background thread to do the work after I get the XML from the client. This releases the connection while my worker thread continues in the background.

I registered my processing class as an IRegisteredObject. I the implemented the Stop(bool immediate) method

    public void Stop(bool immediate)
    {
        if (!immediate && _working)
            return;//don't unregister yet, give it some time

        if(immediate && _working)
        {
            //TODO: Log this instance
        }
        HostingEnvironment.UnregisterObject(this);
    }

I set my _working variable to true when I am processing work, and unset it when done. If in the rare case I am processing work and stop gets called because the AppDomain is getting taken down, it will first just return without unregistering itself. This gives my process a bit more time to finish up. If when the method gets called the second time with the immediate flag set to true, it quickly logs the issue and then unregister itself.

This may not be the ultimate solution, but for my purposes, this will take care of alerting me when the very rare condition happens, as well as not holding up the client’s connection as I process the data.