How to Cause an HttpModule to be Invoked Before the First Request?

Question

I have several applications I am deploying to a .NET/IIS environment. For these applications I have registered an implementation of IHttpModule in the system.web/httpModules section of web.config. In my implementation of IHttpModule I have an Init() method which starts up some daemon threads and logs that the application has been started.

My problem is that Init() does not get called until the first HTTP request comes in. Is there a way to force the system to go ahead and execute my module immediately instead of waiting for the first HTTP request?

Answer 1

You should move your code to the Global.asax file in the Application_Start method :

protected void Application_Start(object sender, EventArgs e)
{
    //your initialization code
}

Update :
As noted in comments, this is not a solution to the problem as Application_Start is also called on first request.

So it seems that the only solution is to find a way to call a web page as soon as IIS is restarted.

Here are some suggestions from another website :

One tricky solution to this problem can be adding your website to search engines. Search engines crawl pages frequently. So, they will hit a page of your website resulting in Application_Start and thus the service will get up and running.

Another idea is to register your website to some traffic or availability monitoring services. There are lots of web services which keep an eye on your website and checks whether it is alive and the performance is satisfactory. All these services hit your web site pages and then collect the statistics. So, by registering in such services, you can guarantee your web application is alive all the time.

I'd go with the monitoring service solution, with services such as (I didn't try them) :
http://www.montastic.com/
http://www.siteuptime.com/

Answer 2

If you are on IIS7 you could use the IIS Application Warm up module to ensure your application is always running: http://learn.iis.net/page.aspx/688/using-the-iis-application-warm-up-module/

Check the application pool settings also, so it's not shutting down and restarting all the time whenever there is no activity.

Otherwise I'd recommend you create an NT Service and put your daemon threads there.