Intercept ARR caching with custom IIS module

Question

We use a custom IIS module to validate certain parameters of a client request. When we activate ARR caching on the same IIS server, the request is handled directly by ARR and not passed to the module, thus our checks are passed without validation. Changing the module order does not change the behavior. Is there a way to intercept ARR caching with a custom IIS module, so the request first gets to be handley by the module and then passed to ARR caching?

Answer 1

there is pipeline ordering, but it controls the order the modules are called for pipeline events. that is if two modules register for the same event handler, the order they are called in. you probably need to support an earlier event.

https://learn.microsoft.com/en-us/dotnet/api/system.web.httpapplication?redirectedfrom=MSDN&view=netframework-4.8#events