There are four types of pipeline processors in Themelia Pro: init, selector, override, and state. These are units of logic which run at a specific point in the Themelia pipeline. You can install as many of each as you want in your application.

Understanding pipeline processors is as simple as understanding the Themelia Pro pipeline. When someone accesses a Themelia Pro web site, the following occurs:

• Init processors run to setup or configure the request.
• If PassThroughHttpHandler.ForceUse is set, Themelia Pro stops for this request.
• If the request is a service alias, Themelia Pro runs service aliasing and stops for this request.
• If the request is a file alias, Themelia Pro runs file aliasing and stops for this request.
• The request is checked to see if the user is trying to access /Page_/ or /Sequence_/ without EnableDirectPageAccess being set. If so, NotFound catch-all and Themelia Pro runs file aliasing and stops for this request.
• Selection processors run to run custom endpoint selection.
• Themelia Pro endpoint selection runs.
• If no endpoint is selected, the catch-all runs.
• Override processors run to run custom logic to optionally replace the selected endpoint.
• State processors run to allow optional session state setup or reading.

From this you can see that Themelia Pro gives you multiple points of flexibility for endpoint handling.