The Ajax View JavaScript Instrumentation Proxy is the end result of the work from Microsoft Research. Essentially the tool is designed to act as a HTTP proxy focused on monitoring the performance and behavior of JavaScript applications within Internet Explorer 7, although Ajax View is not limited to just Microsoft's browser. The Redmond company only recently delivered a public version of Ajax View under an academic and non-commercial use license.

"Ajax View is an HTTP proxy that instruments JavaScript as it's served to the client based on a set of rules defined by plug-ins. The download includes a plug-in that contains a commented sample instrumentation policy. This design has a couple important effects. [First off] you can customize Ajax View to monitor exactly the JavaScript behavior you're looking for, whether it's about performance, or how people navigate through your site. And using Ajax View does not require modification of either the page source or the browser," explained John Hrvatin, Program Manager, Internet Explorer.

By using Ajax View you will be able to benefit from a server-side proxy (or web server plugin) "snook" in between the web server and the users' browser. In terms of actual functionality, Ajax View will automatically integrate dynamic instrumentation code in the JavaScript code belonging to a web application.

"You can use Ajax View to profile a site's JavaScript from your dev machine. Ajax View includes a few default instrumentation policies for basic profiling (timing based on before and after a function call in the caller, timing based on before and after a function call in the callee, etc.) but you can create a plug-in to track the JavaScript you're interested in," Hrvatin added.

Ajax View will permit the users to expand the proxy's dynamic instrumentation by integrating plug-ins and you will be able to see that such an item is provided with the download.