Selenium on PhantomJS. In fact - a ready-made tool for web scraping. For example, the demo now opens a random page in Wikipedia and sends its header. (PhantomJS at the same time disguises itself as a ...

You should be able to put breakpoints in both your test code and your client code. Note that the debug option automatically adds the --remote-debugger-port=9000 and --remote-debugger-autorun=yes ...