Create a search directive with AngularJS and Rails. You'll want to take a look at the related Rails TODO API Part 1 and Rails TODO API Part 2. This is not a Rails how-to, so some knowledge there is expected to get up and running.
This series will explore the basic fundamentals of React to get you started.
Protractor is an end-to-end testing framework for AngularJS applications. It allows you do drive the browser and test the expected state of your application's pages. This sort of functional testing is an essential component of any overall testing strategy.