A while back, I built a Python library for the Seeed Studio Raspberry Pi Relay Controller board; I wrote about that project on this site. As I worked to add some new features to the library, I realized that I needed an easy way to test the different components of the library. I decided to build a web application for the Raspberry Pi that provided an interface for each of the library's functions. I built the application using Flask, an easy to use micro framework for Python; you can find the project's complete source code at https://github.com/johnwargo/Raspberry-Pi-Relay-Controller-Seeed.
When you install the application and configure the Pi to execute the project's server task at startup, you can point your Pi browser to http://127.0.0.1:5000 and you'll see the following interface: