Where to start: Music Visualization, possibly from Spotify

Hi,

I am new to programming. I have basic knowledge of processing. I am trying to create a music visualizer using minim library. Ideally, I want to pull random music from Spotify ("HTTP requests for processing" library?) and visualize it.

Where to start? Is there any step by step tutorial for doing something similar?

Thanks!

P.S. I found this sketch on GitHub: https://github.com/alessandrocapra/ProcessingCubes/tree/master/cubes. But Spotify doesn't seem to work here. Also, I am not very clear on the steps with my basic knowledge.