How do I pull Google analytics data into a rails app for multiple users who each have their own site?

Question

I have a rails app where users can create projects. For each project, I want to allow my users to associate a google account with the project and then pull in relevant google analytics data (i.e. page views, organic traffic, paid traffic) to be presented as part of this project dashboard. What would be the best way to pull in this google data for multiple users, each who will add their own unique google analytics account for a given project?

I've seen some references to Garb as the standard Ruby library to access the google API, but I'm not able to figure out how to use that in my rails app to pull in the relevant data I'm looking for.

Is Garb still a relevant solution for Ruby/Rails? Are there any good example applications that use Garb to pull in Google data? Sorry for the open ended nature of this question, but I've been researching this one for a while with little success. Thanks for your help!