There are many (old) clients available:
- https://github.com/tpitale/legato (active, supports API v3)
- https://github.com/activenetwork/gattica
- https://github.com/vigetlabs/garb
The Google Analytics API is at v3 (at time of writing).
This example uses Google's Ruby API client to access Analytics. Use https://github.com/google/google-api-ruby-client (Google supported).