I would suggest using this gem:
https://github.com/oshuma/app_config
Given this YAML file:
---
admin_email: 'admin@example.com'
api_name: 'Supr Webz 2.0'
api_key: 'SUPERAWESOMESERVICE'
Use it like so:
AppConfig.setup!(yaml: '/path/to/app_config.yml')
# Later on...
AppConfig.admin_email # => 'admin@example.com'
AppConfig.api_name # => 'Supr Webz 2.0'
AppConfig.api_key # => 'SUPERAWESOMESERVICE'
This could easily be added to your spec_helper