The Rails 4 Way (2014)
Chapter 1. Rails Environments and Configuration
Chapter 3. REST, Resources, and Rails
Chapter 4. Working with Controllers
Chapter 5. Working with Active Record
Chapter 6. Active Record Migrations
Chapter 7. Active Record Associations
Chapter 9. Advanced Active Record
Chapter 13. Session Management
Chapter 14. Authentication and Authorization
Chapter 17. Caching and Performance
Chapter 18. Background Processing