OmniAuth provides a standardized interface for authenticating with various external providers. Once the user authenticates with the provider, it’s up to us developers to handle the callback and implement actual login and registration into the app. There is a wiki page laying out various scenarios that need to be handled if you want to support multiple providers, showing that it’s by no means a trivial task.

When Rodauth came out, I was excited to finally have a full-featured authentication framework that wasn’t tied to Rails, given that existing solutions required either Rails (Devise, Sorcery), or at least Active Record (Authlogic). Even though I mainly develop in Rails, I want other Ruby web frameworks to be viable alternatives, so I’m naturally drawn to generic solutions that everyone can use.

Multi-factor authentication or MFA (generalized two-factor authentication or 2FA) is a method of authentication where the user is required to provide two or more pieces of evidence (“factors”) in order to be granted access. Typically the user would first prove knowledge of something only they know (e.g. their password), and then prove posession of something only they own (e.g. another device). This provides an extra layer of security for the user’s account.

In this tutorial, we’ll show how to add fully functional authentication and account management functionality into a Rails app, using the Rodauth authentication framework. Rodauth has many advantages over the mainstream alternatives such as Devise, Sorcery, Clearance, and Authlogic, see my previous article for an introduction.

If you’re working with Rails, chances are your authentication layer is implemented using one of the popular authentication frameworks – Devise, Sorcery, Clearance, or Authlogic. These libraries provide complete authentication and account management functionality for Rails, giving you more time to focus on the core business logic of your product.