Devise VS Doorkeeper

Since Rails 7, there's more and more tooling that enables us, developers, to roll our own authentication. Devise is great and has been an amazing companion over the years. It also has this neat little feature - an authenticated route constraint which "hides" certain routes from people that are not signed in.

[changelog] https://github.com/heartcombo/devise/blob/main/CHANGELOG.md [upgrade guide] https://github.com/heartcombo/devise/wiki/How-To:-Upgrade-to-Devise-4.9.0-%5BHotwire-Turbo-integration%5D

As much as this article is about user authorization, there's something important we need to cover: user authentication. Without it, any authorization policies we try to define later on will be useless. But there is no need to write authentication from scratch. Let's use Devise.

With around 50 new gems released daily, it is common to use trending libraries for managing everyday tasks. You probably use Devise for authentication, Cancan for authorization, Kaminari for pagination, or run tests with Rspec.

Devise is an authentication library built on top of Warden, a Rack-based authentication framework.

devise: An authentication library designed for Rails

I used Devise, this is a Ruby on Rails app

In this article, we will explore how to implement authentication in a Rails 7 application using the popular devise gem. Authentication is a crucial aspect of web development, allowing users to securely access and interact with your application. By following this step-by-step guide, you will learn how to set up devise, configure authentication routes, create user models, and enhance your application with authentication features.

The doorkeeper gem.

Take a look at doorkeeper.

Disclosure: I work for FusionAuth.

Depends on what you are looking for.

If you want a standalone auth server, you can use FusionAuth in docker/docker-compose: https://fusionauth.io/docs/v1/tech/installation-guide/docker

You can also package up a library; most major languages have one or more OAuth/OIDC libraries: https://github.com/doorkeeper-gem/doorkeeper for Ruby, https://spring.io/projects/spring-security for Spring/Java, https://oauth2.thephpleague.com/ for PHP, https://pypi.org/project/oauthlib/ for Python.

https://oauth.net/code/ has a further selection of libraries in a variety of languages.

Are there any code examples to implement the PKCE flow in Doorkeeper? I am a bit confused on how to implement it here: https://github.com/doorkeeper-gem/doorkeeper/wiki/Using-PKCE-flow

For authorization we use Doorkeeper gem with PKCE flow.

One thing that is missing from this list is open source language specific libraries. Projects such as https://oauthlib.readthedocs.io/en/latest/oauth2/server.html and https://github.com/doorkeeper-gem/doorkeeper

Depending on your use case, for example if you only have one application, you might be better off running something embedded in your app, or independent but using the same runtime/deployment environment. Then, when you are ready to add another app or integration, you should be able to introduce a standalone auth system more easily if appropriate (because all your auth interactions should be relatively standardized). I'm a big fan of standalone auth systems as a way to simplify access control and give a single view of a user/customer, but you can also succeed using open source embedded libraries.

When the moment comes to introduce a standalone system, you should consider a few dimensions (this list pulled from a previous comment of mine: https://news.ycombinator.com/item?id=26360048 ):

   * open source or not