Bumping to Rails 7.1 broke devise authentication, but not on development

Heading: Bumping to Rails 7.1 broke devise authentication, but not on development

Introduction:

Upgrading to Rails 7.1 from earlier versions might cause unexpected challenges, especially related to authentication. This article explores a common issue where Devise authentication breaks in production after the upgrade, while functioning normally in the development environment.

The Devise Authentication Issue:

1. Problem Statement: After upgrading to Rails 7.1, users encounter exceptions ("Can't verify CSRF token") when submitting login credentials in the production environment, while the development environment remains unaffected.
2. Root Cause: The issue often lies in the CSRF (Cross-Site Request Forgery) protection mechanism. Rails 7.1 introduced changes to the CSRF handling, leading to discrepancies between the production and development environments.
3. Debugging Approach: By adding logging statements to the code in ActionController::RequestForgeryProtection, it is possible to observe a difference in the result of the compare_with_global_token method. In production, this method returns false, triggering an exception, while in development, it returns true, allowing authentication to succeed.

Similar Issues and Solutions:

Similar issues have been reported by users not using Devise. These cases often involve CSRF-related problems after upgrading to Rails 7.1.

1. Passenger Upgrade: Some users found that upgrading Passenger (a web server interface for Ruby applications) resolved the CSRF issue in production. This suggests that compatibility issues between Rails 7.1 and older versions of Passenger might be a contributing factor.
2. Nginx and Passenger Configuration: Misconfigured Nginx and Passenger settings can also lead to CSRF token discrepancies. Ensuring proper configuration of these components is crucial for CSRF protection.

Resolution:

To resolve the issue, consider the following steps:

1. Upgrade Passenger: If you are using Passenger, ensure that you have the latest version installed. Upgrading Passenger often addresses the CSRF token mismatch issue in production.
2. Check Nginx and Passenger Configuration: Verify that Nginx and Passenger are configured correctly. Proper settings for these components are essential for CSRF protection.

Conclusion:

Upgrading to Rails 7.1 can introduce challenges related to CSRF authentication, particularly in production environments. By understanding the root cause of the issue and exploring potential solutions like upgrading Passenger or examining Nginx and Passenger configuration, developers can effectively resolve these problems and ensure secure authentication in their applications.