Authentication plugin migration in CakePHP 5.0: testing integration without production credentials

Authentication plugin migration in CakePHP 5.0

The Authentication plugin was introduced in CakePHP 5.0 to replace the legacy AuthComponent. It offers adapters for Form, OAuth2, and JWT authentication, but the migration guides are sparse and the plugin is still considered experimental.

Testing integration without production credentials

Developers can leverage CakePHP’s TestCase class together with a TestUser fixture and the mockAuth helper to simulate login flows. This approach avoids the need for real user credentials while still exercising the authentication pipeline.

However, the plugin’s session handling differs from AuthComponent’s default behavior, and some adapters lack full feature parity. Additionally, AuthComponent remains in CakePHP 5 but is marked for removal in the upcoming CakePHP 6 release, leaving an unresolved decision about when to refactor existing codebases.

Given these constraints, the following questions remain unanswered:

• Does the mockAuth helper provide equivalent session handling for the Authentication plugin as it does for AuthComponent?
• What are the practical differences in user state persistence between the two implementations when using the Form adapter?
• Should projects migrate to the new plugin now or postpone until a clearer deprecation timeline for AuthComponent is established in CakePHP 6?