Authentication generator breaks apps with action_mailer/railtie disabled

[ramimassoud]

Steps to reproduce

1. Create a Rails 8 application with require "action_mailer/railtie" commented out in config/application.rb
2. Run bin/rails generate authentication
3. Boot the app in production mode or with config.eager_load = true. Also can enter PasswordsMailer in Rails console and try to evaluate the class.

Expected behavior

I believe all of the mailer templates should verify ActionMailer::Base is defined before generating mailer related files

rails/railties/lib/rails/generators/rails/authentication/authentication_generator.rb

Lines 24 to 29 in 57c2494

	template "app/mailers/passwords_mailer.rb"
	template "app/views/passwords_mailer/reset.html.erb"
	template "app/views/passwords_mailer/reset.text.erb"
	template "test/mailers/previews/passwords_mailer_preview.rb"

Actual behavior

PasswordsMailer is generated inheriting from ApplicationMailer, which does not exist.

System configuration

Rails version: Rails 8.0.1

Ruby version: ruby 3.3.6 (2024-11-05 revision 75015d4c1f) [x86_64-linux]

[zzak]

I cannot reproduce, how did you generate the app?

Unless you specified --skip-action-mailer you should have the correct files, and the require should be rails/all in app.rb.

[ramimassoud]

Thank you for the reminder! It's been a bit since I generated the app and forgot that would be helpful.

The exact flags I used were

rails new appname --skip-action-mailer --skip-action-mailbox --css=tailwind

I think the authentication generator should account for skipping action mailer and it's valid to want to have auth without sending emails

Thanks for the quick reply!

[zzak]

Do you want to try and open a PR?

Password reset feels like a must-have, so if you don't have actionmailer the generator should probably fail.

[ramimassoud]

I'm working on one. I just got the devcontainer working so I can run tests.

I was unsure what was the best path on a fix. In my case, I am working on a small prototype so I don't need to worry about emails or password reset just yet. I was planning on re-running the generator later when things were more "real" to pick up the reset email stuff.

Do you think it's reasonable to account for that case? Or, from your experience, would it be better overall to error and require actionmailer?

[zzak]

I think the generator can check if ActionMailer is loaded and if ApplicationMailer is defined, something like:

diff --git a/railties/lib/rails/generators/rails/authentication/authentication_generator.rb b/railties/lib/rails/generators/rails/authentication/a
uthentication_generator.rb
index f23ba7b2e1..b274b235cb 100644
--- a/railties/lib/rails/generators/rails/authentication/authentication_generator.rb
+++ b/railties/lib/rails/generators/rails/authentication/authentication_generator.rb
@@ -21,7 +21,9 @@ def create_authentication_files

         template "app/channels/application_cable/connection.rb" if defined?(ActionCable::Engine)

-        template "app/mailers/passwords_mailer.rb"
+        if has_action_mailer?
+          template "app/mailers/passwords_mailer.rb"
+        end

         template "app/views/passwords_mailer/reset.html.erb"
         template "app/views/passwords_mailer/reset.text.erb"
@@ -53,6 +55,13 @@ def add_migrations
       end

       hook_for :test_framework
+
+      private
+
+      def has_action_mailer?
+        (defined?(ActionMailer::Base) && defined?(ApplicationMailer)) ||
+          raise "Action Mailer is not defined in the application"
+      end

[JuanVqz]

Can I make this change?