Models fail to autoload in Rake files if config.threadsafe!

José,

unfortunately with config.threadsafe! enabled loading the environment dependency does not eager load models.

    $ bundle exec rails g model foo 
    ...
    rake db:migrate
    ...

    task :foo => :environment do
      Foo
    end

    $ bundle exec rake foo 
    rake aborted!
    uninitialized constant Foo
    /Users/stefan/tmp/threadsafe/Rakefile:9

I have noticed the same behaviour with migrations. If I want to use models from my app in migrations, I need to explicitly require the model and any of it's dependencies at the top of the migration. This is only necessary for environments where config.threadsafe! is set.

I know this strange, but, Isn't an expected behaviour ?

Copied from "http://guides.rubyonrails.org/configuring.html#configuring-action-c...:

config.action_controller.allow_concurrency should be set to true to allow concurrent (threadsafe) action processing. Set to false by default. You probably don’t want to call this one directly, though, because a series of other adjustments need to be made for threadsafe mode to work properly. Instead, you should simply call config.threadsafe! inside your production.rb file, which makes all the necessary adjustments.

WARNING:

Threadsafe operation is incompatible with the normal workings of development mode Rails. In particular, automatic dependency loading and class reloading are automatically disabled when you call config.threadsafe!.

The problem is actually that eager loading of application classes is disabled for rake tasks. From initializer.rb:

def load_application_classes

return if $rails_rake_task

...

end

I think this is intended to avoid catch-22s where you have a model class that borks if its database table doesn't exist, but you can't run the migration to create it because loading the Rails environment loads the class.

The issue is that the threadsafe! option still disables dependencies loading, so you can't refer to any of those classes implicitly if you actually want to.

I think the fix (perhaps instead of the existing guard in load_application_classes?) might be to ignore the threadsafe! and/or cache_classes options in rake tasks. After all, you're never accepting any controller requests within a rake runtime, so why would you care anyway? :)

This issue has been automatically marked as stale because it has not been commented on for at least three months.

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