Active Support’s CurrentAttributes: a really useful but hated Rails feature?

At Kaigi on Rails 2023, in Tokyo, Japan


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Some people dislike ActiveSupport::CurrentAttributes, but it’s undeniably very convenient. It allows you to safely use the much-loved global variables within requests—a truly handy feature. I want to discuss why it might be disliked, touching on precautions and past security flaws, such as an instance where information leakage occurred with a Puma and Rails combination.

While I’m not insisting that everyone should use ActiveSupport::CurrentAttributes, I want to convey that it’s a viable option for those times when it’s really necessary!


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