Active Storage services default to private access, unless you specifically make them public.
By default, Active Storage assumes private access to services. This means generating signed, single-use URLs for blobs. If you’d rather make blobs publicly accessible, specify public: true in your app’s config/storage.yml
But sometimes apps need both private and public services. For example, User avatars and Account logos could be accessed directly, but Account reports need an authorization check with a redirect to a signed, single-use URL.
You can pass the service option to has_one_attached or has_many_attached, but what if you want to use local storage for running tests? Here’s a way to do that.