Is it possible to override the format used when printing a Timestamp?

[arianf]

Is it possible to override the format used when doing JSON.pretty_generate for timestamps?

I've tried creating a refinement, but it's not working as expected.

module ActiveSupportExtensions
  refine ActiveSupport::TimeWithZone do
    def to_s(_format = :default)
      utc.iso8601(6)
    end
  end
end

class Export
  using ActiveSupportExtensions
  def export
    puts JSON.pretty_generate(User.last.as_json(only: [:created_at]))
  end
end

Export.new.export
# {
#   "created_at": "2022-04-05 14:36:07 -0700"
# }

While if I do a monkey patch, it does work

class ActiveSupport::TimeWithZone
  def to_s
    utc.iso8601(6)
  end
end

puts JSON.pretty_generate(User.last.as_json(only: [:created_at]))

# {
#   "created_at": "2022-04-05T21:36:07.878101Z"
# }

The only issue is that this overrides the entire applications TimeWithZone class, which is not something I want to do for obvious reasons.