Simple time zone support

readme.md

Basic Usage

This is a super easy way to ensure that timestamps/datetimes etc render correctly according to the timezone that the object is in. In our usage we have a time_zone attribute on our models that stores the time zone in a format that we can find with active support. Example American Samoa, for more examples run bundle exec rake time:zones:all in your rails project.

We weren't aiming to display the datetime in a format relative to the user, but rather just display that the time was in X time zone

# lets assume we have an attribute called start_time
class Foo < ApplicationRecord
  include TimeZones
  
  time_zone_aware :start_time
end

foo = Foo.new(start_time: "2020-07-15 14:02:52", time_zone: "Pretoria")
foo.start_time.to_s # 2020-07-15 14:02:52 +0200
foo.time_zone = "Bogota"
foo.start_time.to_s # 2020-07-15 14:02:52 -0500

time_zones.rb

module TimeZones
  extend ActiveSupport::Concern

  included do
    def self.time_zone_aware(*attrs)
      attrs.each do |attribute|
        define_method(attribute) do
          return unless (value = super())
          value.in_time_zone(time_zone)
        end

        define_method("#{attribute}=") do |time|
          if time.is_a?(Hash)
            super(Time.find_zone(time_zone).local(*time.values_at(1, 2, 3, 4, 5, 6)))
          elsif time.respond_to?(:in_time_zone)
            super(time.in_time_zone(time_zone))
          else
            super(time)
          end
        end
      end
    end
  end
end

Maybe don't call super() twice?

-          return unless super()
-          super().in_time_zone(time_zone)
+          value = super()
+          return unless value
+          value.in_time_zone(time_zone)

Also, what if someone passes a String to the assignment method?