Promotions(Currenly you can't use it)

A small promotions library for your own small marketplace app.

Add this line to your application's Gemfile:

gem 'promotions'

And then execute:

bundle install

Or install it yourself as:

gem install promotions

A small example:

1. Let's assume our client is an online marketplace, here is a sample of some of the products available on our site:

   Product code	Name	Price
   001	Red Wine	£9.25
   002	Large Wheelie Bag	£45.00
   003	Tracksuit Bottoms	£19.95

   1. Our marketing team want to offer promotions as an incentive for our customers to purchase these items.

   2. If you spend over £60, then you get 10% of your purchase

   3. If you buy 2 or more Red Wine then the price drops to £8.50.

   4. Our check-out can scan items in any order, and because our promotions will change, it needs to be flexible regarding our promotional rules.

2. To implement these rules you need to use such an intefarface:

        # my_promotion.rb
        require 'promotions'
   
        class MyPromotions < Promotion
          item do 
            product_code Promotions::String
            name Promotions::String
            price Promotions::Money
          end
   
          # money.rb currency
          currency do 
            iso_code  "GBP"
            iso_numeric  "826"
            name "Pound sterling"
            symbol "£"
            subunit "Penny"
            subunit_to_unit 100
            decimal_mark "."
            thousands_separator ","
          end
   
          rules do 
            items.price.sum.gte 60.pounds do
              items.price.sum * 0.9
            end
   
            product_code.eq('002').& item.count.eq(2) do
              item.price = 8.50
            end
          end
        end

   Then in your Checkout class:

       class Checkout
         def initialize(promotional_rules)
           #...
           @promotional_rules = promotional_rules
   
           @promotional_rules.register_items([
             { product_code: '001', name: 'Red Wine', price: '9.25' },
             { product_code: '001', name: 'Large Wheelie Bag', price: '45.00' },
             { product_code: '001', name: 'Tracksuit Bottoms', price: '19.95' }
           ])
           #...
         end
   
         def scan(item)
           #...
           @promotional_rules.add_item(by_code: item)
           #...
         end
   
         def total
           #...
           @promotional_rules.total.in_text
           #...
         end
       end

3. The interface to our checkout looks like this (shown in Ruby):

   co = Checkout.new(MyPromotions.new)
   co.scan(item)
   co.scan(item)
   price = co.total

4. Your checkout system will work like this.

   Basket: 001,002,003

   Total price expected: £66.78

   Basket: 001,003,001

   Total price expected: £36.95

   Basket: 001,002,001,003

   Total price expected: £73.76

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/yanekx/promotions. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the Promotions project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.