tiny-shopping-cart

A tiny shopping cart implementation written in Ruby and Golang.

Installation

git clone https://github.com/cemeng/tiny-shopping-cart

Ruby version

Installation

cd tiny-shopping-cart/ruby
gem install bundle
bundle install

Run spec

rspec --format=documentation

Interacting with the shopping cart

Use Interactive Ruby (irb) which comes with ruby:

irb -r ./lib/shopping_cart.rb

Then you will have access to ShoppingCart object and interact with it.

Here is an example:

irb(main):001:0> cart = ShoppingCart.new(MobilePhonePricingRule)
=> #<ShoppingCart:0x007fab019525f0 @items=[], @bundled_items=[], @promo_codes=[], @pricing_rule=MobilePhonePricingRule>
irb(main):002:0> item1 = MobilePhonePricingRule.find_by_product_code('ult_small')
=> {:code=>"ult_small", :name=>"Unlimited 1GB", :price=>24.9}
irb(main):003:0> item2 = MobilePhonePricingRule.find_by_product_code('ult_small')
=> {:code=>"ult_small", :name=>"Unlimited 1GB", :price=>24.9}
irb(main):004:0> cart.add(item1)
=> nil
irb(main):005:0> cart.add(item2, 'I<3AMAYSIM')
=> ["I<3AMAYSIM"]
irb(main):006:0> cart.total
=> 44.82
irb(main):007:0> cart.items
=> [{:code=>"ult_small", :name=>"Unlimited 1GB", :price=>24.9}, {:code=>"ult_small", :name=>"Unlimited 1GB", :price=>24.9}]
irb(main):008:0> cart.clear

Golang version

The shopping cart code can be found at:

tiny-shopping-cart/golang/shopping_cart.go

The test is at:

tiny-shopping-cart/golang/shopping_cart_test.go

Please note that the golang code is written by someone with only few days experience of programming with Golang, so it is probably not as 'idiomatic' as it should be :)

Run test

cd golang
go test

Interacting with shopping cart

Modify the main function on shopping_cart.go to interact with the shopping cart.

Then run the code by:

cd golang
go run shopping_cart.go

However using The Go Playground is the easiest, I have created one here: https://play.golang.org/p/MiuscQzgZN

Below is an example of adding a product to the shopping cart and list the items and then prints out the total.

func main() {
	pricingRule := NewPricingRules()
	shoppingCart := NewShoppingCart(pricingRule)
	ultSmall, _ := pricingRule.findPricingByCode("ult_small")
	ultMedium, _ := pricingRule.findPricingByCode("ult_medium")

	shoppingCart.add(ultSmall)
	// shoppingCart.items() to list all items in shopping cart
	fmt.Println(shoppingCart.items())
	fmt.Println(shoppingCart.total())

	// empty shopping cart
	shoppingCart.clear()

	// add item and promo code
	shoppingCart.add(ultMedium, "I<3AMAYSIM")
	fmt.Println(shoppingCart.items())
	fmt.Println(shoppingCart.total())
}