CabiShop

This is an excericse intended to manage promotions and discounts in virtual sotre. There is no inventory control, just basic product creation.

Installation

Elixir 1.5.1 or above is required.

If available in Hex, the package can be installed by adding cabishop to your list of dependencies in mix.exs:

def deps do
  [
    {:cabishop, "~> 0.1.0"}
  ]
end

If there is no need to use this app as library, you can just clone the source code, compile and start it from an iex session.

$ git clone https://github.com/gremly/cabishop.git

$ mix deps.get

$ mix test

$ iex -S mix

There is another posibility, instead of start it from iex, a release could be generated.

$ MIX_ENV=<desired_env> mix do clean, compile, release --env=<desired_env>

Usage

Products management

Before start the checkout process, it is needed to create some products in the store inventory.

Products are defined with the following structure:

prd =
  %CabiShop.Product{
    code: "PRODUCTCODE",
    name: "Product Name",
    price: 5.0,
    rules: %{payx: %{get: 2, pay: 1}}
  }

To save a product in the database, new_product/1 function from the main API can be used. Using the previous struct definition, the function usage looks like this:

> :ok = CabiShop.new_product(prd)

It is possible to get detailed information of a product using get_product/1.

> CabiShop.new_product("PRODUCTCODE")

Discount rules

There are two supported discount rules or promotions.

Discount for buying x quantity: It is known as bulk in the application. Defines a rule which applies a percentual discount to the price of a product, when the quantity to be bought is more than a defined minimum x.

The format to define this rule is the following Map: %{bulk: %{qty: 3, discount: 0.1}}
Promotion x-for-y: It is known as payx in the application. Defines the typical promotion of pay x quantity of a product and get y.

The format to define this rule is the following Map: %{payx: %{pay: 1, get: 2}}

Checkout process

As we are working with processes, to start selling products a checkout process should be started:

{:ok, co} = CabiShop.start_checkout()

If all products were created, they can be added one by one to the current checkout using scan_product/2:

CabiShop.scan_product(co, "PRODUCTCODE")

Finally, the calculation of the total price with discounts included is responsibility of the total/1 function:

CabiShop.total(co)

License

This work is free. Can be redistributed and/or modified under the terms of the MIT License.