The Sales module is the final one in the series of modules we will build in order to deliver a simple yet functional web shop application. We will do so by adding the cart and the checkout features on top of the catalog. The checkout itself will finally make use of the shipping and payment services defined throughout the previous chapters. The overall focus here will be on absolute basics, since the real shopping cart application would take a far more robust approach. However, understanding how to tie it all together in a simple way is the first step toward opening up a door for more robust web shop application implementations later on.
In this chapter, we will be covering the following topics of the Sales module:
Requirements
Dependencies
Implementation
Unit testing
Functional testing