Book Image

Python Programming Blueprints

By : Daniel Furtado, Marcus Pennington
Book Image

Python Programming Blueprints

By: Daniel Furtado, Marcus Pennington

Overview of this book

Python is a very powerful, high-level, object-oriented programming language. It's known for its simplicity and huge community support. Python Programming Blueprints will help you build useful, real-world applications using Python. In this book, we will cover some of the most common tasks that Python developers face on a daily basis, including performance optimization and making web applications more secure. We will familiarize ourselves with the associated software stack and master asynchronous features in Python. We will build a weather application using command-line parsing. We will then move on to create a Spotify remote control where we'll use OAuth and the Spotify Web API. The next project will cover reactive extensions by teaching you how to cast votes on Twitter the Python way. We will also focus on web development by using the famous Django framework to create an online game store. We will then create a web-based messenger using the new Nameko microservice framework. We will cover topics like authenticating users and, storing messages in Redis. By the end of the book, you will have gained hands-on experience in coding with Python.
Table of Contents (17 chapters)
Title Page
Copyright and Credits
Dedication
Contributors
Packt Upsell
Preface
Index

Creating the shopping cart model


It seems like now we have an application up and running, we can display our games, but there's a big issue here. Can you guess what? Okay, this question wasn't so hard, I gave the answer for that in the title of the section. Anyway, our users cannot buy the games—we need to implement a shopping cart so we can start making our users happy!

Now, there are many ways you can implement a shopping cart on an application, but we are going to do it by simply saving the cart items on the database instead of doing an implementation based in the user session.

The requirements for the shopping cart are as follows:

  • The users can add as many items they wish
  • The users should be able to change the items in the shopping cart; for example, they should be able to change the quantity of an item
  • Removal of items should be possible
  • There should be an option to empty the shopping cart
  • All the data should be validated
  • If the user owning that shopping cart is removed, the shopping cart and...