Extending Your Shop

In the previous chapter, you learned how to integrate a payment gateway into your shop. You also learned how to generate CSV and PDF files.

In this chapter, you will add a coupon system to your shop and create a product recommendation engine.

This chapter will cover the following points:

• Creating a coupon system
• Applying coupons to the shopping cart
• Applying coupons to orders
• Creating coupons for Stripe Checkout
• Storing products that are usually bought together
• Building a product recommendation engine with Redis

The source code for this chapter can be found at https://github.com/PacktPublishing/Django-4-by-example/tree/main/Chapter10.

All the Python packages used in this chapter are included in the requirements.txt file in the source code for the chapter. You can follow the instructions to install each Python package in the following sections, or you can install all the requirements at once with the...

Creating a coupon system

Many online shops give out coupons to customers that can be redeemed for discounts on their purchases. An online coupon usually consists of a code that is given to users and is valid for a specific time frame.

You are going to create a coupon system for your shop. Your coupons will be valid for customers during a certain time frame. The coupons will not have any limitations in terms of the number of times they can be redeemed, and they will be applied to the total value of the shopping cart.

For this functionality, you will need to create a model to store the coupon code, a valid time frame, and the discount to apply.

Create a new application inside the myshop project using the following command:

python manage.py startapp coupons

Edit the settings.py file of myshop and add the application to the INSTALLED_APPS setting, as follows:

INSTALLED_APPS = [
    # ...
    'coupons.apps.CouponsConfig',
]

The new application is...

Building a recommendation engine

A recommendation engine is a system that predicts the preference or rating that a user would give to an item. The system selects relevant items for a user based on their behavior and the knowledge it has about them. Nowadays, recommendation systems are used in many online services. They help users by selecting the stuff they might be interested in from the vast amount of available data that is irrelevant to them. Offering good recommendations enhances user engagement. E-commerce sites also benefit from offering relevant product recommendations by increasing their average revenue per user.

You are going to create a simple, yet powerful, recommendation engine that suggests products that are usually bought together. You will suggest products based on historical sales, thus identifying products that are usually bought together. You are going to suggest complementary products in two different scenarios:

• Product detail page: You will display...

Additional resources

The following resources provide additional information related to the topics covered in this chapter:

• Source code for this chapter – https://github.com/PacktPublishing/Django-4-by-example/tree/main/Chapter10
• Discounts for Stripe Checkout – https://stripe.com/docs/payments/checkout/discounts
• The Redis ZUNIONSTORE command – https://redis.io/commands/zunionstore/

Summary

In this chapter, you created a coupon system using Django sessions and integrated it with Stripe. You also built a recommendation engine using Redis to recommend products that are usually purchased together.

The next chapter will give you an insight into the internationalization and localization of Django projects. You will learn how to translate code and manage translations with Rosetta. You will implement URLs for translations and build a language selector. You will also implement model translations using django-parler and you will validate localized form fields using django-localflavor.