Book Image

Django Design Patterns and Best Practices - Second Edition

By : Arun Ravindran
Book Image

Django Design Patterns and Best Practices - Second Edition

By: Arun Ravindran

Overview of this book

Building secure and maintainable web applications requires comprehensive knowledge. The second edition of this book not only sheds light on Django, but also encapsulates years of experience in the form of design patterns and best practices. Rather than sticking to GoF design patterns, the book looks at higher-level patterns. Using the latest version of Django and Python, you’ll learn about Channels and asyncio while building a solid conceptual background. The book compares design choices to help you make everyday decisions faster in a rapidly changing environment. You’ll first learn about various architectural patterns, many of which are used to build Django. You’ll start with building a fun superhero project by gathering the requirements, creating mockups, and setting up the project. Through project-guided examples, you’ll explore the Model, View, templates, workflows, and code reusability techniques. In addition to this, you’ll learn practical Python coding techniques in Django that’ll enable you to tackle problems related to complex topics such as legacy coding, data modeling, and code reusability. You’ll discover API design principles and best practices, and understand the need for asynchronous workflows. During this journey, you’ll study popular Python code testing techniques in Django, various web security threats and their countermeasures, and the monitoring and performance of your application.
Table of Contents (21 chapters)
Title Page
Copyright and Credits
PacktPub.com
Contributors
Preface
Index

Decorators


Before class-based views, decorators were the only way to change the behavior of function-based views. Being wrappers around a function, they cannot change the inner working of the view, and thus effectively treat them as black boxes.

decorator is a function that takes a function and returns the decorated function. Confused? There is some syntactic sugar to help you. Use the annotation notation @, as shown in the following login_required decorator example:

@login_required 
def simple_view(request): 
    return HttpResponse() 

The following code is exactly the same as the preceding:

def simple_view(request): 
    return HttpResponse() 
 
simple_view = login_required(simple_view) 

Since login_required wraps around the view, a wrapper function gets the control first. If the user was not logged-in, then it redirects to settings.LOGIN_URL. Otherwise, it executes simple_view as if it did not exist.

Decorators are less flexible than mixins. However, they are simpler. You can use both decorators...