Django Framework

Why Django?

Django adopts a Model-View-Template (MVT) architectural pattern and emphasizes the Don’t Repeat Yourself (DRY) principle, making code reusable and modular. Its “batteries-included” nature provides tools and features for many common web development tasks, allowing developers to focus on the unique aspects of their applications instead of reinventing the wheel.

Key Features of Django

ORM (Object-Relational Mapping)

Django comes with a built-in ORM that allows developers to interact with their database, like querying, retrieving, and updating records, in Python. This means developers don’t need to write SQL code.

Admin Interface

Django provides a ready-to-use admin framework that can be autogenerated from the project models. It’s a powerful feature for managing the data in your application.

Middleware Support

Django uses middleware classes for request and response processing. It’s a light, low-level plugin system for globally altering Django’s input or output.

Security

Django helps developers avoid many common security mistakes by providing a secure way to handle user authentication and permissions, cross-site scripting, cross-site request forgery, SQL injection, and clickjacking.

Use Cases

Django can be used for a wide range of applications, from simple websites to complex, database-driven websites. It’s highly scalable and adaptable, with sites like Instagram and The Washington Post built using Django.

Django Rest Framework (DRF)

Django REST Framework is a powerful and flexible toolkit for building Web APIs that’s built on top of Django. It’s not a standalone framework; instead, it’s an additional layer you can add to a Django project to add API functionality. DRF makes it easy to build well-structured RESTful APIs by providing features like serialization for converting complex data types into JSON or XML formats, request parsing, authentication and permission policies, and browsable APIs.

While Django is a complete web framework for building traditional web applications, Django REST Framework is a toolkit built on Django for building Web APIs. They can be used together in the same project to serve HTML webpages and API endpoints.

Example

Here’s a simple Django view:

pythonCopy codefrom django.http import HttpResponse
from django.shortcuts import render

def hello_world(request):
    return HttpResponse("Hello, Django!")

In this example, hello_world is a Django view function that takes a web request and returns a web response. This particular response is just to return the text ‘Hello, Django!’, but normally, a view will do much more complex things, like querying the database and loading a template.

Here is a more advanced example in Django being used to create a model, a corresponding view, and a template.

Suppose we are building a blog application, and we want to have a view where we can see the details of a specific blog post. Here’s how we might do it:

Models.py

from django.db import models

class BlogPost(models.Model):
    title = models.CharField(max_length=200)
    content = models.TextField()
    pub_date = models.DateTimeField('date published')

    def __str__(self):
        return self.title

In this model, a blog post has a title, content, and a publication date.

Views.py

from django.shortcuts import render, get_object_or_404
from .models import BlogPost

def detail(request, post_id):
    post = get_object_or_404(BlogPost, pk=post_id)
    return render(request, 'blog/detail.html', {'post': post})

Here, we’ve created a view called detail that displays the details of a particular blog post. The post_id parameter is provided in the URL. If a BlogPost with the given ID exists, it is passed into the detail.html template. If it does not exist, a HTTP 404 error is raised.

Blog Page: blog/detail.html (Template)

<h1>{{ post.title }}</h1>
<p>{{ post.content }}</p>
<p>Published on: {{ post.pub_date }}</p>

Django has stood the test of time as one of the most popular Python web frameworks due to its robustness, scalability, and ease of use. It empowers developers to create complex database-driven websites and web applications rapidly. With its rich and ever-growing ecosystem, Django is an excellent choice for any web development project.