Django provides several error handling techniques to handle errors in your web application.

REST framework will return a response with an appropriate status code and content-type. The body of the response will include any additional details regarding the nature of the error.

Learn how to handle errors in your Django web application using try-except blocks, built-in exceptions, error views, and custom error pages. Improve the user experience and avoid security issues with efficient error handling in Django.

The most common ways are:

1. Try-except block: You can use try-except blocks to catch exceptions and handle them in your views.

try:
    # code that may raise an exception
except Exception as e:
    # code to handle the exception

2. Django’s built-in exceptions: Django provides several built-in exceptions that you can raise and catch in your views. For example, you can raise django.core.exceptions.ValidationError if the data submitted by a user is invalid.

from django.core.exceptions import ValidationError

def my_view(request):
    # code to validate the data
    if invalid:
        raise ValidationError("Invalid data")

3. Django’s error views: Django provides several built-in error views that you can use to handle specific errors. For example, you can use django.views.defaults.page_not_found to handle 404 errors.

4. Custom error pages: You can create custom error pages for specific errors by creating templates for each error and mapping them to the corresponding error codes in your URL configuration.

# in your URL configuration
handler404 = 'myapp.views.custom_404_view'

# in your views
def custom_404_view(request, exception):
    return render(request, '404.html', status=404)

It’s important to handle errors in your web application to provide a smooth user experience and to avoid security issues.

A simple project to demonstrate Error Handling in Django:

1. Create a new Django project and app:

django-admin startproject errorhandling
cd errorhandling
python manage.py startapp errors

2. Create a custom error view for 404 errors:

# errors/views.py
from django.shortcuts import render

def custom_404(request, exception):
    return render(request, 'errors/404.html', status=404)

3. Create a template for the custom 404 error view:

# errors/templates/errors/404.html
<h1>404 Error</h1>
<p>Page not found</p>

4. Map the custom error view to the 404 error code in your URL configuration:

# errorhandling/urls.py
from django.urls import path, include
from errors import views

handler404 = 'errors.views.custom_404'

urlpatterns = [
    path('', include('errors.urls')),
]

5. Test the custom error view:

python manage.py runserver

Visit http://localhost:8000/non-existent-page/ in your browser. You should see the custom 404 error page that you created.

In this simple project, we demonstrated how to handle 404 errors in Django by creating a custom error view and mapping it to the 404 error code in the URL configuration. You can use the same approach to handle other errors such as 500 (internal server error), 403 (forbidden), and so on.