Top Django Interview Questions

Top 25 Django Interview Questions

Top 25 Django Interview Questions

A list of top frequently asked Django interview questions and answers are given below.

1) Explain Django.

Django is a Python-based web application framework that is free and open source. It’s a server-side web framework for building secure and maintainable websites quickly.

2) What does Django mean?

Django is named after Django Reinhardt, a gypsy jazz guitarist who was one of the best guitarists of all time from the 1930s until the early 1950s.

3) Which architectural pattern does Django follow?

Django follows Model-View-Template (MVT) architectural pattern.

See the following graph that shows the MVT based control flow. Learn more about Django MVT pattern here.

Here, a user requests for a resource to the Django, Django works as a controller and check to the available resource in URL.

If URL maps, a view is called that interact with model and template, it renders a template.

Django responds back to the user and sends a template as a response.

4) Explain Django architecture.

Django follows MVT (Model View Template) pattern. It is slightly different from MVC.

Model: It is the data access layer. It contains everything about the data, i.e., how to access it, how to validate it, its behaviors and the relationships between the data.

Let’s see an example. We are creating a model Employee who has two fields first_name and last_name.

from django.db import models class Employee(models.Model): first_name = models.CharField(max_length=30) last_name = models.CharField(max_length=30)

View: It is the business logic layer. This layer contains the logic that accesses the model and defers to the appropriate template. It is like a bridge between the model and the template.

import datetime # Create your views here. from django.http import HttpResponse def index(request): now = datetime.datetime.now() html = "<html><body><h3>Now time is %s.</h3></body></html>" % now return HttpResponse(html) # rendering the template in HttpResponse
Code language: HTML, XML (xml)

Template: It is a presentation layer. This layer contains presentation-related decisions, i.e., how something should be displayed on a Web page or other type of document.

To configure the template system, we have to provide some entries in settings.py file.

TEMPLATES = [ { 'BACKEND': 'django.template.backends.django.DjangoTemplates', 'DIRS': [os.path.join(BASE_DIR,'templates')], 'APP_DIRS': True, 'OPTIONS': { 'context_processors': [ 'django.template.context_processors.debug', 'django.template.context_processors.request', 'django.contrib.auth.context_processors.auth', 'django.contrib.messages.context_processors.messages', ], }, }, ]
Code language: PHP (php)

5) Is Django a high-level web framework or low-level framework?

Django is a high-level Python web framework that focuses on speedy development and a clean, realistic design pattern.

6) How would you pronounce Django?

Django is pronounced JANG-oh. Here D is silent.

7) How does Django work?

Django can be broken into many components:

Models.py file: This file establishes your data model by turning your single line of code into entire database tables and including a content management section.

Urls.py file: It captures URL patterns for processing using a regular expression.

Views.py file: It is the most important aspect of Django. The real procedure takes place in plain sight.

When a visitor arrives at a Django page, Django first validates the URL pattern you’ve set up and uses that information to retrieve the view. Following that, the view processes the request, maybe accessing your database, and provides the requested data to a template.

The template then produces the data in the layout you specified and displays the page.

8) Which foundation manages the Django web framework?

The Django web framework is administered and maintained by the Django Software Foundation, a non-profit organization (DSF). The Django Web framework is promoted, supported, and advanced as the foundation’s primary aim.

9) Is Django stable?

Yes, Django is a very stable framework. Django has been used by many firms for many years, including Disqus, Instagram, Pinterest, and Mozilla.

10) What are the features available in Django web framework?

Django web framework has the following features:

  • Admin Interface (CRUD)
  • Fantastic Documentation
  • Form handling
  • Templating
  • A Session, user management, role-based permissions
  • Object-relational mapping (ORM)
  • Internationalization
  • Testing Framework

11) Explain the advantages of Django?

Django’s Benefits:

  • Django is a Python’s framework which is easy to learn.
  • It is scalable.
  • It is versatile.
  • It is fast to write.
  • No loopholes in design.
  • It is secure.
  • It is clear and readable.
  • It is versatile.

12) What are the disadvantages of Django?

The following is a list of Django’s drawbacks:

  • Django’ modules are bulky.
  • Components are deployed together.
  • It is completely based on Django ORM.
  • You must know the full system to work with it.

13) What are the inheritance styles in Django?

There are three possible inheritance styles in Django:

1) Abstract base classes: This style is used when you only want parent’s class to hold information that you don’t want to type out for each child model.

2) Multi-table Inheritance: This style is used if you are sub-classing an existing model and need each model to have its database table.

3) Proxy models: This style is used, if you only want to modify the Python level behavior of the model, without changing the model’s fields.

14) Is Django a content management system (CMS)?

Django is not a content management system. Instead, it is a programming tool and a Web framework that allows you to create websites.

15) How can you set up static files in Django?

There are three main things required to set up static files in Django:

1) Set STATIC_ROOT in settings.py

2) run manage.py collect static

3) set up a Static Files entry on the PythonAnywhere web tab

16) What is some typical usage of middlewares in Django?

Some usage of middlewares in Django is:

  • Session management,
  • Use authentication
  • Cross-site request forgery protection
  • Content Gzipping

17) What does of Django field class types do?

The Django field class types specify:

  • The database column type.
  • The default HTML widget to avail while rendering a form field.
  • The minimal validation requirements used in Django admin.
  • Automatic generated forms.

Django-admin.py: It is a Django’s command line utility for administrative tasks.

Manage.py: It is an automatically created file in each Django project. It is a thin wrapper around the Django-admin.py. It has the following usage:

  • It puts your project’s package on sys.path.
  • It sets the DJANGO_SETTING_MODULE environment variable to points to your project’s setting.py file.

19) What are the signals in Django?

Signals are pieces of code which contain information about what is happening. A dispatcher is used to sending the signals and listen for those signals.

20) What are the two important parameters in signals?

Two important parameters in signals are:

  • Receiver: It specifies the callback function which connected to the signal.
  • Sender: It specifies a particular sender from where a signal is received.

21) How to handle URLs in Django?

To handle URL, django.urls module is used by the Django framework.

Let’s open the file urls.py of the project and see the what it looks like:

// urls.py

from django.contrib import admin from django.urls import path urlpatterns = [ path('admin/', admin.site.urls), ]
Code language: JavaScript (javascript)

See, Django already has mentioned a URL here for the admin. The path function takes the first argument as a route of string or regex type.

The view argument is a view function which is used to return a response (template) to the user.

The django.urls module contains various functions, path(route,view,kwargs,name) is one of those which is used to map the URL and call the specified view.

22) What is Django Exception?

An exception is an abnormal event that leads to program failure. To deal with this situation, Django uses its exception classes and supports all core Python exceptions as well. Django core exceptions classes are defined in django.core.exceptions module.

23) What are the different types of Django Exception Classes?

The django.core.exceptions module contains the following classes

ExceptionDescription
AppRegistryNotReadyIt is raised when attempting to use models before the app loading process.
ObjectDoesNotExistThe base class for DoesNotExist exceptions.
EmptyResultSetIf a query does not return any result, this exception is raised.
FieldDoesNotExistIt raises when the requested field does not exist.
MultipleObjectsReturnedThis exception is raised by a query if only one object is expected, but multiple objects are returned.
SuspiciousOperationThis exception is raised when a user has performed an operation that should be considered suspicious from a security perspective.
PermissionDeniedIt is raised when a user does not have permission to perform the action requested.
ViewDoesNotExistIt is raised by django.urls when a requested view does not exist.
MiddlewareNotUsedIt is raised when a middleware is not used in the server configuration.
ImproperlyConfiguredThe ImproperlyConfigured exception is raised when Django is somehow improperly configured.
FieldErrorIt is raised when there is a problem with a model field.
ValidationErrorIt is raised when data validation fails to form or model field validation.

24) What is Django Session?

During the interaction with the web application, a session is a technique for storing information on the server side. Sessions are stored in the database by default, however they can optionally be saved to a file or cache.

25) What is the role of Cookie in Django?

A cookie is a little bit of data that is stored in the browser of the client. It is used to permanently save user data in a file (or for the specified time). When a cookie reaches its expiration date and time, it is automatically removed. Django comes with built-in methods.

The set_cookie() method is used to set a cookie and get() method is used to get the cookie.

The request.COOKIES[‘key’] array can also be used to get cookie values.

from django.shortcuts import render from django.http import HttpResponse def setcookie(request): response = HttpResponse("Cookie Set") response.set_cookie('java-tutorial', 'javatpoint.com') return response def getcookie(request): tutorial = request.COOKIES['java-tutorial'] return HttpResponse("java tutorials @: "+ tutorial); <a href="https://www.javatpoint.com/django-interview-questions-and-answers#"></a>
Code language: JavaScript (javascript)

%d bloggers like this: