Django Mock Interview | Interview Questions for Senior Django Developers

Summary

In this 2D Mark interview series, host Jose interviews software developer Andrew Espinoza for the role of an experienced Django developer. Andrew discusses his background in web and mobile development, highlighting projects like a 3D tourism website and a real-time delivery tracking system. The conversation delves into Django's architecture, middleware, caching, authentication, and ORM. Andrew also shares insights on Django's admin interface, mixins, and security practices, providing a comprehensive overview of Django's capabilities for developers.

Takeaways

• 😀 The interview is part of a 2D Mark interview series hosted by Jose, focusing on the role of an experienced Django developer.
• 🔍 The interviewee, Andrew Espinoza, is a software developer from Colombia with over five years of experience in web development and hybrid model development.
• 🛠 Andrew has worked with various technologies including JavaScript frameworks like Angular and React.js, Python frameworks like Django and Flask, and mobile development with Flutter.
• 🏆 Andrew has experience in fintech, healthcare, tourism, and other industries, developing robust and innovative solutions for various companies.
• 🌐 He has worked on projects such as a 3D website for a tourism claim using Three.js and a delivery company's software with real-time tracking capabilities.
• 🤔 The interview discusses middleware in Django, explaining its role in processing requests and responses within the application.
• 🏛 Django's architecture is based on the MVC pattern, with a template replacing the traditional controller role.
• 🔑 Django supports various caching methods, including memory caching, file system caching, and database caching, to improve performance.
• 🔒 Django offers built-in security features to protect against common threats like SQL injection, cross-site scripting, and cross-site request forgery.
• 🔄 Django's admin interface allows for quick development of a dashboard to manage application data, with customization options through plugins or templates.
• 🔄 Middleware is also used for authentication in Django, which can be easily integrated with other projects for authentication backends.

Q & A

What is the purpose of the interview with Andrew Espinoza?

The purpose of the interview is to discuss Andrew's experience and qualifications for the role of an experienced full-stack jungle developer.

What technologies has Andrew worked with in his career?

Andrew has worked with JavaScript, Angular, React.js, Python, Django, Flask, Flutter, and has experience in various industries including fintech, healthcare, tourism, and e-commerce.

Can you describe one of the projects Andrew mentioned during the interview?

One of the projects Andrew mentioned was a highly interactive 3D website for a tourism company that used Three.js to display a map of the region with attractions and points of interest using low poly models.

How did Andrew handle the data transfer from Python to Three.js in the 3D tourism project?

Data was fetched from the database by a Django script, which then called an API to download the models for display. The download included file compression, caching, and synchronous loading times to ensure a smooth user experience.

What is middleware in the context of Django?

Middleware in Django is a piece of logic that is executed every time a response is made to a request. It processes the request, performs necessary actions, and then serves the response.

Can you explain the Django architecture that Andrew discussed?

Django uses a modified version of the MVC (Model-View-Controller) pattern. Instead of a controller, it has a template. The model stores data, the view connects to the model and serves a template, which uses HTML, JavaScript, and Django's template engine to render data.

What are the different types of models in Django's model architecture?

Django has abstract base classes, multi-table models, and proxy models. Abstract base classes provide common information to child models, multi-table models allow each child to have their own database records, and proxy models allow cloning of a model and overriding its information.

How does caching work in Django?

Django offers various caching methods including memory caching, file system caching, and database caching. Memory caching is the fastest and most efficient, while file system caching stores cache files on the server, and database caching is useful for powerful databases with well-defined indexes.

What is the role of authentication in Django and can middleware be used for it?

Authentication in Django is used as a middleware. It manages user permissions and can be easily integrated into other projects. Django supports common hashing systems like bcrypt and sha256 for secure authentication.

Can Django be used as an API framework?

Yes, Django can be used as an API framework with the help of Django REST framework, which simplifies the development of APIs and provides powerful capabilities for API creation.

What are Django's supported databases and how can it be connected to non-supported databases like MongoDB?

Django supports major databases like PostgreSQL, MySQL, Oracle, and SQLite out of the box. For non-supported databases like MongoDB, third-party packages can be used. These packages need to be installed and configured in the settings.py file.

What are Django's field classes and what is their purpose?

Django's field classes are abstractions that define the structure of a database table, such as columns and data types. They are used in models to map database fields and ensure the correct data structure is used.

What is a mixin in the context of Django and the Django REST framework?

A mixin in Django is a type of inheritance that allows combining various pieces of code into one. In the context of the Django REST framework, mixins are used to quickly add functionality to views, such as CRUD operations.

What is the Django admin interface and how can it be customized?

The Django admin interface is a dashboard for managing data in applications. It can be customized by adding models and views to the admin.py file, using templates, or by adding JavaScript modules to customize functionality.

What are the best practices for security in Django?

Django has built-in protections against common threats, including SQL injection, cross-site scripting, and cross-site request forgery. Best practices also include enforcing SSL/HTTPS, session security, and proper input validation.

What is SQL injection and how can it be prevented in Django?

SQL injection is a vulnerability where an attacker can send SQL queries through an API request, potentially executing them on the server. Django prevents this by default through query escaping and sanitization, and developers can verify protection settings in the security section of the settings.py file.