Build a Web Application with Django and React

What's the Difference Between a Web App and a Website?

Websites have mostly static content and don't need much logic behind it. They play a presentational role, and interaction with them is limited. A marketing site is a good example: not much happens behind the scenes.

Web applications (web apps) have extensive logic that enables interaction. They are usually much more complex to develop, so they take much longer to create. YouTube is an example.

Progressive Web Apps (PWAs)

With web apps, you can also create PWAs, which work much like a regular mobile app. You can keep using the web app in your browser, or install it and use it offline.

In addition, platform restrictions do not apply to PWAs. You can use them on Android, iOS, Windows, macOS, Linux distributions, FreeBSD, you name it, and (most often) without any changes to the codebase.

One of the best libraries for creating web apps is React. It's an industry standard and the preferred option for most web developers. That covers the front-end. For the back-end, Django is a great option; it ships with many built-in features for convenience and development speed.

Django is a web framework and React is a UI library; each has its own part to play. Why are they such a good choice for designing web applications?

What is React?

React is a JS-based library for building UI. It is also used for developing the frontend of single-page applications (SPAs).

React is one of the most modern frameworks, leading alongside Angular, Vue, Svelte, and Solid. In 2021, according to the Stack Overflow Developer Survey, it took first place as the most popular web framework. More than 40% of all professional developers who participated in the survey chose it, and almost 70% of over 66,000 respondents said they love it.

What is Django?

Django is a Python web framework for the backend. Used by companies such as Instagram and Spotify, Django makes standard web development practices much easier.

In the same annual Stack Overflow survey, 55.3% of Django developers said they would continue to use it.

React App & a Django Backend

Let's take a closer look at a classic setup: a single-page React application in a Django project. Why do this at all?

What is a Single-Page Application (SPA)?

An SPA, or Single-Page Application, is a website or web app that, in the simplest terms, does not reload on navigation.

The SPA page is never refreshed. All code is retrieved with a single page load, or resources are added in response to the user's actions.

It is faster on subsequent navigations, but the initial load will always be longer than in a Multiple-Page App (MPA).

Why Is React a Great Choice?

React is one of the most popular technologies, with a fast-growing community and rapid development. Developers who use it say it makes app development easy and approachable and works well for advanced user interfaces.

It makes code reusable, so we can design small components and reuse them, even between projects.

React works really well for an SPA, where the whole site is a single page. From React's perspective, it is one application that supports routing, i.e. moving between pages, and the code is rendered on the user side.

What else makes React stand out?

• The component model of creating apps is easy to reason about.
• The components are reusable, just like custom widgets.
• The unidirectional data flow keeps the code predictable.

Virtual DOM is also one of the biggest advantages of React.

How Does the Virtual DOM Work?

A metaphor helps here.

Imagine you have a complex painting. Updating a small detail on the canvas would be a hassle, because you'd need to repaint the whole thing. That's roughly how traditional web pages work.

React uses a smarter approach called the Virtual DOM. Think of it as a blueprint of your actual web page. When you make a change in your React code, React first updates this blueprint. Then it compares the blueprint to the actual web page and updates only the parts that differ.

Here's how it works step by step:

1. Virtual DOM Update: When you change your React code, React updates the virtual DOM to reflect those changes.
2. Diffing: React then compares the new virtual DOM to the old one. It's like finding the differences between two drafts of your painting.
3. Minimal Updates: Instead of updating the entire web page, React only identifies the minimal changes needed (like a brushstroke here or there).
4. Real DOM Update: Finally, React applies those minimal changes to the actual web page.

This approach makes React fast, especially for complex web applications that change constantly. In the painting metaphor, React knows exactly which part of the canvas to touch up.

React is a library, not a framework, so we can choose exactly what we need in the web app. To save time, you can choose from many ready-made solutions. There are off-the-shelf UX and UI sets that we can easily customize, so we don't have to build such things from scratch.

React and SEO: A Modern Approach

React has many benefits for building dynamic user interfaces, but it wasn't always ideal for Search Engine Optimization (SEO). Traditionally, React rendered content on the client side (the user's browser) using JavaScript. Search engine crawlers rely primarily on HTML content to understand and rank web pages, so the mismatch between what React displayed and what crawlers saw could cause SEO issues.

React has changed a lot since then. Modern versions of React (18 and newer) and frameworks built on top of React (like Next.js and Gatsby) address SEO concerns with techniques like Server-Side Rendering (SSR). With SSR, the initial content of a web page is generated on the server, giving crawlers the HTML they need for indexing. This keeps your React application SEO-friendly.

Django: A Powerful Python Backend

Django is a popular and well-established Python web framework that gives developers a solid foundation for building web applications. Its strengths include:

• Fast Development: Django has tools like its built-in admin panel to quickly add functionality and manage data.
• Scalability: Django handles both small and large web applications well.
• Usable Templates: Django provides well-structured templates for building web pages, simplifying development. These templates can also be customized for unique needs.

Django is excellent on the back-end, but it isn't as capable as React at building complex user interfaces. Combining the two lets developers use the strengths of each:

• Improved User Experience: React makes it possible to build dynamic and interactive user interfaces.
• Strong Backend Foundation: Django is a secure and scalable foundation for managing data and application logic.

Communication Between React and Django

React and Django are connected through an API (Application Programming Interface). The API lets the React frontend communicate with the Django backend to retrieve and manipulate data.

Benefits of Using React and Django Together

• SEO-Friendly Applications: Modern React practices and frameworks make your application crawlable and indexable by search engines.
• Improved Performance: React updates only the parts of the interface that change, which makes interactions faster; with SSR, it can also shorten initial load times, which benefits both users and SEO.
• Clean and Maintainable Code: Both React and Django promote well-structured code, making it easier to maintain and update the application in the future.
• Flexibility: Django exposes the backend through an API, so the same backend can also serve mobile apps or other clients.

React and Django are a popular combination for building modern web applications. Together they are scalable and good for user experience, SEO, and maintainability. Developers get well-established, well-supported technologies for building fast, engaging web applications.

If you want to talk about creating a full-stack Django & React app, talk to us today.