Web-based applications (web apps) offer multi-level advantages. First, users can enjoy a unified experience across platforms. Second, since an installation process is not required, users can enjoy a simpler workflow. Lastly, from the perspective of developers, the development cycle can be simplified as less platform-specific code has to be maintained. Given these advantages, more and more applications are being developed online.

Owing to the popularity and flexibility of Python, it makes sense for web developers to use Python-based web frameworks such as Django and Flask to develop web applications. In fact, Django and Flask ranked 6th and 13th out of 175 respectively in terms of popularity, according to http://hotframeworks.com/. These frameworks are batteries included. From user authentication, user administration, and content management to API design, these frameworks have got them all covered. The code base is closely reviewed by the open source community such that sites that were developed using these frameworks are protected against common attacks, such as SQL injection, cross-site request forgery, and cross-site scripting.

In this chapter, we are going to learn how to develop a simple site that displays the price of Bitcoin. Examples based on Django  will be covered. We will use Docker 18.03.0-ce, and Django 2.0.4 for demonstration. Let's begin by going through the steps of initializing a Docker-based development environment.