Book Image

Web App Development Made Simple with Streamlit

By : Rosario Moscato
Book Image

Web App Development Made Simple with Streamlit

By: Rosario Moscato

Overview of this book

This book is a comprehensive guide to the Streamlit open-source Python library and simplifying the process of creating web applications. Through hands-on guidance and realistic examples, you’ll progress from crafting simple to sophisticated web applications from scratch. This book covers everything from understanding Streamlit's central principles, modules, basic features, and widgets to advanced skills such as dealing with databases, hashes, sessions, and multipages. Starting with fundamental concepts like operation systems virtualization, IDEs, development environments, widgets, scripting, and the anatomy of web apps, the initial chapters set the groundwork. You’ll then apply this knowledge to develop some real web apps, gradually advancing to more complex apps, incorporating features like natural language processing (NLP), computer vision, dashboards with interactive charts, file uploading, and much more. The book concludes by delving into the implementation of advanced skills and deployment techniques. By the end of this book, you’ll have transformed into a proficient developer, equipped with advanced skills for handling databases, implementing secure login processes, managing session states, creating multipage applications, and seamlessly deploying them on the cloud.
Table of Contents (23 chapters)
Free Chapter
1
Part 1: Getting Started with Streamlit
5
Part 2: Building a Basic Web App for Essential Streamlit Skills
10
Part 3: Developing Advanced Skills with a Covid-19 Detection Tool
15
Part 4: Advanced Techniques for Secure and Customizable Web Applications

Streamlit features and widgets

The very first step has been completed: Streamlit is up and running. What we need to do now is add text, widgets, elements, and more to make something beautiful that also works correctly.

To start populating our web app with nice and useful widgets, we need to write some Python code. The best way to do this is to put Sublime Text and our browser side by side, as shown in the following screenshot:

Figure 3.6: Sublime Text and a browser side by side

Figure 3.6: Sublime Text and a browser side by side

This kind of visualization is very convenient because we can immediately see any change we make to the code (in real time, as soon as we save our code changes), in our editor directly, in the browser by just selecting Always Rerun from the top-right menu of our web application:

Figure 3.7: Code changes and Always Rerun

Figure 3.7: Code changes and Always Rerun

So, let’s import Streamlit (with st as the alias) and start dealing with some text. We can write the following:

import...