Web App Development Made Simple with Streamlit: A web developer's guide to effortless web app development, deployment, and scalability

Web App Development Made Simple with Streamlit

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This book was in progress for a long time, and I would like to thank all my e-students for supporting me and pushing me to turn video lessons into pages. I would also to thank my kids, Liv and Giu, for motivating me to be a role model, and my parents for inspiring me to do great things and keep moving forward toward a noble target, come what may!

- Rosario Moscato

Contributors

About the author

Rosario Moscato has a master’s degree in electronic engineering (Federico II University, Naples) as well as a master’s degree in internet software design (CEFRIEL, Milan). He also has a diploma in apologetics (Pontifical Athenaeum Regina Apostolorum, Rome) and a master’s degree in science and faith (Pontifical Athenaeum Regina Apostolorum, Rome). Rosario has gained about 25 years of experience, always focusing his attention on the development and fine-tuning of the most innovative technologies in various international companies in Europe and Asia, covering various highly technical, commercial, and business development roles.

In recent years, his interest has focused exclusively on artificial intelligence and data science, pursuing, on the one hand, the goal of enhancing and making every business extremely competitive by introducing and supporting machine and deep learning technologies, and on the other hand, analyzing the ethical-philosophical implications deriving from the new scenarios that these disciplines open up. Rosario has authored two books, and he is a speaker at international research centers and conferences as well as a trainer and technical/scientific consultant on the huge and changing world of AI. Currently, he is working as a CTO with one of the oldest AI companies in Italy.

About the reviewers

Alessio Ligios is a dynamic data scientist, renowned for his proficiency in data analysis and machine learning. With a solid foundation in science and engineering, Alessio excels in transforming intricate data into practical business solutions. In his current role at Live Tech - Amplify your Data, Alessio has demonstrated his expertise by developing and implementing advanced textual content classification models. He excels in predictive modeling, leveraging machine learning (ML) and deep learning (DL) algorithms for accurate trend forecasting. Educationally, Alessio holds a master’s degree in computer science from Università degli Studi Roma Tre with a distinguished vote of 110/110.

Corrado Silvestri is a computer engineer. He earned a master’s degree from Roma Tre University with a GPA of 100/110. Passionate about the realm of AI and ML, he has produced models and projects of many types, such as forecasting, NLP, and computer vision, establishing the groundwork for his present position as a data scientist at a company that is verticalized in AI. An expert in the analytical phase and data manipulation, he has implemented AI models and solutions, expanding his technical experience and excelling in this field. He is a specialist at finding the perfect compromise by combining engineering expertise, data manipulation, and AI to build cutting-edge solutions for businesses in a variety of industries.

Table of Contents

Preface

Part 1: Getting Started with Streamlit

1

Getting to Know Streamlit – A Brief Overview

The importance of turning an idea into a prototype – the changing scenario in computing methods

The importance of a full Python web framework

Local versus the cloud

Python libraries for web applications (Flask and Django)

Examples of Streamlit’s capabilities

The importance of turning an idea into a prototype

Summary

2

Setting Up the Python Coding Environment

Technical requirements

Setting up the OS

IDE selection

What is a virtual environment?

Summary

3

Exploring Streamlit’s Features and Functionality

Technical requirements

Installing and launching Streamlit

Streamlit features and widgets

Colored textboxes

Images, audio, and video

Inputting text and numbers

Slider

Balloons

DataFrames, plots, and visualizations

Date, time, and more

Summary

Part 2: Building a Basic Web App for Essential Streamlit Skills

4

Streamlit Essentials – Configuring the Environment, Managing Packages, and More

Technical requirements

Configuring our environment

Installing and importing packages

App skeleton building

Building the menu and adding decorations

Summary

5

Organizing and Displaying Content with Columns, Expanders, and NLP Techniques

Technical requirements

Organizing and arranging content in a web app

Adding decorations

Adding the Text Analysis part

Hiding and showing parts depending on importance

Adding columns, expanders, and a textbox

Adding the two basic functions

Adding a wordcloud

Introducing NLP concepts – tokens and lemmas

Adding the summarization function

Tokens and lemmas

Using the text_analysis function

Summary

6

Implementing NLP Techniques for Text Analysis and Processing in Streamlit

Technical requirements

Deep-diving into NLP techniques

What is translation?

What is sentiment analysis?

Deep-diving into language translation

Adding a text area

Performing the translation task

Diving deep into sentiment analysis

Recap of our first web application

Summary

7

Sharing and Deploying Your Apps on the Cloud Using Streamlit Share

Technical requirements

Understanding the importance of deployment

Best practices in web application deployment

Additional benefits of web application deployment

What are Streamlit Share and Streamlit Cloud?

A quick introduction to GitHub

Getting familiar with the Streamlit Share service

Summary

Part 3: Developing Advanced Skills with a Covid-19 Detection Tool

8

Advanced Environment Setup and Package Management for Building an AI-Powered Web App

Technical requirements

Configuring our environment

Installing and importing packages

Building the app skeleton

Building the menu and adding decorations

Summary

9

Optimizing Streamlit Web App UX with Customization and UI Features

Technical requirements

Dealing with more advanced web app features

Adding the Image Enhancement section using the Pillow library

Contrast

Brightness

Original

Adding the Disclaimer and Info section

Summary

10

Utilizing Pretrained Models to Create Specialized and Personalized Web Applications

Technical requirements

Understanding the benefits of pretrained ML models

Creating customized web apps to improve user experience

Utilizing predictions from ML

Summary

11

Deploying and Managing Complex Libraries on Streamlit Share

Technical requirements

Consolidating cloud deployment skills

Avoiding bad behavior

Creating a list of all the packages that were installed and used to develop the Python code

Creating a GitHub repository

Avoiding runtime errors

Managing difficult libraries

Deploying the app on Streamlit Cloud

Summary

Part 4: Advanced Techniques for Secure and Customizable Web Applications

12

Smart File Uploading – Advanced Techniques for Professional Web Applications

Technical requirements

Understanding the customized features of the file uploader

Creating a new virtual environment

Building the app skeleton

Creating a radio button for the app menu

Creating a suitable file uploader for web apps

Simplifying web apps with smart components

Summary

13

Creating a Secure Login and Signup Process for Web Applications

Technical requirements

Understanding the logic behind the login and signup page

What is SHA-256 and why should we use it?

Connecting to a relational database and interacting with it

Creating the Login menu

Creating the Sign Up menu

Running the app

Adding a graphical user interface

Retrieving or saving credentials from and to the database

Summary

14

Customizing Pages, Personalizing Themes, and Implementing Multi-Pages

Technical requirements

Understanding new features related to deep customization

Creating deeply customized pages

Understanding theming and .toml files

Exploring the multi-pages feature

Creating multi-pages

Passing a variable from one page to another

Summary

15

Enhancing Web Apps with Forms, Session State, and Customizable Subdomains

Technical requirements

What are forms and when and why do we use them?

The context manager approach

The classic approach

What is Session State and when do we use it?

What are customizable subdomains and what possibilities do they offer?

Summary

16

Takeaways and Conclusion

How and when to use our web app working template

How and when to use databases and advanced skills

How to deploy web applications on the cloud

Farewell!

Index

Other Books You May Enjoy

Preface

In the swiftly evolving landscape of web application development, the desire to transform innovative ideas into functional web apps has never been more pressing. Web App Development Made Simple with Streamlit is a book that emerges as a beacon for those who seek to navigate this dynamic domain with ease and confidence. This book is meticulously crafted for a diverse range of professionals who share a common goal – the rapid transformation of code into working web applications.

At its core, Web App Development Made Simple with Streamlit is more than just a guide; it’s a journey. It takes you from the fundamentals of Streamlit, a powerful tool that simplifies web app development, to the intricate processes of deploying your solutions on cloud services. This journey is designed to be accessible, empowering you to make your applications available to a vast, global audience with minimal hassle.

Throughout the book, you’ll find a harmonious blend of theoretical knowledge and practical application. The chapters are structured to provide a clear, step-by-step guide, ensuring that even those new to web development can follow along with ease. Moreover, the book is peppered with real-world examples and case studies, providing you with a tangible understanding of how Streamlit can be leveraged in various scenarios.

As you delve into the pages of this book, expect to embark on a transformative learning experience. You’ll gain not just the skills to develop web applications but also the vision to see the potential of your code in the digital world. This book is your companion in unlocking the power of Streamlit, simplifying web app development, and bringing your ideas to the global stage.

Who this book is for

This book is tailored for Python programmers looking to transform their scripts into interactive web applications. It’s an essential resource for web developers seeking to streamline their prototyping process using Streamlit’s intuitive framework. Computer science students will find this book a practical guide for applying their theoretical knowledge to real-world web app development. IT professionals and enthusiasts eager to explore the realm of web app creation, especially those keen on deploying applications quickly and efficiently, will discover invaluable insights within these pages. Essentially, this book is a comprehensive toolkit for anyone passionate about bringing web app ideas to life with simplicity and speed.

What this book covers

Chapter 1, Getting to Know Streamlit – A Brief Overview, introduces Streamlit’s role in web app development. The chapter offers an overview of Streamlit’s user-friendly features and capabilities, as well as insight into rapid development with Streamlit.

Chapter 2, Setting Up the Python Coding Environment, includes a step-by-step guide for Python environment setup. The chapter includes tips for efficient Streamlit integration and focuses on creating a streamlined development workflow.

Chapter 3, Exploring Streamlit’s Features and Functionality, explores Streamlit’s functionalities in detail. Practical examples showcasing its versatility are included. The chapter also offers insights into Streamlit’s unique feature set.

Chapter 4, Streamlit Essentials – Configuring the Environment, Managing Packages, and More, describes key techniques for Streamlit environment configuration as well as best practices for efficient package management. Tips for optimizing the Streamlit setup are included.

Chapter 5, Organizing and Displaying Content with Columns, Expanders, and NLP Techniques, explores strategies for content organization using Streamlit’s tools. The chapter introduces natural language processing (NLP) techniques for enhanced content management and describes methods for effective data presentation.

Chapter 6, Implementing NLP Techniques for Text Analysis and Processing in Streamlit, teaches you how to apply NLP for text analysis within Streamlit. A step-by-step guide for NLP integration and case studies showcasing NLP in web app development are included.

Chapter 7, Sharing and Deploying Your Apps on the Cloud Using Streamlit Share, describes instructions for cloud deployment using Streamlit Share. Tips for making apps accessible globally are included. The chapter also offers insights into cloud-based app sharing.

Chapter 8, Advanced Environment Setup and Package Management for Building an AI-Powered Web App, teaches you advanced setup techniques for AI-driven web apps. Package management for AI integration and strategies for setting up an efficient AI web app environment are explained in detail.

Chapter 9, Optimizing Streamlit Web App UX with Customization and UI Features, explains how to enhance user experience through Streamlit customization. The chapter also explores UI features for functional aesthetics. Techniques for UI-driven app optimization are described.

Chapter 10, Utilizing Pretrained Models to Create Specialized and Personalized Web Applications, delves into the integration of pretrained models in web apps. The chapter explains how to create specialized, user-centric applications. Personalization strategies using AI models are described.

Chapter 11, Deploying and Managing Complex Libraries on Streamlit Share, explores techniques for deploying complex libraries on Streamlit Share. Strategies for managing robust app performance and complex library integration are included.

Chapter 12, Smart File Uploading – Advanced Techniques for Professional Web Applications, explains advanced file uploading methods for professionalism. The chapter teaches you how to streamline file uploads for user ease and enhance web apps with efficient file management.

Chapter 13, Creating a Secure Login and Signup Process for Web Applications, shows you how to design secure authentication processes, ensure user data protection, and implement robust login/signup systems in web apps.

Chapter 14, Customizing Pages, Personalizing Themes, and Implementing Multi-Pages, describes techniques for unique page customization. The chapter teaches you how to personalize themes for brand identity and utilize multi-page layouts for complex apps.

Chapter 15, Enhancing Web Apps with Forms, Session State, and Customizable Subdomains, teaches you how to utilize forms and session states for dynamic content. The chapter also describes how to implement customizable subdomains for branding. Strategies for enhancing web apps with advanced features are explored.

Chapter 16, Takeaways and Conclusion, summarizes the book’s essential insights and what you have learned, reflecting on Streamlit’s impact on web app development and offering concluding thoughts on future trends.

To get the most out of this book

You will need an understanding of the basics of Python programming and the Linux Terminal.

If you are using the digital version of this book, we advise you to type the code yourself or access the code from the book’s GitHub repository (a link is available in the next section). Doing so will help you avoid any potential errors related to the copying and pasting of code.

Download the example code files

You can download the example code files for this book from GitHub at https://github.com/PacktPublishing/Web-App-Development-Made-Simple-with-Streamlit. If there’s an update to the code, it will be updated in the GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: Let’s check whether pip is installed in our Ubuntu box.

A block of code is set as follows:

st.header(This is a header)

st.subheader(This is a subheader)

st.text(This is a simple text)

st.write(This is a write dimension)

Any command-line input or output is written as follows:

pip --version (or pip3 --version)

Bold: Indicates a new term, an important word, or words that you see on screen. For instance, words in menus or dialog boxes appear in bold. Here is an example: We have also completed the Text Analysis and About sections of the menu.

Tips or important notes

Appear like this.

Get in touch

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