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

Retrieving or saving credentials from and to the database

From a theoretical point of view, we have already discussed what a hash is and why we should use one. From a practical point of view, there are many Python packages available (for example, sha256 and pycrypto), but one of the easiest to use that’s also very effective is hashlib. This library is installed in Python by default, so we don’t have to install it in our virtual environment; all we have to do is import it into our app.py file.

While leveraging hashlib, all we need to do is use its sha256 method to create the hash encryption of the password. Once again, let me highlight that SHA-256 is a very strong form of encryption from a security perspective.

These are the new lines of code we need for the hashing process:

Figure 13.17: The make_hashes function

Figure 13.17: The make_hashes function

Here’s a breakdown of what we did:

  • On line 5, we imported hashlib.
  • On lines 12 and 13, we created a new...