Book Image

Building Data Science Applications with FastAPI

By : François Voron
5 (1)
Book Image

Building Data Science Applications with FastAPI

5 (1)
By: François Voron

Overview of this book

FastAPI is a web framework for building APIs with Python 3.6 and its later versions based on standard Python-type hints. With this book, you’ll be able to create fast and reliable data science API backends using practical examples. This book starts with the basics of the FastAPI framework and associated modern Python programming language concepts. You'll be taken through all the aspects of the framework, including its powerful dependency injection system and how you can use it to communicate with databases, implement authentication and integrate machine learning models. Later, you’ll cover best practices relating to testing and deployment to run a high-quality and robust application. You’ll also be introduced to the extensive ecosystem of Python data science packages. As you progress, you’ll learn how to build data science applications in Python using FastAPI. The book also demonstrates how to develop fast and efficient machine learning prediction backends and test them to achieve the best performance. Finally, you’ll see how to implement a real-time face detection system using WebSockets and a web browser as a client. By the end of this FastAPI book, you’ll have not only learned how to implement Python in data science projects but also how to maintain and design them to meet high programming standards with the help of FastAPI.
Table of Contents (19 chapters)
1
Section 1: Introduction to Python and FastAPI
7
Section 2: Build and Deploy a Complete Web Backend with FastAPI
13
Section 3: Build a Data Science API with Python and FastAPI

Handling request parameters

The main goal of a REST API is to provide a structured way in which to interact with data. As such, it's crucial for the end user to send some information to tailor the response they need, such as path parameters, query parameters, body payloads, or headers.

To handle them, usually, web frameworks ask you to manipulate a request object to retrieve the parts you are interested in and manually apply validation. However, that's not necessary with FastAPI! Indeed, it allows you to define all of your parameters declaratively. Then, it'll automatically retrieve them in the request and apply validations based on the type hints. This is why we introduced type hinting in Chapter 2, Python Programming Specificities; it's used by FastAPI to perform data validation!

Next, we'll explore how you can use this feature to retrieve and validate this input data from different parts of the request.

Path parameters

The API path is the main...