We’ll start by learning FastAPI’s key features and core use cases. Then we will run our first application and test it out! Finally, we will learn the details of supporting GET and POST operations that include request parameters and build and test those endpoints.

Why FastAPI?

First application

FastAPI vs. Django

GET operations

Hello world

Hello who?

POST operations

Pydantic model

POST operation in action

FastAPI Basics

We’ll start by learning how to support PUT and DELETE operations using FastAPI. Then we will learn how to handle different kinds of errors and always return an appropriate status code in the response. Lastly we'll learn how to use async to enable concurrent requests that can handle higher workloads.

PUT and DELETE operations

from fastapi import FastAPI
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    ____: str
    ____: str

# Define items at application start
items = {"bananas": "Yellow fruit."}

app = FastAPI()


@app.put("/items")
def update_item(item: Item):
    name = item.name
    # Update the description
    items[____] = item.____
    return item

from fastapi import FastAPI
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    name: str
    description: str

# Define items at application startup
items = {"bananas": "Yellow fruit."}

app = FastAPI()


@app.put("/items")
def update_item(item: Item):
    name = item.name
    # Update the description
    items[name] = item.description
    return item

PUT operation in action

from fastapi import FastAPI
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    ____: str

# Define items at application start
items = {"apples", "oranges", "bananas"}

app = FastAPI()


@app.delete("/items")
def delete_item(item: Item):
    name = item.name
    # Delete the item
    items.remove(____)
    return {}

from fastapi import FastAPI
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    name: str

# Define items at application startup
items = {"apples", "oranges", "bananas"}

app = FastAPI()


@app.delete("/items")
def delete_item(item: Item):
    name = item.name
    # Delete the item
    items.remove(name)
    return {}

DELETE operation in action

Handling errors

Options

Success

Not Success

Status code classification

from fastapi import FastAPI, ____
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    name: str

# Define items at application startup
items = {"apples", "oranges"}

app = FastAPI()


@app.delete("/items")
def delete_item(item: Item):
    name = item.name
    if name in items:
        items.remove(name)
    else:
        # Raise HTTPException with status code for "not found"
        raise ____(status_code=____, detail="Item not found.")
    return {}

from fastapi import FastAPI, HTTPException
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    name: str

# Define items at application startup
items = {"apples", "oranges"}

app = FastAPI()


@app.delete("/items")
def delete_item(item: Item):
    name = item.name
    if name in items:
        items.remove(name)
    else:
        # Raise HTTPException with status code for "not found"
        raise HTTPException(status_code=404, detail="Item not found.")
    return {}

Handling a client error

Using async for concurrent work

When should we use async?

from fastapi import FastAPI, HTTPException
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    name: str

app = FastAPI()

items = {"rock", "paper", "scissors"}


@app.delete("/items")
# Make asynchronous
____ def root(item: Item):
    name = item.name
    # Check if name is in items
    if ____ not in ____:
        # Return the status code for not found
        raise HTTPException(status_code=___, detail="Item not found.")
    items.remove(name)
    return {"message": "Item deleted"}

from fastapi import FastAPI, HTTPException
from pydantic import BaseModel

# Define model Item
class Item(BaseModel):
    name: str

app = FastAPI()

items = {"rock", "paper", "scissors"}


@app.delete("/items")
# Make asynchronous
async def root(item: Item):
    name = item.name
    # Check if name is in items
    if name not in items:
        # Return the status code for not found
        raise HTTPException(status_code=404, detail="Item not found.")
    items.remove(name)
    return {"message": "Item deleted"}

Asynchronous DELETE operation

FastAPI Advanced topics

We'll start by learning how to write system tests to validate individual FastAPI endpoints. Next we'll build a full JSON CRUD API to manage object lifecycles over HTTP. Finally, we'll learn how to test different application endpoints working together with manual functional tests.

FastAPI automated testing

Unit tests vs. system tests

System test

Building a JSON CRUD API

HTTP operations & CRUD steps

DELETE operation response

Complete JSON CRUD API

Writing a manual functional test

System tests vs. functional tests

Functional test

Wrap up

Building and testing a JSON CRUD API

This course teaches you to build production-grade web applications using FastAPI, a popular Python framework for creating APIs. You'll learn to handle all four HTTP operations, define request and response schemas, validate API requests, and return appropriate HTTP status codes. You'll also cover asynchronous code execution to boost performance, and by the end, you’ll develop a CRUD API and test workflows with Python's requests module. Tailored for experienced Python programmers, this course equips you with the skills to manage data with FastAPI, preparing you to build robust data management and ML model-serving pipelines.

<h2>Introduction to FastAPI and Its Applications</h2> APIs are commonly used to manage data on the web, and FastAPI is a popular new web framework for building APIs with Python. Data and Machine Learning Engineers leverage FastAPI to build applications that serve as context-aware data transactions and pipelines on the web.<br><br> <h2>Building Production-Grade Web Applications with FastAPI</h2> In this course, you will learn how to build production-grade web applications leveraging your Python skills with the FastAPI framework. By the end, you’ll understand core use cases for FastAPI in relation to other Python web frameworks. You’ll learn to build APIs using all four types of HTTP operations and define request and response schemas. In addition, you’ll validate API requests, respond with appropriate HTTP status codes and messages, and execute code asynchronously to improve application performance. A hands-on project will guide you through building a classical CRUD (Create, Read, Update, Delete) API, testing workflows using Python's requests module.<br><br> <h2>Course Goals and Target Audience</h2> This course is designed for experienced Python programmers who want to build web applications that manage data using FastAPI. Upon completing this course, you will have the foundation necessary to create FastAPI projects suited for high-throughput data management and ML model-serving pipelines.

Introduction to APIs in Python

Introduction to Object-Oriented Programming in Python

Build robust, production-grade APIs with FastAPI, mastering HTTP operations, validation, and async execution to create efficient data and ML pipelines.


When should we use async?

Exercice interactif pratique