FastAPI Tutorial - From Zero to Hero

A progressive tutorial for learning FastAPI, where each example builds upon the previous one.

Prerequisites

• Python 3.11 or higher
• Basic understanding of Python
• Familiarity with REST APIs (helpful but not required)

Setup

This project uses uv as the package manager.

Install uv

# macOS/Linux
curl -LsSf https://astral.sh/uv/install.sh | sh

# Windows
powershell -c "irm https://astral.sh/uv/install.ps1 | iex"

Initialize the Project

# Create a new directory
mkdir fastapi-tutorial
cd fastapi-tutorial

# Initialize with uv
uv init

# Add FastAPI and uvicorn
uv add fastapi uvicorn[standard]

Run Examples

Each example can be run with:

uv run uvicorn example_XX:app --reload

Then visit http://localhost:8000 in your browser.

Tutorial Structure

Part 1: Basics

• Example 01: Hello World - Your first FastAPI application
• Example 02: Path Parameters - Dynamic routes
• Example 03: Query Parameters - URL parameters

Part 2: Request Handling

• Example 04: Request Body - Handling POST requests with Pydantic
• Example 05: Response Models - Structured responses
• Example 06: Status Codes - HTTP status codes

Part 3: Advanced Features

• Example 07: Path Operations - Multiple HTTP methods
• Example 08: Dependencies - Dependency injection
• Example 09: Error Handling - Custom exception handlers

Part 4: Real-World Application

• Example 10: Complete CRUD API - A todo list application

Learning Path

Follow the examples in order. Each example includes:

• Python code file (example_XX.py)
• Explanation document (example_XX.md)
• Key concepts demonstrated
• What's new compared to the previous example

Documentation

FastAPI automatically generates interactive API documentation:

• Swagger UI: http://localhost:8000/docs
• ReDoc: http://localhost:8000/redoc

Resources

• FastAPI Official Documentation
• Pydantic Documentation
• Python Type Hints