API Development

Building web APIs with FastAPI — from your first endpoint through request validation, data modeling, real-time streaming, and dependency injection.

Topics

• FastAPI Intro — Modern Python web framework with async support, automatic validation, and comparison to Flask/Django

• What ASGI Is — The async successor to WSGI: how Uvicorn and FastAPI communicate, WebSockets, HTTP/2, and background tasks

• Path Parameters — Capturing variables from URL paths with type conversion and validation

• Query Parameters — Default values, optional parameters, type validation, and grouping into Pydantic models

• Header & Cookie Parameters — Extracting and validating HTTP headers, authentication tokens, and custom headers

• Request Body — Declaring and validating JSON request bodies with Pydantic

• Data Modeling (Pydantic) — BaseModel, validation rules, nested models, and response_model control

• Server-Sent Events — Real-time server-to-client streaming with FastAPI’s native SSE support for LLM responses and live updates

• Dependency Injection — FastAPI’s Depends() system for building dependency graphs (database sessions, auth, etc.)

Prerequisites

Complete Foundations first.

• FastAPI Intro
• What ASGI Is
• What are Path Parameters in FastAPI?
• FastAPI Code Examples for Query Parameters
• Header Parameters in FastAPI
• Body in FastAPI
• Data Modeling (Pydantic)
• Server-Sent Events (SSE)
• Dependency Injection
• Practice — API Development
• Assessment — API Development