Fastapi Tutorial Pdf Link -

FastAPI has a powerful Dependency Injection system. This allows you to share logic, enforce security, or handle database connections easily. from fastapi import Depends

When you need to send data from a client to your API, you use a request body. FastAPI uses Pydantic models to define the structure of the data you expect. from pydantic import BaseModel

Standards-based: Fully compatible with OpenAPI and JSON Schema. Setting Up Your Environment fastapi tutorial pdf

@app.get("/items/{item_id}")def read_item(item_id: int, q: str = None):return {"item_id": item_id, "q": q} To run the application, use the following command: uvicorn main:app --reload

Query Parameters: Used to filter or modify the request. In the read_item function, q is an optional query parameter because it has a default value of None. Request Body and Pydantic Models FastAPI has a powerful Dependency Injection system

class Item(BaseModel):name: strdescription: str = Noneprice: floattax: float = None @app.post("/items/")def create_item(item: Item):return item

High Performance: On par with NodeJS and Go, thanks to Starlette and pydantic. Fast Coding: Increases development speed by 200% to 300%. Fewer Bugs: Reduces human-induced errors by about 40%. Intuitive: Great editor support with completion everywhere. FastAPI uses Pydantic models to define the structure

Now, install FastAPI and Uvicorn, an ASGI server that will run your application: pip install fastapi uvicorn Creating Your First API Create a file named main.py and add the following code: from fastapi import FastAPI app = FastAPI() @app.get("/")def read_root():return {"Hello": "World"}

python -m venv venvsource venv/bin/activate # On Windows use venv\Scripts\activate

Path Parameters: Used to identify a specific resource. In /items/{item_id}, item_id is a path parameter. FastAPI uses Python type hints to validate the data type.