Fastapi Tutorial Pdf File

FastAPI provides built-in support for testing using Pytest. Here's an example:

from fastapi.testclient import TestClient
from main import app
client = TestClient(app)
def test_read_root():
    response = client.get("/")
    assert response.status_code == 200
    assert response.json() == "Hello": "World"

In this example, we define a test that checks the response of the root URL.

To start with FastAPI, you'll need to install it using pip:

pip install fastapi

You'll also need to install an ASGI server like uvicorn: fastapi tutorial pdf

pip install uvicorn

Create a file named main.py:

from fastapi import FastAPI
app = FastAPI()
@app.get("/")
async def root():
return "message": "Hello World"
 FastAPI provides built-in support for testing using Pytest

Run the server:

uvicorn main:app --reload

Visit http://127.0.0.1:8000. You’ll see the JSON response. Now visit http://127.0.0.1:8000/docs – a fully interactive Swagger UI appears automatically. In this example, we define a test that

Key takeaway: FastAPI turns your Python function into a complete API endpoint with zero extra boilerplate.

from typing import Optional, Union
class UpdateItem(BaseModel):
name: Optional[str] = None
price: Union[float, None] = None