$ python main.py

Hello World from Python
```

</div>

/// tip | Совет

Подробнее об этом можно прочитать на сайте <a href="https://12factor.net/config" class="external-link" target="_blank">The Twelve-Factor App: Config</a>.

///

## Типизация и Валидация { #types-and-validation }

from fastapi import FastAPI, Response

app = FastAPI()


@app.get("/headers-and-object/")
def get_headers(response: Response):
    response.headers["X-Cat-Dog"] = "alone in the world"

from fastapi import FastAPI

app = FastAPI()


@app.get("/users/me")
async def read_user_me():
    return {"user_id": "the current user"}


@app.get("/users/{user_id}")
async def read_user(user_id: str):

from contextlib import AsyncExitStack

from starlette.types import ASGIApp, Receive, Scope, Send


# Used mainly to close files after the request is done, dependencies are closed
# in their own AsyncExitStack
class AsyncExitStackMiddleware:
    def __init__(
        self, app: ASGIApp, context_name: str = "fastapi_middleware_astack"
    ) -> None:
        self.app = app
        self.context_name = context_name

    description: Union[str, None] = None
    price: float
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}


@app.get("/items/{item_id}", response_model=Item, response_model_exclude_unset=True)

Закрывающий статус код можно использовать из <a href="https://tools.ietf.org/html/rfc6455#section-7.4.1" class="external-link" target="_blank">valid codes defined in the specification</a>.

///

### Веб-сокеты с зависимостями: проверка в действии { #try-the-websockets-with-dependencies }

Если ваш файл называется `main.py`, то запустите приложение командой:

<div class="termy">

```console
$ fastapi dev main.py

 * [okhttp-stats](https://github.com/flipkart-incubator/okhttp-stats): Get stats like average network speed.
 * [okhttp-system-keystore](https://github.com/charleskorn/okhttp-system-keystore): Use trusted certificates from the operating system keystore (Keychain on macOS, Certificate Store on Windows).

        NtlmHttpServletRequest request = new NtlmHttpServletRequest(mockRequest, mockPrincipal);
        assertEquals("NTLM", request.getAuthType());
        // Verify it returns the same value on multiple calls
        assertEquals("NTLM", request.getAuthType());
    }

O **FastAPI** **extrairá** os dados para **cada campo** dos **parâmetros de consulta** presentes na requisição, e fornecerá o modelo Pydantic que você definiu.


## Verifique os Documentos { #check-the-docs }

Você pode ver os parâmetros de consulta nos documentos de IU em `/docs`:

<div class="screenshot">
<img src="/img/tutorial/query-param-models/image01.png">
</div>

# Test with parts from, and to verify the report in:
# https://github.com/fastapi/fastapi/discussions/14177
# Made an issue in:
# https://github.com/fastapi/fastapi/issues/14247
from enum import Enum

from fastapi import FastAPI
from fastapi.testclient import TestClient
from inline_snapshot import snapshot
from pydantic import BaseModel, Field


class MessageEventType(str, Enum):
    alpha = "alpha"
    beta = "beta"