from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()


@app.post("/items/", response_model=Item, summary="Create an item")
async def create_item(item: Item):
    """
    Create an item with all the information:

    - **name**: each item must have a name

import pytest
from fastapi import FastAPI
from fastapi.exceptions import FastAPIError


class NonPydanticModel:
    pass


def test_invalid_response_model_raises():
    with pytest.raises(FastAPIError):
        app = FastAPI()

        @app.get("/", response_model=NonPydanticModel)
        def read_root():
            pass  # pragma: nocover


def test_invalid_response_model_sub_type_raises():

from fastapi import APIRouter, FastAPI
from fastapi.testclient import TestClient


def test_redirect_slashes_enabled():
    app = FastAPI()
    router = APIRouter()

    @router.get("/hello/")
    def hello_page() -> str:
        return "Hello, World!"

    app.include_router(router)

    client = TestClient(app)

    response = client.get("/hello/", follow_redirects=False)
    assert response.status_code == 200

     * environment.
     */
    public Type3Message() {
        setFlags(getDefaultFlags());
        setDomain(getDefaultDomain());
        setUser(getDefaultUser());
        setWorkstation(getDefaultWorkstation());
    }

    /**
     * Creates a Type-3 message in response to the given Type-2 message
     * using default values from the current environment.
     *

import jp.gr.java_conf.dangan.util.lha.LhaFile;
import jp.gr.java_conf.dangan.util.lha.LhaHeader;

/**
 * Extractor implementation for LHA (LZH) archive files.
 * This extractor can extract text content from files within LHA archives
 * by using appropriate extractors for each contained file type.
 *
 * @author shinsuke
 */
public class LhaExtractor extends AbstractExtractor {
    /** Logger for this class. */

import importlib

import pytest
from dirty_equals import IsList
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial005_py39"),
        pytest.param("tutorial005_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.body_nested_models.{request.param}")

from fastapi import APIRouter, FastAPI
from fastapi.responses import HTMLResponse, JSONResponse, PlainTextResponse
from fastapi.testclient import TestClient


class OverrideResponse(JSONResponse):
    media_type = "application/x-override"


app = FastAPI()
router_a = APIRouter()
router_a_a = APIRouter()
router_a_b_override = APIRouter()  # Overrides default class
router_b_override = APIRouter()  # Overrides default class

## Import `Field` { #import-field }

First, you have to import it:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning

Notice that `Field` is imported directly from `pydantic`, not from `fastapi` as are all the rest (`Query`, `Path`, `Body`, etc).

///

## Declare model attributes { #declare-model-attributes }

You can then use `Field` with model attributes:

* ...etc.

Nevertheless, you might have a very specific use case where you really need to disable the API docs for some environment (e.g. for production) or depending on configurations from environment variables.

## Conditional OpenAPI from settings and env vars { #conditional-openapi-from-settings-and-env-vars }

You can easily use the same Pydantic settings to configure your generated OpenAPI and the docs UIs.

For example:

 *
 * @author mbechler
 */
public class AvFlags extends AvPair {

    /**
     * Constructs an AV flags pair from raw bytes
     * @param raw the raw flag bytes
     */
    public AvFlags(final byte[] raw) {
        super(AvPair.MsvAvFlags, raw);
    }

    /**
     * Constructs an AV flags pair from integer flags
     * @param flags the flag values as integer
     */
    public AvFlags(final int flags) {