Standardmäßig überprüft die Methode `.openapi()` die Eigenschaft `.openapi_schema`, um zu sehen, ob diese Inhalt hat, und gibt diesen zurück.

Ist das nicht der Fall, wird der Inhalt mithilfe der Hilfsfunktion unter `fastapi.openapi.utils.get_openapi` generiert.

Und diese Funktion `get_openapi()` erhält als Parameter:

* `title`: Der OpenAPI-Titel, der in der Dokumentation angezeigt wird.
* `version`: Die Version Ihrer API, z. B. `2.5.0`.

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

from ...utils import needs_py310


@pytest.fixture(name="client")
def get_client():
    from docs_src.extra_data_types.tutorial001_an_py310 import app

    client = TestClient(app)
    return client


@needs_py310
def test_extra_types(client: TestClient):
    item_id = "ff97dd87-a4a5-4a12-b412-cde99f33e00e"
    data = {

import pytest
from fastapi import FastAPI
from fastapi.testclient import TestClient

from ...utils import needs_py39


@pytest.fixture(name="app")
def get_app():
    from docs_src.request_files.tutorial003_py39 import app

    return app


@pytest.fixture(name="client")
def get_client(app: FastAPI):
    client = TestClient(app)
    return client


file_required = {
    "detail": [
        {

from fastapi.openapi.models import OAuth2 as OAuth2Model
from fastapi.openapi.models import OAuthFlows as OAuthFlowsModel
from fastapi.param_functions import Form
from fastapi.security.base import SecurityBase
from fastapi.security.utils import get_authorization_scheme_param
from starlette.requests import Request
from starlette.status import HTTP_401_UNAUTHORIZED, HTTP_403_FORBIDDEN

# TODO: import from typing when deprecating Python 3.9

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

from ...utils import needs_py310


@pytest.fixture(name="client")
def get_client():
    from docs_src.body_multiple_params.tutorial003_py310 import app

    client = TestClient(app)
    return client


@needs_py310
def test_post_body_valid(client: TestClient):
    response = client.put(
        "/items/5",
        json={

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

from ...utils import needs_py39


@pytest.fixture(name="client")
def get_client():
    from docs_src.bigger_applications.app_an_py39.main import app

    client = TestClient(app)
    return client


@needs_py39
def test_users_token_jessica(client: TestClient):
    response = client.get("/users?token=jessica")

But it was created before there existed Python type hints. So, to define every <abbr title="the definition of how data should be formed">schema</abbr> you need to use specific utils and classes provided by Marshmallow.

!!! check "Inspired **FastAPI** to"
    Use code to define "schemas" that provide data types and validation, automatically.

from fastapi.testclient import TestClient

from ..utils import needs_pydanticv1


@needs_pydanticv1
def test_recursive():
    from .app_pv1 import app

    client = TestClient(app)
    response = client.get("/items/recursive")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "sub_items": [{"name": "subitem", "sub_items": []}],
        "name": "item",
    }

from fastapi.testclient import TestClient

from ..utils import needs_pydanticv2


@needs_pydanticv2
def test_recursive():
    from .app_pv2 import app

    client = TestClient(app)
    response = client.get("/items/recursive")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "sub_items": [{"name": "subitem", "sub_items": []}],
        "name": "item",
    }

作为应用对象创建的组成部分，要注册 `/openapi.json` （或其它为 `openapi_url` 设置的任意内容）*路径操作*。

它只返回包含应用的 `.openapi()` 方法操作结果的 JSON 响应。

但默认情况下，`.openapi()` 只是检查 `.openapi_schema` 属性是否包含内容，并返回其中的内容。

如果 `.openapi_schema` 属性没有内容，该方法就使用 `fastapi.openapi.utils.get_openapi` 工具函数生成内容。

`get_openapi()` 函数接收如下参数：

* `title`：文档中显示的 OpenAPI 标题
* `version`：API 的版本号，例如 `2.5.0`
* `openapi_version`： OpenAPI 规范的版本号，默认为最新版： `3.0.2`
* `description`：API 的描述说明