import importlib

import pytest
from fastapi.testclient import TestClient


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial008b_py39"),
        pytest.param("tutorial008b_an_py39"),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.dependencies.{request.param}")

    client = TestClient(mod.app)
    return client

如果您正在开发**前端**，一个非常有趣的替代方案是 <a href="https://github.com/hey-api/openapi-ts" class="external-link" target="_blank">openapi-ts</a>。

## 生成一个 TypeScript 前端客户端

让我们从一个简单的 FastAPI 应用开始：

{* ../../docs_src/generate_clients/tutorial001_py39.py hl[7:9,12:13,16:17,21] *}

请注意，*路径操作* 定义了他们所用于请求数据和回应数据的模型，所使用的模型是`Item` 和 `ResponseMessage`。

### API 文档

如果您访问API文档，您将看到它具有在请求中发送和在响应中接收数据的**模式(schemas)**：

from types import ModuleType

import pytest
from fastapi.exceptions import FastAPIError
from fastapi.testclient import TestClient


@pytest.fixture(
    name="mod",
    params=[
        pytest.param("tutorial008c_py39"),
        pytest.param("tutorial008c_an_py39"),
    ],
)
def get_mod(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.dependencies.{request.param}")

    return mod

But it's the simplest way to focus on the server-side of WebSockets and have a working example:

{* ../../docs_src/websockets/tutorial001_py39.py hl[2,6:38,41:43] *}

## Create a `websocket` { #create-a-websocket }

In your **FastAPI** application, create a `websocket`:

{* ../../docs_src/websockets/tutorial001_py39.py hl[1,46:47] *}

/// note | Technical Details

You could also use `from starlette.websockets import WebSocket`.

from fastapi.testclient import TestClient

from docs_src.custom_response.tutorial009c_py39 import app

client = TestClient(app)


def test_get():
    response = client.get("/")

from fastapi.testclient import TestClient

from docs_src.response_cookies.tutorial001_py39 import app

client = TestClient(app)


def test_path_operation():
    response = client.post("/cookie/")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Come to the dark side, we have cookies"}

{* ../../docs_src/first_steps/tutorial001_py39.py hl[7] *}

Это функция на Python.

**FastAPI** будет вызывать её каждый раз, когда получает запрос к URL «`/`» с операцией `GET`.

В данном случае это асинхронная (`async`) функция.

---

Вы также можете определить её как обычную функцию вместо `async def`:

{* ../../docs_src/first_steps/tutorial003_py39.py hl[7] *}

/// note | Примечание

from fastapi.testclient import TestClient

from docs_src.response_cookies.tutorial002_py39 import app

client = TestClient(app)


def test_path_operation():
    response = client.post("/cookie-and-object/")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Come to the dark side, we have cookies"}

from docs_src.app_testing.tutorial001_py39 import client, test_read_main


def test_main():
    test_read_main()


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/": {
                "get": {

from fastapi.testclient import TestClient

from docs_src.wsgi.tutorial001_py39 import app

client = TestClient(app)


def test_flask():
    response = client.get("/v1/")
    assert response.status_code == 200, response.text
    assert response.text == "Hello, World from Flask!"


def test_app():
    response = client.get("/v2")
    assert response.status_code == 200, response.text