try:
    import email_validator

    assert email_validator  # make autoflake ignore the unused import
    from pydantic import EmailStr
except ImportError:  # pragma: no cover

    class EmailStr(str):  # type: ignore
        @classmethod
        def __get_validators__(cls) -> Iterable[Callable[..., Any]]:
            yield cls.validate

        @classmethod

And as you can have parallelism and asynchronicity at the same time, you get higher performance than most of the tested NodeJS frameworks and on par with Go, which is a compiled language closer to C <a href="https://www.techempower.com/benchmarks/#section=data-r17&hw=ph&test=query&l=zijmkf-1" class="external-link" target="_blank">(all thanks to Starlette)</a>.

### Is concurrency better than parallelism?

            )  # pragma: no cover


def test_websocket_invalid_data():
    client = TestClient(app)
    with pytest.raises(WebSocketDisconnect):
        with client.websocket_connect("/items/foo/ws?q=bar&token=some-token"):
            pytest.fail(
                "did not raise WebSocketDisconnect on __enter__"

from docs_src.background_tasks.tutorial001 import app

client = TestClient(app)


def test():
    log = Path("log.txt")
    if log.is_file():
        os.remove(log)  # pragma: no cover
    response = client.post("/send-notification/******@****.***")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Notification sent in the background"}

    * 基于 **Nginx** 的 Docker 服务器（优化了 Vue-router 配置）
    * Docker 多阶段构建，无需保存或提交编译的代码
    * 在构建时运行前端测试（可禁用）
    * 尽量模块化，开箱即用，但仍可使用 Vue CLI 重新生成或创建所需项目，或复用所需内容
* 使用 **PGAdmin** 管理 PostgreSQL 数据库，可轻松替换为 PHPMyAdmin 或 MySQL
* 使用 **Flower** 监控 Celery 任务
* 使用 **Traefik** 处理前后端负载平衡，可把前后端放在同一个域下，按路径分隔，但在不同容器中提供服务
* Traefik 集成，包括自动生成 Let's Encrypt **HTTPS** 凭证
* GitLab **CI**（持续集成），包括前后端测试

## 全栈 FastAPI + Couchbase

By default, those files are served from a <abbr title="Content Delivery Network: A service, normally composed of several servers, that provides static files, like JavaScript and CSS. It's commonly used to serve those files from the server closer to the client, improving performance.">CDN</abbr>.

But it's possible to customize it, you can set a specific CDN, or serve the files yourself.

## Custom CDN for JavaScript and CSS

@app.get(
    "/a",
    response_class=Response,
    responses={500: {"description": "Error", "model": JsonApiError}},
)
async def a():
    pass  # pragma: no cover


@app.get("/b", responses={500: {"description": "Error", "model": Error}})
async def b():
    pass  # pragma: no cover


client = TestClient(app)


def test_openapi_schema():
    response = client.get("/openapi.json")

from fastapi.exceptions import FastAPIError


def test_invalid_response_model():
    with pytest.raises(FastAPIError):
        from docs_src.response_model.tutorial003_04 import app

from ...utils import needs_py310


@needs_py310
def test_invalid_response_model():
    with pytest.raises(FastAPIError):
        from docs_src.response_model.tutorial003_04_py310 import app

    username: str


class ModelC(ModelB):
    password: str


class ModelA(BaseModel):
    name: str
    description: Optional[str] = None
    model_b: ModelB

    @validator("name")
    def lower_username(cls, name: str, values):
        if not name.endswith("A"):
            raise ValueError("name must end in A")
        return name


async def get_model_c() -> ModelC: