In those cases, you can use the *path operation decorator* parameter `response_model` instead of the return type.

You can use the `response_model` parameter in any of the *path operations*:

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* etc.

            200,
            {"X-Token values": ["foo", "bar"]},
        ),
    ],
)
def test(path, headers, expected_status, expected_response, client: TestClient):
    response = client.get(path, headers=headers)
    assert response.status_code == expected_status
    assert response.json() == expected_response


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

在文档界面中添加**路径操作**的标签和进行分组，请阅读 [教程 - 路径操作配置 - Tags 参数](../tutorial/path-operation-configuration.md#tags){.internal-link target=_blank} 文档。

## 文档的概要和描述 - OpenAPI

在文档界面中添加**路径操作**的概要和描述，请阅读 [教程 - 路径操作配置 - Summary 和 Description 参数](../tutorial/path-operation-configuration.md#summary-description){.internal-link target=_blank} 文档。

## 文档的响应描述 - OpenAPI

        when(systemSessionMock.getData()).thenReturn(sessionDataMock);

        Path beforePomFile =
                Paths.get("src/test/resources/projects/transform/before.pom").toAbsolutePath();
        Path afterPomFile =
                Paths.get("src/test/resources/projects/transform/after.pom").toAbsolutePath();
        Path tempFile = Files.createTempFile("", ".pom");
        Files.delete(tempFile);

tls              (on|off)    set to 'on' to enable TLS
tls_skip_verify  (on|off)    trust server TLS without verification, defaults to "on" (verify)
client_tls_cert  (path)      path to client certificate for mTLS auth
client_tls_key   (path)      path to client key for mTLS auth
version          (string)    specify the version of the Kafka cluster
comment          (sentence)  optionally add a comment to this setting
```

这意味着从环境变量中读取的**任何值**在 Python 中都将是一个 `str`，任何类型转换或验证都必须在代码中完成。

你将在[高级用户指南 - 设置和环境变量](./advanced/settings.md)中了解更多关于使用环境变量处理**应用程序设置**的信息。

## `PATH` 环境变量

有一个**特殊的**环境变量称为 **`PATH`**，操作系统（Linux、macOS、Windows）用它来查找要运行的程序。

`PATH` 变量的值是一个长字符串，由 Linux 和 macOS 上的冒号 `:` 分隔的目录组成，而在 Windows 上则是由分号 `;` 分隔的。

例如，`PATH` 环境变量可能如下所示：

//// tab | Linux, macOS

```plaintext
/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin
```

from pathlib import Path

from fastapi.testclient import TestClient

from docs_src.custom_response import tutorial009b_py39
from docs_src.custom_response.tutorial009b_py39 import app

client = TestClient(app)


def test_get(tmp_path: Path):
    file_path: Path = tmp_path / "large-video-file.mp4"
    tutorial009b_py39.some_file_path = str(file_path)
    test_content = b"Fake video bytes"
    file_path.write_bytes(test_content)

        Path path = getBaseDirectory()
                .resolve(Objects.requireNonNull(directory, "directory cannot be null"))
                .normalize();
        sources.removeIf(source -> source.scope() == scope
                && source.language() == language
                && source.directory().equals(path));
    }

    /**

                      path: secrets-svc/{{ tpl .existingSecret $ }}/{{ tpl .existingSecretKey $ }}
              {{- end }}
              {{- end }}
        {{- if .Values.tls.enabled }}
        - name: cert-secret-volume-mc
          secret:
            secretName: {{ .Values.tls.certSecret }}
            items:
              - key: {{ .Values.tls.publicCrt }}
                path: CAs/public.crt
        {{- end }}

Здесь переменная `app` будет экземпляром класса `FastAPI`.

Это будет основная точка взаимодействия для создания всего вашего API.

### Шаг 3: создайте *операцию пути (path operation)* { #step-3-create-a-path-operation }

#### Путь (path) { #path }

Здесь «путь» — это последняя часть URL, начиная с первого символа `/`.

Итак, в таком URL:

```
https://example.com/items/foo
```

...путь будет: