It might also help avoid confusion for new developers that see an unused parameter in your code and could think it's unnecessary.

///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

///

		Key:   config.APIKey,
		Value: "",
	},
	config.KV{
		Key:   config.Proxy,
		Value: "",
	},
}

// Config represents the subnet related configuration
type Config struct {
	// The subnet license token - Deprecated Dec 2021
	License string `json:"license"`

	// The subnet api key
	APIKey string `json:"apiKey"`

	// The HTTP(S) proxy URL to use for connecting to SUBNET
	Proxy string `json:"proxy"`

.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

假设现在包含**FastAPI** app的文件 `main.py`  有些其他**路径操作**。

有个 `GET` 操作会返回错误。

有个 `POST` 操作会返回一些错误。

所有*路径操作* 都需要一个`X-Token` 头。

//// tab | Python 3.10+

```Python
{!> ../../docs_src/app_testing/app_b_an_py310/main.py!}
```

////

//// tab | Python 3.9+

```Python

We see that we are going to need some dependencies used in several places of the application.

So we put them in their own `dependencies` module (`app/dependencies.py`).

We will now use a simple dependency to read a custom `X-Token` header:

//// tab | Python 3.9+

```Python hl_lines="3  6-8" title="app/dependencies.py"
{!> ../../docs_src/bigger_applications/app_an_py39/dependencies.py!}
```

////

//// tab | Python 3.8+

# OAuth2 实现密码哈希与 Bearer  JWT 令牌验证

至此，我们已经编写了所有安全流，本章学习如何使用 <abbr title="JSON Web Tokens">JWT</abbr> 令牌（Token）和安全密码哈希（Hash）实现真正的安全机制。

本章的示例代码真正实现了在应用的数据库中保存哈希密码等功能。

接下来，我们紧接上一章，继续完善安全机制。

## JWT 简介

JWT 即**JSON 网络令牌**（JSON Web Tokens）。

JWT 是一种将 JSON 对象编码为没有空格，且难以理解的长字符串的标准。JWT 的内容如下所示：

```

│   ├── main.py
│   └── test_main.py
```

➡️ 💬 👈 🔜 📁 `main.py` ⏮️ 👆 **FastAPI** 📱 ✔️ 🎏 **➡ 🛠️**.

⚫️ ✔️ `GET` 🛠️ 👈 💪 📨 ❌.

⚫️ ✔️ `POST` 🛠️ 👈 💪 📨 📚 ❌.

👯‍♂️ *➡ 🛠️* 🚚 `X-Token` 🎚.

//// tab | 🐍 3️⃣.6️⃣ & 🔛

```Python
{!> ../../docs_src/app_testing/app_b/main.py!}
```

////

//// tab | 🐍 3️⃣.1️⃣0️⃣ & 🔛

```Python

	}

	if subtle.ConstantTimeCompare([]byte(resp.Header.Get(xhttp.AmzRequestToken)), []byte(eventData.GetObjectContext.OutputToken)) != 1 {
		tokenErr := errorCodes.ToAPIErr(ErrInvalidToken)
		tokenErr.Description = "The request token included in the request is invalid"
		writeErrorResponse(ctx, w, tokenErr, r.URL)
		return
	}

	// Set all the relevant lambda forward headers if found.
	fwdHeadersToS3(resp.Header, w)

                                                        data-href="${contextPath}/admin/dict/kuromoji/details/${f:u(dictId)}/4/${f:u(data.id)}">
                                                    <td>${f:h(data.token)}</td>
                                                    <td>${f:h(data.reading)}</td>
                                                </tr>
                                            </c:forEach>

        final PagingList<KuromojiItem> itemList = kuromojiFile.selectList(0, 5);
        for (int i = 0; i < itemList.size(); i++) {
            final KuromojiItem kuromojiItem = itemList.get(i);
            assertEquals("token" + (i + 1), kuromojiItem.getToken());
            assertEquals("seg" + (i + 1), kuromojiItem.getSegmentation());
            assertEquals("reading" + (i + 1), kuromojiItem.getReading());

if [[ "${ISTIO_ENVOY_BASE_URL}" != "https://storage.googleapis.com/istio-build/proxy" ]]; then
  AUTH_HEADER="Authorization: Bearer $(gcloud auth print-access-token)"
  export AUTH_HEADER
fi

SIDECAR="${SIDECAR:-envoy}"

# OS-neutral vars. These currently only work for linux.
ISTIO_ENVOY_VERSION="${ISTIO_ENVOY_VERSION:-${PROXY_REPO_SHA}}"