* How to set **validation constraints** as `maximum_length` or `regex`.
* A very powerful and easy to use **<abbr title="also known as components, resources, providers, services, injectables">Dependency Injection</abbr>** system.
* Security and authentication, including support for **OAuth2** with **JWT tokens** and **HTTP Basic** auth.

通过依赖注入系统，只要告诉 **FastAPI** *路径操作函数* 还要「依赖」其他在*路径操作函数*之前执行的内容，**FastAPI** 就会执行函数代码，并「注入」函数返回的结果。

其他与「依赖注入」概念相同的术语为：

* 资源（Resource）
* 提供方（Provider）
* 服务（Service）
* 可注入（Injectable）
* 组件（Component）

## **FastAPI** 插件

**依赖注入**系统支持构建集成和「插件」。但实际上，FastAPI 根本**不需要创建「插件」**，因为使用依赖项可以声明不限数量的、可用于*路径操作函数*的集成与交互。

创建依赖项非常简单、直观，并且还支持导入 Python 包。毫不夸张地说，只要几行代码就可以把需要的 Python 包与 API 函数集成在一起。

```bash
helm delete my-release
```

or

```bash
helm uninstall my-release
```

		Short: "Manage istiod logging.",
		Long:  "Retrieve or update logging levels of istiod components.",
		Example: `  # Retrieve information about istiod logging levels.
  istioctl admin log

  # Retrieve information about istiod logging levels on a specific control plane pod.

                String errMsg = "Missing Javadoc file for " + link + " in " + sourceFile.getName();
                if (link.startsWith("javadoc")) {
                    errMsg += " (You may need to remove the leading `javadoc` path component)";
                }
                errorsForFile.add(new Error(lineNumber, line, errMsg));
            }
            // TODO: Also parse the HTML in the javadoc file to check if the specific method is present

        sink.writeUtf8("Content-Type: ")
          .writeUtf8(contentType.toString())
          .write(CRLF)
      }

      // We can't measure the body's size without the sizes of its components.
      val contentLength = body.contentLength()
      if (contentLength == -1L && countBytes) {
        byteCountBuffer!!.clear()
        return -1L
      }

      sink.write(CRLF)

 * A lock's behavior when a cycle is detected, however, is defined by the {@code Policy} of the
 * factory that created it. This allows detection of cycles across components while delegating
 * control over lock behavior to individual components.
 *
 * <p>Applications are encouraged to use a {@code CycleDetectingLockFactory} to create any locks for
 * which external/unmanaged code is executed while the lock is held. (See caveats under

 *      </td>
 *   </tr>
 * </table>
 * <p>This is only a small set of all the options. A complete list can be found at
 * <a href="https://maven.apache.org/components/plugin-tools/maven-plugin-tools-annotations/index.html" target="_blank">
 * Maven Plugin Tool for Annotations</a>.
 *

# 🔗

**FastAPI** ✔️ 📶 🏋️ ✋️ 🏋️ **<abbr title="also known as components, resources, providers, services, injectables">🔗 💉</abbr>** ⚙️.

⚫️ 🏗 📶 🙅 ⚙️, &amp; ⚒ ⚫️ 📶 ⏩ 🙆 👩‍💻 🛠️ 🎏 🦲 ⏮️ **FastAPI**.

## ⚫️❔ "🔗 💉"

**"🔗 💉"** ⛓, 📋, 👈 📤 🌌 👆 📟 (👉 💼, 👆 *➡ 🛠️ 🔢*) 📣 👜 👈 ⚫️ 🚚 👷 &amp; ⚙️: "🔗".

&amp; ⤴️, 👈 ⚙️ (👉 💼 **FastAPI**) 🔜 ✊ 💅 🔨 ⚫️❔ 💪 🚚 👆 📟 ⏮️ 📚 💪 🔗 ("💉" 🔗).

👉 📶 ⚠ 🕐❔ 👆 💪:

  optional ContainerResourceMetricSource containerResource = 7;

  // external refers to a global metric that is not associated
  // with any Kubernetes object. It allows autoscaling based on information
  // coming from components running outside of cluster
  // (for example length of queue in cloud messaging service, or
  // QPS from loadbalancer running outside of cluster).
  // +optional
  optional ExternalMetricSource external = 5;
}