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。

                    "schema": {
                        "$ref": "#/components/schemas/Message"
                    }
                }
            }
        },
        "200": {
            "description": "Successful Response",
            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/Item"
                    }
                }

    * Esta extensão SNI permite que um único servidor (com um único endereço IP) tenha vários certificados HTTPS e atenda a vários domínios / aplicativos HTTPS.
    * Para que isso funcione, um único componente (programa) em execução no servidor, ouvindo no endereço IP público, deve ter todos os certificados HTTPS no servidor.
* Depois de obter uma conexão segura, o protocolo de comunicação ainda é HTTP.

    * Painel de controle principal com criação e edição de usuário.
    * Edição do próprio usuário.
    * **Vuex**.
    * **Vue-router**.
    * **Vuetify** para belos componentes _material design_.
    * **TypeScript**.
    * Servidor Docker baseado em **Nginx** (configurado para rodar "lindamente" com Vue-router).

                    "schema": {
                        "$ref": "#/components/schemas/Message"
                    }
                }
            }
        },
        "200": {
            "description": "Successful Response",
            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/Item"
                    }
                }

    But this example is still valid and it shows how to interact with the internal components.

We can also use this same approach to access the request body in an exception handler.

All we need to do is handle the request inside a `try`/`except` block:

```Python hl_lines="13  15"

## Import Couchbase components

For now, don't pay attention to the rest, only the imports:

```Python hl_lines="3-5"
{!../../../docs_src/nosql_databases/tutorial001.py!}
```

## Define a constant to use as a "document type"

- 🚀 [React](https://react.dev) for the frontend.
    - 💃 Using TypeScript, hooks, Vite, and other parts of a modern frontend stack.
    - 🎨 [Chakra UI](https://chakra-ui.com) for the frontend components.
    - 🤖 An automatically generated frontend client.
    - 🦇 Dark mode support.
- 🐋 [Docker Compose](https://www.docker.com) for development and production.
- 🔒 Secure password hashing by default.

Plus all the security features from Starlette (including **session cookies**).

All built as reusable tools and components that are easy to integrate with your systems, data stores, relational and NoSQL databases, etc.

### Dependency Injection

FastAPI includes an extremely easy to use, but extremely powerful <abbr title='also known as "components", "resources", "services", "providers"'><strong>Dependency Injection</strong></abbr> system.

# 🔗

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

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

## ⚫️❔ "🔗 💉"

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

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

👉 📶 ⚠ 🕐❔ 👆 💪: