## Добавление `dependencies` в *декоратор операции пути*

*Декоратор операции пути* получает необязательный аргумент `dependencies`.

Это должен быть `list` состоящий из `Depends()`:

{* ../../docs_src/dependencies/tutorial006_an_py39.py hl[19] *}

## 🚮 `dependencies` *➡ 🛠️ 👨‍🎨*

*➡ 🛠️ 👨‍🎨* 📨 📦 ❌ `dependencies`.

⚫️ 🔜 `list` `Depends()`:

{* ../../docs_src/dependencies/tutorial006.py hl[17] *}

👉 🔗 🔜 🛠️/❎ 🎏 🌌 😐 🔗. ✋️ 👫 💲 (🚥 👫 📨 🙆) 🏆 🚫 🚶‍♀️ 👆 *➡ 🛠️ 🔢*.

/// tip

👨‍🎨 ✅ ♻ 🔢 🔢, & 🎦 👫 ❌.

⚙️ 👉 `dependencies` *➡ 🛠️ 👨‍🎨* 👆 💪 ⚒ 💭 👫 🛠️ ⏪ ❎ 👨‍🎨/🏭 ❌.

* All these *path operations* will have the list of `dependencies` evaluated/executed before them.
    * If you also declare dependencies in a specific *path operation*, **they will be executed too**.
    * The router dependencies are executed first, then the [`dependencies` in the decorator](dependencies/dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, and then the normal parameter dependencies.

  dependencies:
    "@types/node" "*"

"@types/eslint-scope@^3.7.3":
  version "3.7.4"
  resolved "https://registry.yarnpkg.com/@types/eslint-scope/-/eslint-scope-3.7.4.tgz#37fc1223f0786c39627068a12e94d6e6fc61de16"
  integrity sha512-9K4zoImiZc3HlIp6AVUDE4CWYx22a+lhSZMYNpbjW04+YF0KWj4pJXnEMjdnFTiQibFFmElcsasJXDbdI/EPhA==
  dependencies:
    "@types/eslint" "*"
    "@types/estree" "*"

...👥 🎯.

* 👫 🔜 ™ ⏮️ 📇 🔖 👈 🔌 👁 🎻 `"items"`.
    * 👫 "🔖" ✴️ ⚠ 🏧 🎓 🧾 ⚙️ (⚙️ 🗄).
* 🌐 👫 🔜 🔌 🔁 `responses`.
* 🌐 👫 *➡ 🛠️* 🔜 ✔️ 📇 `dependencies` 🔬/🛠️ ⏭ 👫.
    * 🚥 👆 📣 🔗 🎯 *➡ 🛠️*, **👫 🔜 🛠️ 💁‍♂️**.
    * 📻 🔗 🛠️ 🥇, ⤴️ [`dependencies` 👨‍🎨](dependencies/dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, & ⤴️ 😐 🔢 🔗.

You can define dependencies that in turn can define dependencies themselves.

In the end, a hierarchical tree of dependencies is built, and the **Dependency Injection** system takes care of solving all these dependencies for you (and their sub-dependencies) and providing (injecting) the results at each step.

/**
 * Collects, flattens and resolves dependencies.
 */
@Experimental
public interface DependencyResolver extends Service {

    /**
     * Collects the transitive dependencies of some artifacts and builds a dependency graph for the given path scope.
     * Note that this operation is only concerned about determining the coordinates of the transitive dependencies and
     * does not actually resolve the artifact files.
     *

        /**
         * Sets the direct dependencies. If both a root dependency and direct dependencies are given in the request, the
         * direct dependencies from the request will be merged with the direct dependencies from the root dependency's
         * artifact descriptor, giving higher priority to the dependencies from the request.
         *
         * @param dependencies the direct dependencies, may be {@code null}

Also fügen wir sie in ihr eigenes `dependencies`-Modul (`app/dependencies.py`) ein.

Wir werden nun eine einfache Abhängigkeit verwenden, um einen benutzerdefinierten `X-Token`-Header zu lesen:

//// 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+

Мы поместим их в отдельный модуль `dependencies` (`app/dependencies.py`).

Теперь мы воспользуемся простой зависимостью, чтобы прочитать кастомизированный `X-Token` из заголовка:

//// 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+