# CORS (Cross-Origin Resource Sharing)

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">Понятие CORS или "Cross-Origin Resource Sharing"</a> относится к ситуациям, при которых запущенный в браузере фронтенд содержит JavaScript-код, который взаимодействует с бэкендом, находящимся на другом "источнике" ("origin").

## Источник

There are several alternatives, including:

* <a href="https://www.uvicorn.org/" class="external-link" target="_blank">Uvicorn</a>: a high performance ASGI server.
* <a href="https://hypercorn.readthedocs.io/" class="external-link" target="_blank">Hypercorn</a>: an ASGI server compatible with HTTP/2 and Trio among other features.

Hay varias alternativas, incluyendo:

* <a href="https://www.uvicorn.org/" class="external-link" target="_blank">Uvicorn</a>: un servidor ASGI de alto rendimiento.
* <a href="https://hypercorn.readthedocs.io/" class="external-link" target="_blank">Hypercorn</a>: un servidor ASGI compatible con HTTP/2 y Trio entre otras funcionalidades.

{* ../../docs_src/python_types/tutorial010.py hl[6] *}


Ve yine bütün editör desteğini alırsınız:

<img src="/img/python-types/image06.png">

## Pydantic modelleri

<a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> veri doğrulaması yapmak için bir Python kütüphanesidir.

Verilerin "biçimini" niteliklere sahip sınıflar olarak düzenlersiniz.

Например, у вас есть файл `main.py`:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

Второй аргумент <a href=«https://docs.python.org/3.8/library/os.html#os.getenv» class=«external-link» target=«_blank»>`os.getenv()`</a> - это возвращаемое по умолчанию значение.

* <a href="https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.1.0.md#parameter-object" class="external-link" target="_blank">`Parameter Object` (in the specification)</a> that was used by FastAPI's:
    * `Path()`
    * `Query()`
    * `Header()`
    * `Cookie()`

      return false;
    }
  });

  $(".table tr[data-href]").each(function() {
    $(this)
      .css("cursor", "pointer")
      .hover(
        function() {
          $(this).addClass("active");
        },
        function() {
          $(this).removeClass("active");
        }
      )
      .click(function() {
        document.location = $(this).attr("data-href");
      });
  });

これをサポートするためにPydantic自体にもいくつかの変更がありました。

上記のスクリーンショットは<a href="https://code.visualstudio.com" class="external-link" target="_blank">Visual Studio Code</a>を撮ったものです。

しかし、<a href="https://www.jetbrains.com/pycharm/" class="external-link" target="_blank">PyCharm</a>やほとんどのPythonエディタでも同様なエディターサポートを受けられます:

<img src="/img/tutorial/body/image05.png">

/// tip | 豆知識

		n.lockMap[resource].ref--
		if n.lockMap[resource].ref < 0 {
			logger.CriticalIf(GlobalContext, errors.New("resource reference count was lower than 0"))
		}
		if n.lockMap[resource].ref == 0 {
			// Remove from the map if there are no more references.
			delete(n.lockMap, resource)
		}
		n.lockMapMutex.Unlock()
	}

	return
}

// Unlock the namespace resource.

                                            <c:forEach var="data" varStatus="s" items="${roleItems}">
                                                <tr
                                                        data-href="${contextPath}/admin/role/details/4/${f:u(data.id)}">
                                                    <td>${f:h(data.name)}</td>
                                                </tr>