# CORS (Cross-Origin Resource Sharing) { #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 { #origin }

# CORS (Cross-Origin Resource Sharing) { #cors-cross-origin-resource-sharing }

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">CORS o "Cross-Origin Resource Sharing"</a> se refiere a situaciones en las que un frontend que se ejecuta en un navegador tiene código JavaScript que se comunica con un backend, y el backend está en un "origen" diferente al frontend.

## Origen { #origin }

                                                    <li class="page-item"><la:link
                                                                                   styleClass="page-link"
                                                                                   href="prev?q=${f:u(q)}&pn=${f:u(currentPageNumber)}&num=${f:u(pageSize)}&labelTypeValue=${f:u(labelTypeValue)}">

例如：

* <a href="https://code.visualstudio.com/docs/python/environments#_select-and-activate-an-environment" class="external-link" target="_blank">VS Code</a>
* <a href="https://www.jetbrains.com/help/pycharm/creating-virtual-environment.html" class="external-link" target="_blank">PyCharm</a>

/// tip

通常你只需要在建立虛擬環境時執行此操作**一次**。

///

## 退出虛擬環境

當你完成工作後，你可以**退出**虛擬環境。

例如：

* <a href="https://code.visualstudio.com/docs/python/environments#_select-and-activate-an-environment" class="external-link" target="_blank">VS Code</a>
* <a href="https://www.jetbrains.com/help/pycharm/creating-virtual-environment.html" class="external-link" target="_blank">PyCharm</a>

/// tip

通常你只需要在创建虚拟环境时执行此操作**一次**。

///

## 退出虚拟环境

当你完成工作后，你可以**退出**虚拟环境。

 */
package org.codelibs.core.exception;

import static org.codelibs.core.collection.ArrayUtil.asArray;

import java.lang.reflect.Field;

/**
 * Exception thrown when accessing a non-{@literal static} {@link Field} without specifying an object.
 *
 * @author koichik
 */
public class FieldNotStaticRuntimeException extends ClRuntimeException {

    private static final long serialVersionUID = -7791347225750660981L;

 */
package org.codelibs.core.exception;

import static org.codelibs.core.collection.ArrayUtil.asArray;

import java.lang.reflect.Method;

/**
 * Exception thrown when accessing a non-{@literal static} {@link Method} without specifying an object.
 *
 * @author koichik
 */
public class MethodNotStaticRuntimeException extends ClRuntimeException {

    private static final long serialVersionUID = 7186052234464152208L;

 * governing permissions and limitations under the License.
 */
package org.codelibs.core.exception;

import static org.codelibs.core.collection.ArrayUtil.asArray;

/**
 * Exception that wraps {@link NoSuchFieldException}.
 *
 * @author higa
 */
public class NoSuchFieldRuntimeException extends ClRuntimeException {

    private static final long serialVersionUID = 6609175673610180338L;

    /**

/// note | 技术细节

任何一个可以与以下内容一起使用的函数：

* <a href="https://docs.python.org/3/library/contextlib.html#contextlib.contextmanager" class="external-link" target="_blank">`@contextlib.contextmanager`</a> 或者
* <a href="https://docs.python.org/3/library/contextlib.html#contextlib.asynccontextmanager" class="external-link" target="_blank">`@contextlib.asynccontextmanager`</a>

都可以作为 **FastAPI** 的依赖项。

实际上，FastAPI内部就使用了这两个装饰器。

///

Aqui veremos um exemplo usando <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a>.