```

默认情况下，这个 `CORSMiddleware` 实现所使用的默认参数较为保守，所以你需要显式地启用特定的源、方法或者 headers，以便浏览器能够在跨域上下文中使用它们。

支持以下参数：

* `allow_origins` - 一个允许跨域请求的源列表。例如 `['https://example.org', 'https://www.example.org']`。你可以使用 `['*']` 允许任何源。
* `allow_origin_regex` - 一个正则表达式字符串，匹配的源允许跨域请求。例如 `'https://.*\.example\.org'`。
* `allow_methods` - 一个允许跨域请求的 HTTP 方法列表。默认为 `['GET']`。你可以使用 `['*']` 来允许所有标准方法。

 * RuntimeException}.
 *
 * <p>Here's an example that tests a {@code finalize} method:
 *
 * <pre>{@code
 * final CountDownLatch latch = new CountDownLatch(1);
 * Object x = new MyClass() {
 *   ...
 *   protected void finalize() { latch.countDown(); ... }
 * };
 * x = null;  // Hint to the JIT that x is stack-unreachable
 * GcFinalization.await(latch);
 * }</pre>
 *
 * <p>Here's an example that uses a user-defined finalization predicate:

	Porque estamos usando uma URL relativa, se sua API estava localizada em `https://example.com/`, então irá referir-se à `https://example.com/token`. Mas se sua API estava localizada em `https://example.com/api/v1/`, então irá referir-se à `https://example.com/api/v1/token`.

A GODEBUG setting is a `key=value` pair
that controls the execution of certain parts of a Go program.
The environment variable `GODEBUG`
can hold a comma-separated list of these settings.
For example, if a Go program is running in an environment that contains

	GODEBUG=http2client=0,http2server=0

then that Go program will disable the use of HTTP/2 by default in both
the HTTP client and the HTTP server.

Activating a virtual environment also changes a couple of other things, but this is one of the most important things it does.

## Checking a Virtual Environment

When you check if a virtual environment is active, for example with:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

As all these methods are `async` methods, you need to "await" them.

For example, inside of an `async` *path operation function* you can get the contents with:

```Python
contents = await myfile.read()
```

If you are inside of a normal `def` *path operation function*, you can access the `UploadFile.file` directly, for example:

```Python
contents = myfile.file.read()
```

 * the return type of the method is GWT compatible. It's useful to indicate that an instance created
 * by factory methods has a GWT serializable type. In the following example,
 *
 * <pre>
 * {@literal @}GwtCompatible
 * class Lists {
 *   ...
 *   {@literal @}GwtCompatible(serializable = true)
 *   {@literal static <E> List<E>} newArrayList(E... elements) {
 *     ...
 *   }

        "username": "johndoe",
        "full_name": "John Doe",
        "email": "johndoe@example.com",
        "hashed_password": "$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW",
        "disabled": False,
    },
    "alice": {
        "username": "alice",
        "full_name": "Alice Chains",
        "email": "alicechains@example.com",
        "hashed_password": "$2b$12$gSvqqUPvlXP2tfVFaWK1Be7DlH.PKZbv5H8KnzzVgXXbVxpva.pFm",

Поскольку мы используем относительный URL, если ваш API расположен по адресу `https://example.com/`, то он будет ссылаться на `https://example.com/token`. Если же ваш API расположен по адресу `https://example.com/api/v1/`, то он будет ссылаться на `https://example.com/api/v1/token`.

policy grants access to buckets with name starting with example. ## In addition, grants objects read permissions on buckets starting with example. # - name: readonlyexamplepolic # statements: # - resources: # - 'arn:aws:s3:::example*/*' # actions: # - "s3:GetObject" # - resources: # - 'arn:aws:s3:::example*' # actions: # - "s3:GetBucketLocation" # - "s3:ListBucket" # - "s3:ListBucketMultipartU" ## conditionsexample policy creates all access to example bucket with aws:username="johndoe" and source ip range...