// error returned in IAM subsystem when groups doesn't exist.
var errNoSuchGroup = errors.New("Specified group does not exist")

// error returned in IAM subsystem when a policy attach/detach request has no
// net effect, i.e. it is already applied.
var errNoPolicyToAttachOrDetach = errors.New("Specified policy update has no net effect")

// error returned in IAM subsystem when a non-empty group needs to be
// deleted.

	if string(b) != expected {
		t.Errorf("AppendFile() failed, expected: %s, got %s", expected, string(b))
	}
}

func TestSkipReader(t *testing.T) {
	testCases := []struct {
		src      io.Reader
		skipLen  int64
		expected string
	}{
		{bytes.NewBuffer([]byte("")), 0, ""},
		{bytes.NewBuffer([]byte("")), 1, ""},
		{bytes.NewBuffer([]byte("abc")), 0, "abc"},
		{bytes.NewBuffer([]byte("abc")), 1, "bc"},

这里使用的也是之前创建的 OAuth2 方案，并把它声明为依赖项：`oauth2_scheme`。

该依赖项函数本身不需要作用域，因此，可以使用 `Depends` 和 `oauth2_scheme`。不需要指定安全作用域时，不必使用 `Security`。

此处还声明了从 `fastapi.security` 导入的 `SecurityScopes` 类型的特殊参数。

`SecuriScopes` 类与 `Request` 类似（`Request` 用于直接提取请求对象）。

{* ../../docs_src/security/tutorial005.py hl[8,105] *}

## 使用 `scopes`

参数 `security_scopes` 的类型是 `SecurityScopes`。

它的属性 `scopes`  是作用域列表，所有依赖项都把它作为子依赖项。也就是说所有**依赖**……这听起来有些绕，后文会有解释。

sequenceDiagram
    participant Client
    participant Proxy as Proxy/Load Balancer
    participant Server as FastAPI Server

    Client->>Proxy: HTTPS Request<br/>Host: mysuperapp.com<br/>Path: /items

    Note over Proxy: Proxy adds forwarded headers

    Proxy->>Server: HTTP Request<br/>X-Forwarded-For: [client IP]<br/>X-Forwarded-Proto: https<br/>X-Forwarded-Host: mysuperapp.com<br/>Path: /items

    "foo",
    "bar"
  ]
}
```

/// tip

To declare a query parameter with a type of `list`, like in the example above, you need to explicitly use `Query`, otherwise it would be interpreted as a request body.

///

The interactive API docs will update accordingly, to allow multiple values:

<img src="/img/tutorial/query-params-str-validations/image02.png">

```
KEY:
etcd  federate multiple clusters for IAM and Bucket DNS

ARGS:

    // Search Execute
    //

    /**
     * Performs bulk document operations (index multiple documents).
     * Validates document fields and adds default values where necessary.
     *
     * @param body the bulk request body containing documents to process
     * @return JSON response with bulk operation results
     */
    // PUT /api/admin/documents/bulk
    @Execute
    public JsonResponse<ApiResult> put$bulk(final BulkBody body) {

                                    </div>
                                </div>
                                <c:set var="pager" value="${charMappingPager}"
                                       scope="request"/>
                                <div class="row">
                                    <div class="col-sm-2">
                                        <la:message key="labels.pagination_page_guide_msg"

import static java.util.Objects.requireNonNull;

/**
 * Collects settings that control the building of effective settings.
 */
@Experimental
@Immutable
public interface SettingsBuilderRequest extends Request<ProtoSession> {

    /**
     * Gets the installation settings source.
     *
     * @return the installation settings source or {@code null} if none
     */
    @Nonnull

	file, err := os.Open(mountFilePath)
	if err != nil {
		return nil, err
	}
	defer file.Close()
	return parseMountFrom(file)
}

func parseMountFrom(file io.Reader) (mountInfos, error) {
	mounts := mountInfos{}
	scanner := bufio.NewReader(file)
	for {
		line, err := scanner.ReadString('\n')
		if err == io.EOF {
			break
		}

		fields := strings.Fields(line)