/**
     * The name of the tag with a maximum length of 100 characters.
     */
    @Required
    @Size(max = 100)
    public String name;

    /**
     * A map containing additional tag metadata as key-value pairs.
     */
    public Map<String, String> tags = new HashMap<>();

    /**
     * Default constructor for TagForm.
     */
    public TagForm() {
        // Default constructor
    }

map[desc:CMYK colors:[cyan magenta yellow black]]
```

likewise, increasing depth level to `3` yields:
```
red
green
blue
cyan
magenta
yellow
black
```

optionally, kev:value pairs can be emitted as an individual struct:
```go
decoder := jstream.NewDecoder(f, 2).EmitKV() // enable KV streaming at a depth level of 2
```

```
jstream.KV{desc RGB}
jstream.KV{colors [red green blue]}

 * @since 3.0.2
 */
public interface EventSpy {
    /**
     * Context
     */
    interface Context {

        /**
         * Gets key-value pairs providing information about the Maven runtime.
         *
         * @return The key-value pairs, never {@code null}.
         */
        Map<String, Object> getData();
    }

    /**
     * Initializes the spy.
     *

app = FastAPI()


class Invoice(BaseModel):
    id: str
    title: Union[str, None] = None
    customer: str
    total: float


class InvoiceEvent(BaseModel):
    description: str
    paid: bool


class InvoiceEventReceived(BaseModel):
    ok: bool


invoices_callback_router = APIRouter()


@invoices_callback_router.post(

	}

	iv := DB.Table(`table_invoices`).Select(`seller, SUM(total) as total, SUM(paid) as paid, SUM(balance) as balance`).Group(`seller`)
	stmt = dryDB.Table(`table_employees`).Select(`id, name, iv.total, iv.paid, iv.balance`).Joins(`LEFT JOIN (?) AS iv ON iv.seller = table_employees.id`, iv).Scan(&user).Statement

 * This extractor provides better structured data extraction compared to Tika's generic text extraction.
 *
 * <p>Features:
 * <ul>
 *   <li>Structured text extraction with key-value pairs</li>
 *   <li>Top-level field extraction as metadata</li>
 *   <li>Nested structure flattening with configurable depth</li>
 *   <li>Array element extraction</li>
 *   <li>Configurable field separator and array formatting</li>

{* ../../docs_src/templates/tutorial001_py39.py hl[4,11,15:18] *}

/// note

Before FastAPI 0.108.0, Starlette 0.29.0, the `name` was the first parameter.

Also, before that, in previous versions, the `request` object was passed as part of the key-value pairs in the context for Jinja2.

///

/// tip

     *
     * @param paramMap the data store parameters containing configuration and metadata
     * @param dataMap the document data to be indexed as key-value pairs
     */
    void store(DataStoreParams paramMap, Map<String, Object> dataMap);

    /**
     * Returns the total number of documents processed by this callback.
     *
     * @return the document count
     */

## 存档回调

实际的回调代码高度依赖于您自己的 API 应用。

并且可能每个应用都各不相同。

回调代码可能只有一两行，比如：

```Python
callback_url = "https://example.com/api/v1/invoices/events/"
requests.post(callback_url, json={"description": "Invoice paid", "paid": True})
```

但回调最重要的部分可能是，根据 API 要发送给回调请求体的数据等内容，确保您的 API 用户（外部开发者）正确地实现*外部 API*。

因此，我们下一步要做的就是添加代码，为从 API 接收回调的*外部 API*存档。

这部分文档在 `/docs` 下的 Swagger API 文档中显示，并且会告诉外部开发者如何构建*外部 API*。

   *
   * @param capacity the capacity of this queue
   * @param fair if {@code true} then queue accesses for threads blocked on insertion or removal,
   *     are processed in FIFO order; if {@code false} the access order is unspecified.
   * @throws IllegalArgumentException if {@code capacity} is less than 1
   */
  public MonitorBasedArrayBlockingQueue(int capacity, boolean fair) {
    if (capacity <= 0) throw new IllegalArgumentException();