`Query`, `Path`, `Header` 그리고 다른 것들을 `fastapi`에서 임포트 할 때, 이들은 실제로 특별한 클래스를 반환하는 함수임을 기억하세요.

///

/// info | 정보

헤더를 선언하기 위해서 `Header`를 사용해야 합니다. 그렇지 않으면 해당 매개변수를 쿼리 매개변수로 해석하기 때문입니다.

///

## 자동 변환 { #automatic-conversion }

`Header`는 `Path`, `Query` 그리고 `Cookie`가 제공하는 것 외에 기능이 조금 더 있습니다.

대부분의 표준 헤더는 "마이너스 기호" (`-`)라고도 하는 "하이픈" 문자로 구분됩니다.

그러나 파이썬에서 `user-agent`와 같은 형태의 변수는 유효하지 않습니다.

* **Convert data**: from the request to the required type.
* **Validate data**: coming from each request:
    * Generating **automatic errors** returned to the client when the data is invalid.
* **Document** the API using OpenAPI:
    * which is then used by the automatic interactive documentation user interfaces.

 *
 * <h2>More on {@code CacheBuilder}</h2>
 *
 * {@code CacheBuilder} builds caches with any combination of the following features:
 *
 * <ul>
 *   <li>automatic loading of entries into the cache
 *   <li>least-recently-used eviction when a maximum size is exceeded (note that the cache is
 *       divided into segments, each of which does LRU internally)

 *
 * <p>Features:</p>
 * <ul>
 *   <li>Pattern-based client mapping</li>
 *   <li>Ordered client registration</li>
 *   <li>Bulk client registration</li>
 *   <li>Automatic client initialization</li>
 *   <li>Resource cleanup management</li>
 * </ul>
 *
 */
public class CrawlerClientFactory implements AutoCloseable {

	v.setString(asString)
	return err
}

// When numeric types are compared, type promotions could happen. If
// values do not have types (e.g. when reading from CSV), for
// comparison operations, automatic type conversion happens by trying
// to check if the value is a number (first an integer, then a float),
// and falling back to string.
func (v *Value) compareOp(op string, a *Value) (res bool, err error) {

import jakarta.annotation.Resource;

/**
 * API action for admin document management.
 * Provides RESTful API endpoints for bulk document operations in the Fess search engine.
 * Supports indexing multiple documents with automatic field validation and default value assignment.
 */
public class ApiAdminDocumentsAction extends FessApiAdminAction {

    // ===================================================================================
    // Constant

        AfterValidator(_check_id_no_null),
        Doc(
            """
            Optional event ID.

            The browser sends this value back as the `Last-Event-ID` header on
            automatic reconnection. **Must not contain null (`\\0`) characters.**
            """
        ),
    ] = None
    retry: Annotated[
        int | None,
        Field(ge=0),
        Doc(
            """

     * <ul>
     *   <li>Command line activation using the -P flag</li>
     *   <li>Maven settings activation in settings.xml via &lt;activeProfiles&gt;</li>
     *   <li>Automatic activation via &lt;activation&gt; conditions</li>
     *   <li>The default active profile (marked with &lt;activeByDefault&gt;true&lt;/activeByDefault&gt;)</li>
     * </ul>
     * <p>

		return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
	}

	var setSize uint64
	// Custom set drive count allows to override automatic distribution.
	// only meant if you want to further optimize drive distribution.
	if setDriveCount > 0 {
		msg := fmt.Sprintf("Invalid set drive count. Acceptable values for %d number drives are %d", commonSize, setCounts)

You will see the automatic interactive API documentation (provided by [Swagger UI](https://github.com/swagger-api/swagger-ui)):

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### Alternative API docs { #alternative-api-docs }

And now, go to [http://127.0.0.1:8000/redoc](http://127.0.0.1:8000/redoc).