* limitations under the License.
 */
package okhttp3.internal.http2

import okio.ByteString
import okio.ByteString.Companion.encodeUtf8

/** HTTP header: the name is an ASCII string, but the value can be UTF-8. */
data class Header(
  /** Name in case-insensitive ASCII encoding. */
  @JvmField val name: ByteString,
  /** Value in UTF-8 encoding. */
  @JvmField val value: ByteString,
) {

### Checando a documentação

Você pode ver os headers necessários na interface gráfica da documentação em `/docs`:

<div class="screenshot">
<img src="/img/tutorial/header-param-models/image01.png">
</div>

### Proibindo Cabeçalhos adicionais

And as the `Response` can be used frequently to set headers and cookies, **FastAPI** also provides it at `fastapi.Response`.

///

## Custom Headers

Keep in mind that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the 'X-' prefix</a>.

```

////

/// note | "技术细节"

`Header` 是 `Path`、`Query`、`Cookie` 的**兄弟类**，都继承自共用的 `Param` 类。

注意，从 `fastapi` 导入的 `Query`、`Path`、`Header` 等对象，实际上是返回特殊类的函数。

///

/// info | "说明"

必须使用 `Header` 声明 header 参数，否则该参数会被解释为查询参数。

///

## 自动转换

`Header` 比 `Path`、`Query` 和 `Cookie` 提供了更多功能。

大部分标准请求头用**连字符**分隔，即**减号**（`-`）。

# Header-параметры

Вы можете определить параметры заголовка таким же образом, как вы определяете параметры `Query`, `Path` и `Cookie`.

## Импорт `Header`

Сперва импортируйте `Header`:

//// tab | Python 3.10+

```Python hl_lines="3"
{!> ../../docs_src/header_params/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="3"
{!> ../../docs_src/header_params/tutorial001_an_py39.py!}
```

<%@page pageEncoding="UTF-8" contentType="text/html; charset=UTF-8"%>
<la:form action="/search" method="get" styleId="searchForm"
	role="search">
	${fe:facetForm()}${fe:geoForm()}
	<header>
		<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
			<div id="content" class="container">
				<la:link styleClass="navbar-brand d-inline-flex" href="/">
					<img src="${fe:url('/images/logo-head.png')}"

<%@page pageEncoding="UTF-8" contentType="text/html; charset=UTF-8"%>
<la:form action="/search" method="get" styleId="searchForm"
	role="search">
	${fe:facetForm()}${fe:geoForm()}
	<header>
		<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
			<div id="content" class="container">
				<la:link styleClass="navbar-brand d-inline-flex" href="/">
					<img src="${fe:url('/images/logo-head.png')}"

<%@page pageEncoding="UTF-8" contentType="text/html; charset=UTF-8"%>
<nav class="main-header navbar navbar-expand navbar-dark navbar-secondary">
	<ul class="navbar-nav">
		<li class="nav-item">
			<a class="nav-link" data-widget="pushmenu" href="#">
				<em class="fas fa-bars">
				<span class="sr-only"><la:message
						key="labels.admin_toggle_navi" /></span>
			</a>
		</li>
	</ul>
	<ul class="navbar-nav ml-auto">
		<c:if test="${eoled}">

	hdr := r.opts.HeaderSize // remaining header bytes
	var tokens int           // number of tokens to request

	if hdr > 0 { // available tokens go towards header first
		if hdr < b { // all of header can be accommodated
			r.opts.HeaderSize = 0
			need = int(math.Min(float64(b-hdr), float64(need))) // use remaining tokens towards payload
			tokens = need + hdr

		} else { // part of header can be accommodated
			r.opts.HeaderSize -= b - 1

```

////

/// note | "📡 ℹ"

`Header` "👭" 🎓 `Path`, `Query` & `Cookie`. ⚫️ 😖 ⚪️➡️ 🎏 ⚠ `Param` 🎓.

✋️ 💭 👈 🕐❔ 👆 🗄 `Query`, `Path`, `Header`, & 🎏 ⚪️➡️ `fastapi`, 👈 🤙 🔢 👈 📨 🎁 🎓.

///

/// info

📣 🎚, 👆 💪 ⚙️ `Header`, ↩️ ⏪ 🔢 🔜 🔬 🔢 🔢.

///

## 🏧 🛠️

`Header` ✔️ 🐥 ➕ 🛠️ 🔛 🔝 ⚫️❔ `Path`, `Query` & `Cookie` 🚚.