direktori cari
Guides Access control CORS Authentication Browser detection using the user agent Caching Caching FAQ Compression Conditional requests Connection management in HTTP 1.x Content negotiation Content negotiation: List of default Accept values Cookies CSP Messages Overview Protocol upgrade mechanism Proxy servers and tunneling Proxy servers and tunneling: Proxy Auto-Configuration (PAC) file Public Key Pinning Range requests Redirections Resources and specifications Resources and URIs Response codes Server-Side Access Control Session Guides: Basics Basics of HTTP Choosing between www and non-www URLs Data URIs Evolution of HTTP Identifying resources on the Web MIME Types MIME types: Complete list of MIME types CSP Content-Security-Policy Content-Security-Policy-Report-Only CSP: base-uri CSP: block-all-mixed-content CSP: child-src CSP: connect-src CSP: default-src CSP: font-src CSP: form-action CSP: frame-ancestors CSP: frame-src CSP: img-src CSP: manifest-src CSP: media-src CSP: object-src CSP: plugin-types CSP: referrer CSP: report-uri CSP: require-sri-for CSP: sandbox CSP: script-src CSP: style-src CSP: upgrade-insecure-requests CSP: worker-src Headers Accept Accept-Charset Accept-Encoding Accept-Language Accept-Ranges Access-Control-Allow-Credentials Access-Control-Allow-Headers Access-Control-Allow-Methods Access-Control-Allow-Origin Access-Control-Expose-Headers Access-Control-Max-Age Access-Control-Request-Headers Access-Control-Request-Method Age Allow Authorization Cache-Control Connection Content-Disposition Content-Encoding Content-Language Content-Length Content-Location Content-Range Content-Type Cookie Cookie2 Date DNT ETag Expect Expires Forwarded From Headers Host If-Match If-Modified-Since If-None-Match If-Range If-Unmodified-Since Keep-Alive Large-Allocation Last-Modified Location Origin Pragma Proxy-Authenticate Proxy-Authorization Public-Key-Pins Public-Key-Pins-Report-Only Range Referer Referrer-Policy Retry-After Server Set-Cookie Set-Cookie2 SourceMap Strict-Transport-Security TE Tk Trailer Transfer-Encoding Upgrade-Insecure-Requests User-Agent User-Agent: Firefox Vary Via Warning WWW-Authenticate X-Content-Type-Options X-DNS-Prefetch-Control X-Forwarded-For X-Forwarded-Host X-Forwarded-Proto X-Frame-Options X-XSS-Protection Methods CONNECT DELETE GET HEAD Methods OPTIONS PATCH POST PUT Status 100 Continue 101 Switching Protocols 200 OK 201 Created 202 Accepted 203 Non-Authoritative Information 204 No Content 205 Reset Content 206 Partial Content 300 Multiple Choices 301 Moved Permanently 302 Found 303 See Other 304 Not Modified 307 Temporary Redirect 308 Permanent Redirect 400 Bad Request 401 Unauthorized 403 Forbidden 404 Not Found 405 Method Not Allowed 406 Not Acceptable 407 Proxy Authentication Required 408 Request Timeout 409 Conflict 410 Gone 411 Length Required 412 Precondition Failed 413 Payload Too Large 414 URI Too Long 415 Unsupported Media Type 416 Range Not Satisfiable 417 Expectation Failed 426 Upgrade Required 428 Precondition Required 429 Too Many Requests 431 Request Header Fields Too Large 451 Unavailable For Legal Reasons 500 Internal Server Error 501 Not Implemented 502 Bad Gateway 503 Service Unavailable 504 Gateway Timeout 505 HTTP Version Not Supported 511 Network Authentication Required Status
watak

非标准

这个功能是非标准的,不在标准轨道上。不要在面向 Web 的生产站点上使用它:它不适用于每个用户。实现之间也可能存在很大的不兼容性,并且行为在未来可能会发生变化。

Keep-Alive一般报头允许发送者提示关于如何连接,并且可以被用于设置超时时间,并且请求的最大数量。

Connection头需要被设置为“保活”这个标题有任何意义。此外,ConnectionKeep-Alive在 HTTP / 2 忽略; 连接管理由其他机制处理。

Header type

General header

Forbidden header name

no

句法

Keep-Alive: parameters

指令

_parameters_ 逗号分隔的参数列表,每个参数都包含由等号('=')分隔的标识符和值。以下标识符是可能的:

  • timeout:指示空闲连接必须保持打开的最短时间(以秒为单位)。请注意,如果在传输级别上未设置保持活动 TCP 消息,则可能会忽略超过 TCP 超时的超时。

  • max:指示在关闭它之前可以在此连接上发送的最大请求数。除非0,对于非流水线连接,此值将被忽略,因为另一个请求将在下一个响应中发送。HTTP 管道可以使用它来限制流水线。

例子

包含Keep-Alive标题的响应:

HTTP/1.1 200 OK
Connection: Keep-Alive
Content-Encoding: gzip
Content-Type: text/html; charset=utf-8Date: Thu, 11 Aug 2016 15:23:13 GMT
Keep-Alive: timeout=5, max=1000Last-Modified: Mon, 25 Jul 2016 04:32:39 GMT
Server: Apache(body)

产品规格

Specification

Title

HyperText Transport Protocol Keep-Alive Header

The Keep-Alive Header (Experimental specification)

RFC 7230, section appendix-A.1.2: Keep-Alive

Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing

浏览器兼容性

Feature

Chrome

Edge

Firefox

Internet Explorer

Opera

Safari

Basic Support

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

Feature

Android

Chrome for Android

Edge mobile

Firefox for Android

IE mobile

Opera Android

iOS Safari

Basic Support

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

请参阅

  • Connection

  • HTTP / 1.x 中的连接管理

Artikel sebelumnya: Artikel seterusnya: