Via 是一个通用首部，是由代理服务器添加的，适用于正向和反向代理，在请求和响应首部中均可出现。这个消息首部可以用来追踪消息转发情况，防止循环请求，以及识别在请求或响应传递链中消息发送者对于协议的支持能力。
| Header type | General header |
|---|---|
| Forbidden header name | yes |
语法
Via: [ <protocol-name> "/" ] <protocol-version> <host> [ ":" <port> ] or Via: [ <protocol-name> "/" ] <protocol-version> <pseudonym>
指令
- <protocol-name>
- 可选。所使用的协议名称，如 "HTTP"。
- <protocol-version>
- 所使用的协议版本号， 例如 "1.1"。
- <host> and <port>
- 公共代理的URL及端口号。
- <pseudonym>
- 内部代理的名称或别名。
示例
Via: 1.1 vegur Via: HTTP/1.1 GWA Via: 1.0 fred, 1.1 p.example.net
规范
| Specification | Title |
|---|---|
| RFC 7230, section 5.7.1: Via | Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing |
浏览器兼容性
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Via | Chrome Full support Yes | Edge Full support 12 | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support