您能否给我展示一个使用范围请求的HTTP会话示例,即请求和响应头部是什么?
Accept-Ranges
指示服务器支持范围请求头。GET /BigBuckBunny_320x180.mp4
Cache-Control: max-age=0
Connection: keep-alive
Accept-Language: en-GB,en-US,en
Host: localhost:8080
Range:
Accept: text/html,application/xhtml+xml,application/xml,*/*
User-Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.7 ...
Accept-Encoding: gzip,deflate,sdch
Accept-Charset: ISO-8859-1,utf-8,*
200 OK
Content-Type: video/mp4
Connection: keep-alive
Last-Modified: Wed,14 Dec 2011 15:50:59 GMT
ETag: A023EF02BD589BC472A2D6774EAE3C58
Transfer-Encoding:
Content-Length: 64657027
Accept-Ranges: bytes
Server: Brisket/1.0.1
Date: Wed,14 Dec 2011 16:11:24 GMT
检测到先前响应中的范围标头 - 后续请求使用开放式范围以确认支持。响应返回206状态和Content-Range
标头,指示响应正文中存在的字节:
GET /BigBuckBunny_320x180.mp4
Connection: keep-alive
Accept-Language: en-GB,en-US,en
Host: localhost:8080
Range: bytes=0-
Accept: */*
User-Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.7 ...
Referer: http://localhost:8080/BigBuckBunny_320x180.mp4
Accept-Encoding: identity
Accept-Charset: ISO-8859-1,utf-8,*
206 Partial Content
Content-Type: video/mp4
Connection: keep-alive
Last-Modified: Wed,14 Dec 2011 15:50:59 GMT
ETag: A023EF02BD589BC472A2D6774EAE3C58
Transfer-Encoding:
Content-Length: 64657027
Accept-Ranges: bytes
Server: Brisket/1.0.1
Date: Wed,14 Dec 2011 16:11:25 GMT
Content-Range: bytes 0-64657026/64657027
用来捕获文件结尾的后续范围请求(可能是为了捕获尾部元数据):
GET /BigBuckBunny_320x180.mp4
Connection: keep-alive
Accept-Language: en-GB,en-US,en
Host: localhost:8080
Range: bytes=64312833-64657026
Accept: */*
If-Range: A023EF02BD589BC472A2D6774EAE3C58
User-Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.7 ...
Referer: http://localhost:8080/BigBuckBunny_320x180.mp4
Accept-Encoding: identity
Accept-Charset: ISO-8859-1,utf-8,*
206 Partial Content
Content-Type: video/mp4
Connection: keep-alive
Last-Modified: Wed,14 Dec 2011 15:50:59 GMT
ETag: A023EF02BD589BC472A2D6774EAE3C58
Transfer-Encoding:
Content-Length: 344194
Accept-Ranges: bytes
Server: Brisket/1.0.1
Date: Wed,14 Dec 2011 16:11:25 GMT
Content-Range: bytes 64312833-64657026/64657027
用户在视频进度条下载范围之外点击 - 会发出范围请求,以从所选位置开始播放:
GET /BigBuckBunny_320x180.mp4
Connection: keep-alive
Accept-Language: en-GB,en-US,en
Host: localhost:8080
Range: bytes=1073152-64313343
Accept: */*
If-Range: A023EF02BD589BC472A2D6774EAE3C58
User-Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.7 ...
Referer: http://localhost:8080/BigBuckBunny_320x180.mp4
Accept-Encoding: identity
Accept-Charset: ISO-8859-1,utf-8,*
206 Partial Content
Content-Type: video/mp4
Connection: keep-alive
Last-Modified: Wed,14 Dec 2011 15:50:59 GMT
ETag: A023EF02BD589BC472A2D6774EAE3C58
Transfer-Encoding:
Content-Length: 63240192
Accept-Ranges: bytes
Server: Brisket/1.0.1
Date: Wed,14 Dec 2011 16:11:25 GMT
Content-Range: bytes 1073152-64313343/64657027
Accept-Ranges: bytes
标头告诉客户端“我接受范围请求”,但它还发送资源的内容长度,以便客户端可以进行带有上限的范围请求。就我所知,客户端消息中没有任何要求这样做 - 服务器可以选择响应“这是整个资源”或“我接受范围请求” - 这就是 Accept-Ranges
标头的存在。那就是我的理解。 - Simon Whitehead