整理 HTTP协议：头定义

HTTP头定义介绍

1 Accept 指示能够接受的返回数据的范围 request-header

语法：
Accept = "Accept" ":" #( media-range[accept-params] )
media-range = ( "*/*"
| ( type "/" "*" )
| ( type "/" subtype )
) * ( ";" parameter )
accept-params = ";" "q" "=" qvalue *( accept-extension )
accept-extension = ";" token [ "=" ( token | quoted-string ) ]
例如：Accept: */*

2 Accept-Charset 指示返回数据的字符集 request-header

Accept-Charset = "Accept-Charset" ":"
1#( ( charset | "*" )[ ";" "q" "=" qvalue ] )
Accept-Charset: iso-8859-5, unicode-1-1;q=0.8

3 Accept-Encoding 有点类是Accept request-header
Accept-Encoding = "Accept-Encoding" ":"
1#( codings [ ";" "q" "=" qvalue ] )
codings = ( content-coding | "*" )
Accept-Encoding: *

4 Accept-Language request-header
Accept-Language = "Accept-Language" ":"
1#( language-range [ ";" "q" "=" qvalue ] )
language-range = ( ( 1*8ALPHA *( "-" 1*8ALPHA ) ) | "*" )

5 Accept-Ranges 指明服务器能接受的请求资源范围 response-header
Accept-Ranges = "Accept-Ranges" ":" acceptable-ranges
acceptable-ranges = 1#range-unit | "none"
Accept-Ranges: bytes

6 Age 在第一次请求服务到下次服务器之间时间内，如果内容没有改变并且Age没有过期，
将传回缓存回发数据。response-header
Age = "Age" ":" age-value
age-value = delta-seconds

7 Allow 指示资源能被请求的形式 entity-header
Allow = "Allow" ":" #Method

Allow: GET, HEAD, PUT

8 Authorization 用户授权
Authorization = "Authorization" ":" credentials

9 Cache-Control 指定必须遵循缓存机制 general-header
Cache-Control = "Cache-Control" ":" 1#cache-directive
cache-directive = cache-request-directive
| cache-response-directive
cache-request-directive =
"no-cache"
| "no-store"
| "max-age" "=" delta-seconds
| "max-stale" [ "=" delta-seconds ]
| "min-fresh" "=" delta-seconds
| "no-transform"
| "only-if-cached"
| cache-extension
cache-response-directive =
"public"
| "private" [ "=" <"> 1#field-name <"> ]
| "no-cache" [ "=" <"> 1#field-name <"> ]
| "no-store"
| "no-transform"
| "must-revalidate"
| "proxy-revalidate"
| "max-age" "=" delta-seconds
| "s-maxage" "=" delta-seconds
| cache-extension
cache-extension = token [ "=" ( token | quoted-string ) ]

10 Connection general-header

11 Content-Encoding entity-header

12 Content-Language entity-header

13 Content-Length entity-header

14 Content-Location entity-header

15 Content-MD5 entity-header

16 Content-Range entity-header

17 Content-Type entity-header

18 Date general-header

19 ETag response-header

20 Expect request-header

21 Expires entity-header

22 From request-header

23 Host request-header

24 If-Match request-header

25 If-Modified-Since request-header

26 If-None-Match request-header

27 If-Range request-header

28 If-Unmodified-Since request-header

29 Last-Modified entity-header

30 Location response-header

31 Max-Forwards request-header

32 Pragma general-header

33 Proxy-Authenticate response-header

34 Proxy-Authorization request-header

35 Range

36 Referer request-header

37 Retry-After response-header

38 Server response-header

39 TE request-header

40 Trailer general field

41 Transfer-Encoding general-header

42 Upgrade general-header

43 User-Agent request-header
User-Agent = "User-Agent" ":" 1*( product | comment )

44 Vary

45 Via general-header

46 Warning general-header

47 WWW-Authenticate response-header