HTTP头信息

一.概述

https://en.wikipedia.org/wiki/List_of_HTTP_header_fields?spm=5176.100239.blogcont44672.9.jvjKM8

1.请求报文

HTTP 请求报文由请求行、请求头部、空行 和 请求包体 4 个部分组成，如下图所示：

2.响应报文

HTTP 响应报文由状态行、响应头部、空行 和 响应包体 4 个部分组成，如下图所示：

二.请求字段

Header field nameDescriptionExampleStatusAcceptContent-Types that are acceptable for the response. See Content negotiation.Accept: text/plainPermanentAccept-CharsetCharacter sets that are acceptable.Accept-Charset: utf-8PermanentAccept-DatetimeAcceptable version in time.Accept-Datetime: Thu, 31 May 2007 20:35:00 GMTProvisionalAccept-EncodingList of acceptable encodings. See HTTP compression.Accept-Encoding: gzip, deflatePermanentAccept-LanguageList of acceptable human languages for response. See Content negotiation.Accept-Language: en-USPermanentAuthorizationAuthentication credentials for HTTP authentication.Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==PermanentCache-ControlUsed to specify directives that must be obeyed by all caching mechanisms along the request-response chain.Cache-Control: no-cachePermanentConnectionControl options for the current connection and list of hop-by-hop request fields.^[7]

Must not be used with HTTP/2.^[8]

Connection: keep-alive

Connection: Upgrade

PermanentContent-LengthThe length of the request body in octets (8-bit bytes).Content-Length: 348PermanentContent-MD5A Base64-encoded binary MD5 sum of the content of the request body.Content-MD5: Q2hlY2sgSW50ZWdyaXR5IQ==Obsolete^[9]Content-TypeThe MIME type of the body of the request (used with POST and PUT requests).Content-Type: application/x-www-form-urlencodedPermanentCookieAn HTTP cookie previously sent by the server with Set-Cookie (below).Cookie: $Version=1; Skin=new;Permanent: standardDateThe date and time that the message was originated (in "HTTP-date" format as defined by RFC 7231 Date/Time Formats).Date: Tue, 15 Nov 1994 08:12:31 GMTPermanentExpectIndicates that particular server behaviors are required by the client.Expect: 100-continuePermanentForwardedDisclose original information of a client connecting to a web server through an HTTP proxy.^[10]Forwarded: for=192.0.2.60;proto=http;by=203.0.113.43Forwarded: for=192.0.2.43, for=198.51.100.17PermanentFromThe email address of the user making the request.From: [e-mail] domain name of the server (for virtual hosting), and the TCP port number on which the server is listening. The port number may be omitted if the port is the standard port for the service requested.

Mandatory since HTTP/1.1.^[11] If the request is generated directly in HTTP/2, it should not be used.^[12]

Host: en.wikipedia.org:8080

Host: en.wikipedia.org

PermanentIf-MatchOnly perform the action if the client supplied entity matches the same entity on the server. This is mainly for methods like PUT to only update a resource if it has not been modified since the user last updated it.If-Match: "737060cd8c284d8af7ad3082f209582d"PermanentIf-Modified-SinceAllows a 304 Not Modified to be returned if content is unchanged.If-Modified-Since: Sat, 29 Oct 1994 19:43:31 GMTPermanentIf-None-MatchAllows a 304 Not Modified to be returned if content is unchanged, see HTTP ETag.If-None-Match: "737060cd8c284d8af7ad3082f209582d"PermanentIf-RangeIf the entity is unchanged, send me the part(s) that I am missing; otherwise, send me the entire new entity.If-Range: "737060cd8c284d8af7ad3082f209582d"PermanentIf-Unmodified-SinceOnly send the response if the entity has not been modified since a specific time.If-Unmodified-Since: Sat, 29 Oct 1994 19:43:31 GMTPermanentMax-ForwardsLimit the number of times the message can be forwarded through proxies or gateways.Max-Forwards: 10PermanentOriginInitiates a request for cross-origin resource sharing (asks server for an 'Access-Control-Allow-Origin' response field).Origin: http://www.example-social-network.comPermanent: standardPragmaImplementation-specific fields that may have various effects anywhere along the request-response chain.Pragma: no-cachePermanentProxy-AuthorizationAuthorization credentials for connecting to a proxy.Proxy-Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==PermanentRangeRequest only part of an entity. Bytes are numbered from 0. See Byte serving.Range: bytes=500-999PermanentReferer [sic]This is the address of the previous web page from which a link to the currently requested page was followed. (The word “referrer” has been misspelled in the RFC as well as in most implementations to the point that it has become standard usage and is considered correct terminology)Referer: http://en.wikipedia.org/wiki/Main_PagePermanentTEThe transfer encodings the user agent is willing to accept: the same values as for the response header field Transfer-Encoding can be used, plus the "trailers" value (related to the "chunked" transfer method) to notify the server it expects to receive additional fields in the trailer after the last, zero-sized, chunk.

Only trailers is supported in HTTP/2.^[8]

TE: trailers, deflatePermanentUpgradeAsk the server to upgrade to another protocol.

Must not be used to upgrade to HTTP/2.^[8]

Upgrade: HTTPS/1.3, IRC/6.9, RTA/x11, websocketPermanentUser-AgentThe user agent string of the user agent.User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20100101 Firefox/12.0PermanentViaInforms the server of proxies through which the request was sent.Via: 1.0 fred, 1.1 example.com (Apache/1.1)PermanentWarningA general warning about possible problems with the entity body.Warning: 199 Miscellaneous warningPermanent

三.响应字段

Field nameDescriptionExampleStatusAccept-Patch^[32]Specifies which patch document formats this server supportsAccept-Patch: text/example;charset=utf-8PermanentAccept-RangesWhat partial content range types this server supports via byte servingAccept-Ranges: bytesPermanentAccess-Control-Allow-OriginSpecifying which web sites can participate in cross-origin resource sharingAccess-Control-Allow-Origin: *ProvisionalAgeThe age the object has been in a proxy cache in secondsAge: 12PermanentAllowValid methods for a specified resource. To be used for a 405 Method not allowedAllow: GET, HEADPermanentAlt-Svc^[33]A server uses "Alt-Svc" header (meaning Alternative Services) to indicate that its resources can also be accessed at a different network location (host or port) or using a different protocol

When using HTTP/2, servers should instead send an ALTSVC frame. ^[34]

Alt-Svc: http/1.1="http2.example.com:8001"; ma=7200PermanentCache-ControlTells all caching mechanisms from server to client whether they may cache this object. It is measured in secondsCache-Control: max-age=3600PermanentConnectionControl options for the current connection and list of hop-by-hop response fields.^[7]

Must not be used with HTTP/2.^[8]

Connection: closePermanentContent-Disposition^[35]An opportunity to raise a "File Download" dialogue box for a known MIME type with binary format or suggest a filename for dynamic content. Quotes are necessary with special characters.Content-Disposition: attachment; filename="fname.ext"PermanentContent-EncodingThe type of encoding used on the data. See HTTP compression.Content-Encoding: gzipPermanentContent-LanguageThe natural language or languages of the intended audience for the enclosed content^[36]Content-Language: daPermanentContent-LengthThe length of the response body in octets (8-bit bytes)Content-Length: 348PermanentContent-LocationAn alternate location for the returned dataContent-Location: /index.htmPermanentContent-MD5A Base64-encoded binary MD5 sum of the content of the responseContent-MD5: Q2hlY2sgSW50ZWdyaXR5IQ==Obsolete^[9]Content-RangeWhere in a full body message this partial message belongsContent-Range: bytes 21010-47021/47022PermanentContent-TypeThe MIME type of this contentContent-Type: text/html; charset=utf-8PermanentDateThe date and time that the message was sent (in "HTTP-date" format as defined by RFC 7231) ^[37]Date: Tue, 15 Nov 1994 08:12:31 GMTPermanentETagAn identifier for a specific version of a resource, often amessage digestETag: "737060cd8c284d8af7ad3082f209582d"PermanentExpiresGives the date/time after which the response is considered stale (in "HTTP-date" format as defined by RFC 7231)Expires: Thu, 01 Dec 1994 16:00:00 GMTPermanent: standardLast-ModifiedThe last modified date for the requested object (in "HTTP-date" format as defined by RFC 7231)Last-Modified: Tue, 15 Nov 1994 12:45:26 GMTPermanentLinkUsed to express a typed relationship with another resource, where the relation type is defined by RFC 5988Link: </feed>; rel="alternate"^[38]PermanentLocationUsed in redirection, or when a new resource has been created.Location: http://www.w3.org/pub/WWW/People.htmlPermanentP3PThis field is supposed to set P3P policy, in the form ofP3P:CP="your_compact_policy". However, P3P did not take off,^[39] most browsers have never fully implemented it, a lot of websites set this field with fake policy text, that was enough to fool browsers the existence of P3P policy and grant permissions for third party cookies.P3P: CP="This is not a P3P policy! See http://www.google.com/support/accounts/bin/answer.py?hl=en&answer=151657 for more info."PermanentPragmaImplementation-specific fields that may have various effects anywhere along the request-response chain.Pragma: no-cachePermanentProxy-AuthenticateRequest authentication to access the proxy.Proxy-Authenticate: BasicPermanentPublic-Key-Pins^[40]HTTP Public Key Pinning, announces hash of website's authenticTLS certificatePublic-Key-Pins: max-age=2592000; pin-sha256="E9CZ9INDbd+2eRQozYqqbQ2yXLVKB9+xcprMF+44U1g=";PermanentRefreshUsed in redirection, or when a new resource has been created. This refresh redirects after 5 seconds.Refresh: 5; url=http://www.w3.org/pub/WWW/People.htmlProprietary and non-standard: a header extension introduced by Netscape and supported by most web browsers.Retry-AfterIf an entity is temporarily unavailable, this instructs the client to try again later. Value could be a specified period of time (in seconds) or a HTTP-date.^[41]

• Example 1: Retry-After: 120
• Example 2: Retry-After: Fri, 07 Nov 2014 23:59:59 GMT

Permanent

ServerA name for the serverServer: Apache/2.4.1 (Unix)PermanentSet-CookieAn HTTP cookieSet-Cookie: UserID=JohnDoe; Max-Age=3600; Version=1Permanent: standardStrict-Transport-SecurityA HSTS Policy informing the HTTP client how long to cache the HTTPS only policy and whether this applies to subdomains.Strict-Transport-Security: max-age=16070400; includeSubDomainsPermanent: standardTkTracking Status header, value suggested to be sent in response to a DNT(do-not-track), possible values:

"!" — under construction"?" — dynamic"G" — gateway to multiple parties"N" — not tracking"T" — tracking"C" — tracking with consent"P" — tracking only if consented"D" — disregarding DNT"U" — updated

Tk: ?PermanentTrailerThe Trailer general field value indicates that the given set of header fields is present in the trailer of a message encoded with chunked transfer coding.Trailer: Max-ForwardsPermanentTransfer-EncodingThe form of encoding used to safely transfer the entity to the user. Currently defined methods are: chunked, compress, deflate, gzip, identity.

Must not be used with HTTP/2.^[8]

Transfer-Encoding: chunkedPermanentUpgradeAsk the client to upgrade to another protocol.

Must not be used to upgrade to HTTP/2^[8]

Upgrade: HTTPS/1.3, IRC/6.9, RTA/x11, websocketPermanentVaryTells downstream proxies how to match future request headers to decide whether the cached response can be used rather than requesting a fresh one from the origin server.

• Example 1: Vary: *
• Example 2: Vary: Accept-Language

PermanentViaInforms the client of proxies through which the response was sent.Via: 1.0 fred, 1.1 example.com (Apache/1.1)PermanentWarningA general warning about possible problems with the entity body.Warning: 199 Miscellaneous warningPermanentWWW-AuthenticateIndicates the authentication scheme that should be used to access the requested entity.WWW-Authenticate: BasicPermanentX-Frame-Options^[42]Clickjacking protection: deny - no rendering within a frame,sameorigin - no rendering if origin mismatch, allow-from - allow from specified location, allowall - non-standard, allow from any locationX-Frame-Options: denyObsolete^[43]

Field nameDescriptionExampleStatusAccept-Patch^[32]Specifies which patch document formats this server supportsAccept-Patch: text/example;charset=utf-8PermanentAccept-RangesWhat partial content range types this server supports via byte servingAccept-Ranges: bytesPermanentAccess-Control-Allow-OriginSpecifying which web sites can participate in cross-origin resource sharingAccess-Control-Allow-Origin: *ProvisionalAgeThe age the object has been in a proxy cache in secondsAge: 12PermanentAllowValid methods for a specified resource. To be used for a 405 Method not allowedAllow: GET, HEADPermanentAlt-Svc^[33]A server uses "Alt-Svc" header (meaning Alternative Services) to indicate that its resources can also be accessed at a different network location (host or port) or using a different protocol

When using HTTP/2, servers should instead send an ALTSVC frame. ^[34]

Alt-Svc: http/1.1="http2.example.com:8001"; ma=7200PermanentCache-ControlTells all caching mechanisms from server to client whether they may cache this object. It is measured in secondsCache-Control: max-age=3600PermanentConnectionControl options for the current connection and list of hop-by-hop response fields.^[7]

Must not be used with HTTP/2.^[8]

Connection: closePermanentContent-Disposition^[35]An opportunity to raise a "File Download" dialogue box for a known MIME type with binary format or suggest a filename for dynamic content. Quotes are necessary with special characters.Content-Disposition: attachment; filename="fname.ext"PermanentContent-EncodingThe type of encoding used on the data. See HTTP compression.Content-Encoding: gzipPermanentContent-LanguageThe natural language or languages of the intended audience for the enclosed content^[36]Content-Language: daPermanentContent-LengthThe length of the response body in octets (8-bit bytes)Content-Length: 348PermanentContent-LocationAn alternate location for the returned dataContent-Location: /index.htmPermanentContent-MD5A Base64-encoded binary MD5 sum of the content of the responseContent-MD5: Q2hlY2sgSW50ZWdyaXR5IQ==Obsolete^[9]Content-RangeWhere in a full body message this partial message belongsContent-Range: bytes 21010-47021/47022PermanentContent-TypeThe MIME type of this contentContent-Type: text/html; charset=utf-8PermanentDateThe date and time that the message was sent (in "HTTP-date" format as defined by RFC 7231) ^[37]Date: Tue, 15 Nov 1994 08:12:31 GMTPermanentETagAn identifier for a specific version of a resource, often amessage digestETag: "737060cd8c284d8af7ad3082f209582d"PermanentExpiresGives the date/time after which the response is considered stale (in "HTTP-date" format as defined by RFC 7231)Expires: Thu, 01 Dec 1994 16:00:00 GMTPermanent: standardLast-ModifiedThe last modified date for the requested object (in "HTTP-date" format as defined by RFC 7231)Last-Modified: Tue, 15 Nov 1994 12:45:26 GMTPermanentLinkUsed to express a typed relationship with another resource, where the relation type is defined by RFC 5988Link: </feed>; rel="alternate"^[38]PermanentLocationUsed in redirection, or when a new resource has been created.Location: http://www.w3.org/pub/WWW/People.htmlPermanentP3PThis field is supposed to set P3P policy, in the form ofP3P:CP="your_compact_policy". However, P3P did not take off,^[39] most browsers have never fully implemented it, a lot of websites set this field with fake policy text, that was enough to fool browsers the existence of P3P policy and grant permissions for third party cookies.P3P: CP="This is not a P3P policy! See http://www.google.com/support/accounts/bin/answer.py?hl=en&answer=151657 for more info."PermanentPragmaImplementation-specific fields that may have various effects anywhere along the request-response chain.Pragma: no-cachePermanentProxy-AuthenticateRequest authentication to access the proxy.Proxy-Authenticate: BasicPermanentPublic-Key-Pins^[40]HTTP Public Key Pinning, announces hash of website's authenticTLS certificatePublic-Key-Pins: max-age=2592000; pin-sha256="E9CZ9INDbd+2eRQozYqqbQ2yXLVKB9+xcprMF+44U1g=";PermanentRefreshUsed in redirection, or when a new resource has been created. This refresh redirects after 5 seconds.Refresh: 5; url=http://www.w3.org/pub/WWW/People.htmlProprietary and non-standard: a header extension introduced by Netscape and supported by most web browsers.Retry-AfterIf an entity is temporarily unavailable, this instructs the client to try again later. Value could be a specified period of time (in seconds) or a HTTP-date.^[41]

• Example 1: Retry-After: 120
• Example 2: Retry-After: Fri, 07 Nov 2014 23:59:59 GMT

Permanent

ServerA name for the serverServer: Apache/2.4.1 (Unix)PermanentSet-CookieAn HTTP cookieSet-Cookie: UserID=JohnDoe; Max-Age=3600; Version=1Permanent: standardStrict-Transport-SecurityA HSTS Policy informing the HTTP client how long to cache the HTTPS only policy and whether this applies to subdomains.Strict-Transport-Security: max-age=16070400; includeSubDomainsPermanent: standardTkTracking Status header, value suggested to be sent in response to a DNT(do-not-track), possible values:

"!" — under construction"?" — dynamic"G" — gateway to multiple parties"N" — not tracking"T" — tracking"C" — tracking with consent"P" — tracking only if consented"D" — disregarding DNT"U" — updated

Tk: ?PermanentTrailerThe Trailer general field value indicates that the given set of header fields is present in the trailer of a message encoded with chunked transfer coding.Trailer: Max-ForwardsPermanentTransfer-EncodingThe form of encoding used to safely transfer the entity to the user. Currently defined methods are: chunked, compress, deflate, gzip, identity.

Must not be used with HTTP/2.^[8]

Transfer-Encoding: chunkedPermanentUpgradeAsk the client to upgrade to another protocol.

Must not be used to upgrade to HTTP/2^[8]

Upgrade: HTTPS/1.3, IRC/6.9, RTA/x11, websocketPermanentVaryTells downstream proxies how to match future request headers to decide whether the cached response can be used rather than requesting a fresh one from the origin server.

• Example 1: Vary: *
• Example 2: Vary: Accept-Language

PermanentViaInforms the client of proxies through which the response was sent.Via: 1.0 fred, 1.1 example.com (Apache/1.1)PermanentWarningA general warning about possible problems with the entity body.Warning: 199 Miscellaneous warningPermanentWWW-AuthenticateIndicates the authentication scheme that should be used to access the requested entity.WWW-Authenticate: BasicPermanentX-Frame-Options^[42]Clickjacking protection: deny - no rendering within a frame,sameorigin - no rendering if origin mismatch, allow-from - allow from specified location, allowall - non-standard, allow from any locationX-Frame-Options: denyObsolete^[43]