HTTP request headers and Response headers explained in detail

Source: Internet
Author: User
Tags ranges

For a more detailed understanding of HTTP request headers and response headers, see the requests section below
Header explain Example
Accept Specify what types of content clients can receive Accept:text/plain, text/html
Accept-charset The set of character encodings that the browser can accept. Accept-charset:iso-8859-5
Accept-encoding Specifies that the Web server that the browser can support returns the content compression encoding type. Accept-encoding:compress, gzip
Accept-language Browser-acceptable language Accept-language:en,zh
Accept-ranges You can request one or more child range fields for a Web page entity Accept-ranges:bytes
Authorization Authorization Certificate for HTTP Authorization Authorization:basic qwxhzgrpbjpvcgvuihnlc2ftzq==
Cache-control Specify the caching mechanism that requests and responses follow Cache-control:no-cache
Connection Indicates whether a persistent connection is required. (HTTP 1.1 defaults to persistent connection) Connection:close
Cookies When an HTTP request is sent, all cookie values stored under that request domain are sent to the Web server. Cookie: $Version = 1; Skin=new;
Content-length The requested content length content-length:348
Content-type The requested MIME information corresponding to the entity content-type:application/x-www-form-urlencoded
Date Date and time the request was sent Date:tue, 08:12:31 GMT
Expect The specific server behavior of the request Expect:100-continue
From Email from the user who made the request From: [Email protected]
Host Specify the domain name and port number of the requested server
If-match Only valid if the request content matches the entity If-match: "737060cd8c284d8af7ad3082f209582d"
If-modified-since If the requested part is modified after the specified time, the request succeeds, and the 304 code is returned without modification If-modified-since:sat, Oct 19:43:31 GMT
If-none-match If the content does not change the return 304 code, the parameter is the server's previously sent ETag, and the server responded to the ETag comparison to determine whether the change If-none-match: "737060cd8c284d8af7ad3082f209582d"
If-range If the entity does not change, the server sends the missing portion of the client, otherwise the entire entity is sent. The parameters are also ETag If-range: "737060cd8c284d8af7ad3082f209582d"
If-unmodified-since Request succeeds only if the entity has not been modified since the specified time If-unmodified-since:sat, Oct 19:43:31 GMT
Max-forwards Limit the time that information is transmitted through agents and gateways Max-forwards:10
Pragma Used to include implementation-specific instructions Pragma:no-cache
Proxy-authorization Connect to an authorization certificate for the agent Proxy-authorization:basic qwxhzgrpbjpvcgvuihnlc2ftzq==
Range Request only part of an entity, specify a range range:bytes=500-999
Referer The address of the previous page, which is immediately followed by the current request page, Referer:
TE The client is willing to accept the transfer encoding and notifies the server to accept the trailing header information te:trailers,deflate;q=0.5
Upgrade Specify some kind of transport protocol to the server for the server to convert (if supported) upgrade:http/2.0, shttp/1.3, irc/6.9, rta/x11
User-agent The content of the user-agent contains the user information that made the request user-agent:mozilla/5.0 (Linux; X11)
Via Notifies the intermediary gateway or proxy server address, communication protocol via:1.0 Fred, 1.1 (apache/1.1)
Warning About warning messages for message entities warn:199 Miscellaneous Warning
Responses part
Header explain Example
Accept-ranges Indicates whether the server supports the specified range request and what kind of staging request Accept-ranges:bytes
Age Estimated time (in seconds, non-negative) from the original server to the proxy cache Age:12
Allow A valid request behavior for a network resource is not allowed to return 405 Allow:get, HEAD
Cache-control Tell if all caching mechanisms can be cached and which type Cache-control:no-cache
Content-encoding The type of return content compression encoding supported by the Web server. Content-encoding:gzip
Content-language The language of the response body Content-language:en,zh
Content-length The length of the response body content-length:348
Content-location Alternate alternative address to request resource substitution Content-location:/index.htm
Content-md5 Returns the MD5 checksum value of a resource content-md5:q2hly2sgsw50zwdyaxr5iq==
Content-range The byte position of this section in the entire return body Content-range:bytes 21010-47021/47022
Content-type Returns the MIME type of the content content-type:text/html; Charset=utf-8
Date Time the original server message was issued Date:tue, 08:12:31 GMT
ETag The current value of the entity label of the request variable ETag: "737060cd8c284d8af7ad3082f209582d"
Expires Date and time when the response expires Expires:thu, 16:00:00 GMT
Last-modified Requested last modified time for resource Last-modified:tue, 12:45:26 GMT
Location Used to redirect the receiver to the location of the non-request URL to complete the request or identify the new resource Location:
Pragma Includes implementing a specific instruction that can be applied to any receiver on the response chain Pragma:no-cache
Proxy-authenticate It indicates the authentication scheme and the parameters on the URL that can be applied to the proxy Proxy-authenticate:basic
Refresh Applied to redirect or a new resource was created, redirected after 5 seconds (proposed by Netscape, supported by most browsers)

Refresh:5; Url=

Retry-after Notifies the client to try again after a specified time if the entity is temporarily undesirable retry-after:120
Server Web Server Software Name server:apache/1.3.27 (Unix) (Red-hat/linux)
Set-cookie Set HTTP Cookies Set-cookie:userid=johndoe; max-age=3600; Version=1
Trailer Indicates that the header domain is present at the end of the chunked transfer code Trailer:max-forwards
Transfer-encoding File transfer encoding Transfer-encoding:chunked
Vary Tells the downstream agent whether to use the cache response or request from the original server Vary: *
Via Tells the proxy client where the response was sent by via:1.0 Fred, 1.1 (apache/1.1)
Warning Warning about possible issues with the entity warning:199 Miscellaneous Warning
Www-authenticate Indicates the authorization scheme that the client request entity should use Www-authenticate:basic

HTTP request headers and Response headers explained in detail

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