public Interface HttpResponseHeader

What partial content range types this server supports.

Example: Accept-Ranges: bytes

Specifying which web sites can participate in cross-origin resource sharing.

Example: Access-Control-Allow-Origin: *

The age the object has been in a proxy cache in seconds.

Example: Age: 12

Valid actions for a specified resource. To be used for a 405 Method not allowed.

Example: Allow: GET, HEAD

Tells all caching mechanisms from server to client whether they may cache this object. It is measured in seconds.

Example: Cache-Control: max-age=3600

Options that are desired for the connection.

Example: Connection: close

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.

Example: Content-Disposition: attachment; filename="fname.ext"

The type of encoding used on the data. See HTTP compression.

Example: Content-Encoding: gzip

The language the content is in.

Example: Content-Language: da

The length of the response body in octets (8-bit bytes).

Example: Content-Length: 348

An alternate location for the returned data.

Example: Content-Location: /index.htm

A Base64-encoded binary MD5 sum of the content of the response.

Example: Content-MD5: Q2hlY2sgSW50ZWdyaXR5IQ==

Where in a full body message this partial message belongs.

Example: Content-Range: bytes 21010-47021/47022

The MIME type of this content.

Example: Content-Type: text/html; charset=utf-8

The date and time that the message was sent (in "HTTP-date" format as defined by RFC 7231).

Example: Date: Tue, 15 Nov 1994 08:12:31 GMT

An identifier for a specific version of a resource, often a message digest.

Example: ETag: "737060cd8c284d8af7ad3082f209582d"

Gives the date/time after which the response is considered stale.

Example: Expires: Thu, 01 Dec 1994 16:00:00 GMT

The last modified date for the requested object (in "HTTP-date" format as defined by RFC 7231).

Example: Last-Modified: Tue, 15 Nov 1994 12:45:26 GMT

Used to express a typed relationship with another resource, where the relation type is defined by RFC 5988.

Example: Link: ; rel="alternate"

Used in redirection, or when a new resource has been created.

Example: Location: http://www.w3.org/pub/WWW/People.html

This field is supposed to set P3P policy, in the form of P3P:CP="your_compact_policy". However, P3P did not take off, 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.

Example: 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."

Implementation-specific fields that may have various effects anywhere along the request-response chain.

Example: Pragma: no-cache

Request authentication to access the proxy.

Example: Proxy-Authenticate: Basic

Used in redirection, or when a new resource has been created. This refresh redirects after 5 seconds.

Example: Refresh: 5; url=http://www.w3.org/pub/WWW/People.html

If 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.

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

A name for the server.

Example: Server: Apache/2.4.1 (Unix)

An HTTP cookie.

Example: Set-Cookie: UserID=JohnDoe; Max-Age=3600; Version=1

CGI header field specifying the status of the HTTP response. Normal HTTP responses use a separate "Status-Line" instead, defined by RFC 7230.

Example: Status: 200 OK

A HSTS Policy informing the HTTP client how long to cache the HTTPS only policy and whether this applies to subdomains.

Example: Strict-Transport-Security: max-age=16070400; includeSubDomains

The 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.

Example: Trailer: Max-Forwards

The form of encoding used to safely transfer the entity to the user. Currently defined methods are: chunked, compress, deflate, gzip, identity.

Example: Transfer-Encoding: chunked

Ask the client to upgrade to another protocol.

Example: Upgrade: HTTP/2.0, SHTTP/1.3, IRC/6.9, RTA/x11

Tells 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: Vary: *

Informs the client of proxies through which the response was sent.

Example: Via: 1.0 fred, 1.1 example.com (Apache/1.1)

A general warning about possible problems with the entity body.

Example: Warning: 199 Miscellaneous warning

Indicates the authentication scheme that should be used to access the requested entity.

Example: WWW-Authenticate: Basic