7.3.4.2 General Headers

General HTTP headers may be present in any HTTP message.

HTTP Header: KVList cache-control

A key-value list of cache-control directives. See RFC 2616, for more details.

If present, parameters to max-age, max-stale, min-fresh, and s-maxage are all parsed as non-negative integers.

If present, parameters to private and no-cache are parsed as lists of header names, as symbols.

(parse-header 'cache-control "no-cache,no-store"
⇒ (no-cache no-store)
(parse-header 'cache-control "no-cache=\"Authorization,Date\",no-store"
⇒ ((no-cache . (authorization date)) no-store)
(parse-header 'cache-control "no-cache=\"Authorization,Date\",max-age=10"
⇒ ((no-cache . (authorization date)) (max-age . 10))

HTTP Header: List connection

A list of header names that apply only to this HTTP connection, as symbols. Additionally, the symbol ‘close’ may be present, to indicate that the server should close the connection after responding to the request.

(parse-header 'connection "close")
⇒ (close)

HTTP Header: Date date

The date that a given HTTP message was originated.

(parse-header 'date "Tue, 15 Nov 1994 08:12:31 GMT")
⇒ #<date ...>

HTTP Header: KVList pragma

A key-value list of implementation-specific directives.

(parse-header 'pragma "no-cache, broccoli=tasty")
⇒ (no-cache (broccoli . "tasty"))

HTTP Header: List trailer

A list of header names which will appear after the message body, instead of with the message headers.

(parse-header 'trailer "ETag")
⇒ (etag)

HTTP Header: List transfer-encoding

A list of transfer codings, expressed as key-value lists. The only transfer coding defined by the specification is chunked.

(parse-header 'transfer-encoding "chunked")
⇒ ((chunked))

HTTP Header: List upgrade

A list of strings, indicating additional protocols that a server could use in response to a request.

(parse-header 'upgrade "WebSocket")
⇒ ("WebSocket")

FIXME: parse out more fully?

HTTP Header: List via

A list of strings, indicating the protocol versions and hosts of intermediate servers and proxies. There may be multiple via headers in one message.

(parse-header 'via "1.0 venus, 1.1 mars")
⇒ ("1.0 venus" "1.1 mars")

HTTP Header: List warning

A list of warnings given by a server or intermediate proxy. Each warning is a itself a list of four elements: a code, as an exact integer between 0 and 1000, a host as a string, the warning text as a string, and either #f or a SRFI-19 date.

There may be multiple warning headers in one message.

(parse-header 'warning "123 foo \"core breach imminent\"")
⇒ ((123 "foo" "core-breach imminent" #f))

This document was generated on April 20, 2013 using texi2html 5.0.