Return-Path:
This module controls the setting of the These HTTP headers are an instruction to the client about the
+ document's validity and persistence. If cached, the document may
+ be fetched from the cache rather than from the source until this
+ time has passed. After that, the cache copy is considered
+ "expired" and invalid, and a new copy must be obtained from the
+ source. To modify The This directive enables or disables the generation of the
-
+Description: Generation of Expires
HTTP headers according to
-user-specified criteriaDescription: Generation of Expires
and
+Cache-Control
HTTP headers according to user-specified
+criteriaStatus: Extension Module�Identifier: expires_module Source�File: mod_expires.c Summary
Expires
- HTTP header in server responses. The expiration date can set to
- be relative to either the time the source file was last
- modified, or to the time of the client access.max-age
directive of the
+ Cache-Control
HTTP header in server responses. The
+ expiration date can set to be relative to either the time the
+ source file was last modified, or to the time of the client
+ access.
+
+ Cache-Control
directives other than
+ max-age
(see RFC
+ 2616 section 14.9), you can use the Header
directive.Expires
HTTP header is an instruction to
- the client about the document's validity and persistence. If
- cached, the document may be fetched from the cache rather than
- from the source until this time has passed. After that, the
- cache copy is considered "expired" and invalid, and a new copy
- must be obtained from the source.Directives
@@ -129,23 +137,25 @@
Module: mod_expires Expires
header for the document realm in question.
- (That is, if found in an .htaccess
file, for
- instance, it applies only to documents generated from that
- directory.) If set to Off
, no Expires
header
- will be generated for any document in the realm (unless overridden at
- a lower level, such as an .htaccess
file overriding a
- server config file). If set to On
, the header will be
- added to served documents according to the criteria defined by the
- ExpiresByType
and
- ExpiresDefault
directives
- (q.v.).Expires
and Cache-Control
headers for
+ the document realm in question. (That is, if found in an
+ .htaccess
file, for instance, it applies only to
+ documents generated from that directory.) If set to
+ Off
, the headers will not be generated for any
+ document in the realm (unless overridden at a lower level, such as
+ an .htaccess
file overriding a server config
+ file). If set to On
, the headers will be added to
+ served documents according to the criteria defined by the
+ ExpiresByType
and
+ ExpiresDefault
+ directives (q.v.).
Note that this directive does not guarantee that an
- Expires
header will be generated. If the criteria
- aren't met, no header will be sent, and the effect will be as
- though this directive wasn't even specified.
Expires
or Cache-Control
header will be
+ generated. If the criteria aren't met, no header will be sent, and
+ the effect will be as though this directive wasn't even
+ specified.
+
This directive defines the value of the Expires
- header generated for documents of the specified type (e.g.,
- text/html
). The second argument sets the number of
- seconds that will be added to a base time to construct the expiration
- date.
max-age
directive of the
+ Cache-Control
header generated for documents of the
+ specified type (e.g., text/html
). The second
+ argument sets the number of seconds that will be added to a base
+ time to construct the expiration date. The Cache-Control:
+ max-age
is calculated by subtracting the request time from
+ the expiration date and expressing the result in seconds.
The base time is either the last modification time of the file, or the time of the client's access to the document. Which @@ -229,4 +242,4 @@