This module provides for content negotiation.
Status: Base
Source File:
mod_negotiation.c
Module Identifier:
negotiation_module
type-map) which explicitly lists the files
containing the variants.x-compress
for compress'd files, and x-gzip for gzip'd
files. The x- prefix is ignored for encoding
comparisons.en,
meaning English.name=value. Common parameters include:
text/html this defaults to 2, otherwise
0.
Content-Type: image/jpeg; qs=0.8
/some/dir/foo and
/some/dir/foo does not exist, then the
server reads the directory looking for all files named
foo.*, and effectively fakes up a type map which
names all those files, assigning them the same media types and
content-encodings it would have if the client had asked for one
of them by name. It then chooses the best match to the client's
requirements, and returns that document.
CacheNegotiatedDocs offIf set, this directive allows content-negotiated documents to be cached by proxy servers. This could mean that clients behind those proxys could retrieve versions of the documents that are not the best match for their abilities, but it will make caching more efficient.
This directive only applies to requests which come from HTTP/1.0 browsers. HTTP/1.1 provides much better control over the caching of negotiated documents, and this directive has no effect in responses to HTTP/1.1 requests.
Prior to version 2.0, CacheNegotiatedDocs did not take an argument; it was turned on by the presence of the directive by itself.
Syntax: ForceLanguagePriority
None|Prefer|Fallback [Prefer|Fallback]
Default:
ForceLanguagePriority None
Context: server config, virtual
host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_negotiation
Compatibility:
Available in version 2.0.30 and later.
The ForceLanguagePriority directive uses the given
LanguagePriority to satisfy
negotation where the server could otherwise not return a single
matching document.
ForceLanguagePriority Prefer uses
LanguagePriority to serve a one valid result, rather
than returning an HTTP result 300 (MULTIPLE CHOICES) when there
are several equally valid choices. If the directives below were
given, and the user's Accept-Language header assigned en and de
each as quality .500 (equally acceptable) then then first matching
variant, en, will be served.
LanguagePriority en fr de
ForceLanguagePriority Prefer
ForceLanguagePriority Fallback uses
LanguagePriority to serve a valid result, rather than
returning an HTTP result 406 (NOT ACCEPTABLE). If the directives
below were given, and the user's Accept-Language only permitted an
es langauge response, but such a variant isn't found, then the
first variant from the LanguagePriority list below will be
served.
LanguagePriority en fr de
ForceLanguagePriority Fallback
Both options, Prefer and Fallback, may be specified, so either the first matching variant from LanguagePriority will be served if more that one variant is acceptable, or first available document will be served if none of the variants matched the client's acceptable list of languages.
The LanguagePriority sets the precedence of language variants for the case where the client does not express a preference, when handling a MultiViews request. The list of MIME-lang are in order of decreasing preference. Example:
LanguagePriority en fr de
For a request for foo.html, where
foo.html.fr and foo.html.de both
existed, but the browser did not express a language preference,
then foo.html.fr would be returned.
Note that this directive only has an effect if a 'best'
language cannot be determined by any other means or the ForceLanguagePriority directive
is not None. Correctly implemented HTTP/1.1 requests
will mean this directive has no effect.
See also: DefaultLanguage, AddLanguage and ForceLanguagePriority.