Suppose we want to load balance the traffic to www. To tell this to the server, the following. Variants can be associated with none, one or more than one language.
Variant description can also have a quality factor the "qs" parameter. Note that Options All does not set MultiViews; you have to ask for it by name.
Note that to use this feature, you must have a handler set in the configuration that defines a file suffix as type-map; this is best done with a AddHandler type-map.
To get here means no variant was selected because none are acceptable to the browser. Dedicated Load Balancers There are more sophisticated solutions, as well. This is done in one of two ways: If multiple representations are available, the resource is referred to as negotiable and each of its representations is termed a variant.
After each test, if only one variant remains, select it as the best match and proceed to step 3. Encoding Browser indicates preference with the Accept-Encoding header field.
There are software packages which offer similar features on commodity hardware, as well. Some of the most popular browsers send Accept header information which would otherwise result in the selection of the wrong variant in many cases. For example, a browser could indicate that it would like to see information in French, if possible, else English will do.
The trick is that the external web server retrieves the requested data on-the-fly from the internal one.
Different languages, file types, content encodings, and character sets can be automatically delivered to different browsers based on browser-supplied preferences sent in header requests. Select the first variant of those remaining. The MultiViews option expresses no server-side preference and effectively fakes a type map file from searching the directory for files with MIME type extensions.
But the overall result is okay because the requests are collectively spread over the various web servers. On a packet-filtering firewall, for instance, we could configure a firewall ruleset like the following: The HTTP response header Vary is set to indicate the dimensions of negotiation browsers and caches can use this information when caching the resource.
To get here means no variant was selected because non are acceptable to the browser. For example, a browser could indicate that it would like to see information in French, if possible, else English will do.
Now, when a request for info. This will be either the first listed in the type-map file, or when variants are read from the directory, the one whose file name comes first when sorted using ASCII code order.
Variants can be associated with none, one or more languages. The answer is yes, it is overloaded, but with plain proxy throughput requests, only! However, if no other language match is possible and the server is about to return a "No Acceptable Variants" error or fallback to the LanguagePrioritythe server will ignore the subset specification and match en-GB against en documents.
Engelschall, All Rights Reserved. Media Types and Wildcards The Accept: See Variants with no Language below for details. Charset Browser indicates preference with Accept-Charset: We explain how to use negotiation correctly, and why some browsers make this difficult.
If you want to avoid users seeing this error page, you should organize your documents such that a document in a default language or with a default encoding etc. One way of selecting the most appropriate choice is to give the user an index page, and let them select.
Using a type map i. An example map file is: If there are no such variants, select all variants instead.
By setting the multiviews option in your server configuration or. If the browser does not list either en or fr as acceptable, foo. Select the variants with the best language match, using either the order of languages in the Accept-Language header if presentor else the order of languages in the LanguagePriority directive if present.
Language Negotiation Exceptions New in Apache 2.Not the answer you're looking for?
Browse other questions tagged apache mod-rewrite github-pages content-negotiation linked-data or ask your own question. Content Negotiation Apache's support for content negotiation has been updated to meet the HTTP/ specification.
It can choose the best representation of a resource based on the browser-supplied preferences for media type, languages, character set and encoding. I would like to write a rules that says, whenever that resource is requested, if the content type is X return the file_x, if it is Y return file_Y Can anyone help here?
Many thanks, -D. Apache supports content negotiation as described in the HTTP/ specification. It can choose the best representation of a resource based on the browser-supplied preferences for media type, languages, character set and encoding.
It also implements a couple of features to give more intelligent. URL Rewriting Guide - Advanced topics. It describes how one can use Apache's mod_rewrite to solve typical URL-based problems with which webmasters are commonly confronted.
We give detailed descriptions on how to solve each problem by configuring URL rewriting rulesets. We cannot use content negotiation because the browsers do not. What Is Content Negotiation? Content negotiation is a little-used feature of Apache and IIS that transparently delivers the best variant of the same resource to browsers.
Browsers tell servers their preferences, and servers tune their responses to select the best resource.Download