Module mod_mime

This module provides for determining the types of files from the filename and for association of handlers with files.

Status: Base
Source File: mod_mime.c
Module Identifier: mime_module

Summary

This module is used to determine various bits of "meta information" about documents. This information relates to the content of the document and is returned to the browser or used in content-negotiation within the server. In addition, a "handler" can be set for a document, which determines how the document will be processed within the server.

The directives AddCharset, AddEncoding, AddHandler, AddLanguage and AddType are all used to map file extensions onto the meta-information for that file. Respectively they set the character set, content-encoding, handler, content-language, and MIME-type (content-type) of documents. The directive TypesConfig is used to specify a file which also maps extensions onto MIME types. The directives ForceType and SetHandler are used to associated all the files in a given location (e.g., a particular directory) onto a particular MIME type or handler.

Note that changing the type or encoding of a file does not change the value of the Last-Modified header. Thus, previously cached copies may still be used by a client or proxy, with the previous headers.

Directives

See also: MimeMagicFile.

Files with Multiple Extensions

Files can have more than one extension, and the order of the extensions is normally irrelevant. For example, if the file welcome.html.fr maps onto content type text/html and language French then the file welcome.fr.html will map onto exactly the same information. The only exception to this is if an extension is given which Apache does not know how to handle. In this case it will "forget" about any information it obtained from extensions to the left of the unknown extension. So, for example, if the extensions fr and html are mapped to the appropriate language and type but extension xxx is not assigned to anything, then the file welcome.fr.xxx.html will be associated with content-type text/html but no language.

If more than one extension is given which maps onto the same type of meta-information, then the one to the right will be used. For example, if ".gif" maps to the MIME-type image/gif and ".html" maps to the MIME-type text/html, then the file welcome.gif.html will be associated with the MIME-type "text/html".

Care should be taken when a file with multiple extensions gets associated with both a MIME-type and a handler. This will usually result in the request being by the module associated with the handler. For example, if the .imap extension is mapped to the handler "imap-file" (from mod_imap) and the .html extension is mapped to the MIME-type "text/html", then the file world.imap.html will be associated with both the "imap-file" handler and "text/html" MIME-type. When it is processed, the "imap-file" handler will be used, and so it will be treated as a mod_imap imagemap file.


AddCharset directive

Syntax: AddCharset charset extension [extension] ...
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_mime
Compatibility: AddCharset is only available in Apache 1.3.10 and later

The AddCharset directive maps the given filename extensions to the specified content charset. charset is the MIME charset parameter of filenames containing extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension.

Example:

    AddLanguage ja .ja
    AddCharset EUC-JP .euc
    AddCharset ISO-2022-JP .jis
    AddCharset SHIFT_JIS .sjis

Then the document xxxx.ja.jis will be treated as being a Japanese document whose charset is ISO-2022-JP (as will the document xxxx.jis.ja). The AddCharset directive is useful for both to inform the client about the character encoding of the document so that the document can be interpreted and displayed appropriately, and for content negotiation, where the server returns one from several documents based on the client's charset preference.

The extension argument is case-insensitive, and can be specified with or without a leading dot.

See also: mod_negotiation


AddEncoding directive

Syntax: AddEncoding MIME-enc extension [extension] ...
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_mime

The AddEncoding directive maps the given filename extensions to the specified encoding type. MIME-enc is the MIME encoding to use for documents containing the extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension. Example:

AddEncoding x-gzip .gz
AddEncoding x-compress .Z
This will cause filenames containing the .gz extension to be marked as encoded using the x-gzip encoding, and filenames containing the .Z extension to be marked as encoded with x-compress.

Old clients expect x-gzip and x-compress, however the standard dictates that they're equivalent to gzip and compress respectively. Apache does content encoding comparisons by ignoring any leading x-. When responding with an encoding Apache will use whatever form (i.e., x-foo or foo) the client requested. If the client didn't specifically request a particular form Apache will use the form given by the AddEncoding directive. To make this long story short, you should always use x-gzip and x-compress for these two specific encodings. More recent encodings, such as deflate should be specified without the x-.

The extension argument is case-insensitive, and can be specified with or without a leading dot.

See also: Files with multiple extensions


AddHandler directive

Syntax: AddHandler handler-name extension [extension] ...
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_mime
Compatibility: AddHandler is only available in Apache 1.1 and later

AddHandler maps the filename extensions extension to the handler handler-name. This mapping is added to any already in force, overriding any mappings that already exist for the same extension. For example, to activate CGI scripts with the file extension ".cgi", you might use:

    AddHandler cgi-script .cgi

Once that has been put into your srm.conf or httpd.conf file, any file containing the ".cgi" extension will be treated as a CGI program.

The extension argument is case-insensitive, and can be specified with or without a leading dot.

See also: Files with multiple extensions


AddLanguage directive

Syntax: AddLanguage MIME-lang extension [extension] ...
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_mime

The AddLanguage directive maps the given filename extension to the specified content language. MIME-lang is the MIME language of filenames containing extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension.

Example:

AddEncoding x-compress .Z
AddLanguage en .en
AddLanguage fr .fr

Then the document xxxx.en.Z will be treated as being a compressed English document (as will the document xxxx.Z.en). Although the content language is reported to the client, the browser is unlikely to use this information. The AddLanguage directive is more useful for content negotiation, where the server returns one from several documents based on the client's language preference.

If multiple language assignments are made for the same extension, the last one encountered is the one that is used. That is, for the case of:

    AddLanguage en .en
    AddLanguage en-uk .en
    AddLanguage en-us .en

documents with the extension ".en" would be treated as being "en-us".

The extension argument is case-insensitive, and can be specified with or without a leading dot.

See also: Files with multiple extensions
See also: mod_negotiation


AddType directive

Syntax: AddType MIME-type extension [extension] ...
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_mime

The AddType directive maps the given filename extensions onto the specified content type. MIME-type is the MIME type to use for filenames containing extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension. This directive can be used to add mappings not listed in the MIME types file (see the TypesConfig directive). Example:

AddType image/gif .gif
It is recommended that new MIME types be added using the AddType directive rather than changing the TypesConfig file.

Note that, unlike the NCSA httpd, this directive cannot be used to set the type of particular files.

The extension argument is case-insensitive, and can be specified with or without a leading dot.

See also: Files with multiple extensions


DefaultLanguage directive

Syntax: DefaultLanguage MIME-lang
Context: server config, virtual host, directory, .htaccess
Override: FileInfo
Status: Base
Module: mod_mime
Compatibility: DefaultLanguage is only available in Apache 1.3.4 and later.

The DefaultLanguage directive tells Apache that all files in the directive's scope (e.g., all files covered by the current <Directory> container) that don't have an explicit language extension (such as .fr or .de as configured by AddLanguage) should be considered to be in the specified MIME-lang language. This allows entire directories to be marked as containing Dutch content, for instance, without having to rename each file. Note that unlike using extensions to specify languages, DefaultLanguage can only specify a single language.

If no DefaultLanguage directive is in force, and a file does not have any language extensions as configured by AddLanguage, then that file will be considered to have no language attribute.

See also: mod_negotiation
See also: Files with multiple extensions


ForceType directive

Syntax: ForceType media-type
Context: directory, .htaccess
Status: Base
Module: mod_mime
Compatibility: ForceType is only available in Apache 1.1 and later.

When placed into an .htaccess file or a <Directory> or <Location> section, this directive forces all matching files to be served as the content type given by media type. For example, if you had a directory full of GIF files, but did not want to label them all with ".gif", you might want to use:

    ForceType image/gif

Note that this will override any filename extensions that might determine the media type.


RemoveEncoding directive

Syntax: RemoveEncoding extension [extension] ...
Context: directory, .htaccess
Status: Base
Module: mod_mime
Compatibility: RemoveEncoding is only available in Apache 1.3.13 and later.

The RemoveEncoding directive removes any encoding associations for files with the given extensions. This allows .htaccess files in subdirectories to undo any associations inherited from parent directories or the server config files. An example of its use might be:

/foo/.htaccess:
AddEncoding x-gzip .gz
AddType text/plain .asc
<Files *.gz.asc>
    RemoveEncoding .gz
</Files>

This will cause foo.gz to mark as being encoded with the gzip method, but foo.gz.asc as an unencoded plaintext file.

Note:RemoveEncoding directives are processed after any AddEncoding directives, so it is possible they may undo the effects of the latter if both occur within the same directory configuration.

The extension argument is case-insensitive, and can be specified with or without a leading dot.


RemoveHandler directive

Syntax: RemoveHandler extension [extension] ...
Context: directory, .htaccess
Status: Base
Module: mod_mime
Compatibility: RemoveHandler is only available in Apache 1.3.4 and later.

The RemoveHandler directive removes any handler associations for files with the given extensions. This allows .htaccess files in subdirectories to undo any associations inherited from parent directories or the server config files. An example of its use might be:

/foo/.htaccess:
AddHandler server-parsed .html
/foo/bar/.htaccess:
RemoveHandler .html

This has the effect of returning .html files in the /foo/bar directory to being treated as normal files, rather than as candidates for parsing (see the mod_include module).

The extension argument is case-insensitive, and can be specified with or without a leading dot.


RemoveType directive

Syntax: RemoveType extension [extension] ...
Context: directory, .htaccess
Status: Base
Module: mod_mime
Compatibility: RemoveType is only available in Apache 1.3.13 and later.

The RemoveType directive removes any MIME type associations for files with the given extensions. This allows .htaccess files in subdirectories to undo any associations inherited from parent directories or the server config files. An example of its use might be:

/foo/.htaccess:
RemoveType .cgi

This will remove any special handling of .cgi files in the /foo/ directory and any beneath it, causing the files to be treated as being of the default type.

Note:RemoveType directives are processed after any AddType directives, so it is possible they may undo the effects of the latter if both occur within the same directory configuration.

The extension argument is case-insensitive, and can be specified with or without a leading dot.


SetHandler directive

Syntax: SetHandler handler-name
Context: directory, .htaccess
Status: Base
Module: mod_mime
Compatibility: SetHandler is only available in Apache 1.1 and later.

When placed into an .htaccess file or a <Directory> or <Location> section, this directive forces all matching files to be parsed through the handler given by handler-name. For example, if you had a directory you wanted to be parsed entirely as imagemap rule files, regardless of extension, you might put the following into an .htaccess file in that directory:

    SetHandler imap-file

Another example: if you wanted to have the server display a status report whenever a URL of http://servername/status was called, you might put the following into access.conf:

    <Location /status>
    SetHandler server-status
    </Location>

TypesConfig directive

Syntax: TypesConfig filename
Default: TypesConfig conf/mime.types
Context: server config
Status: Base
Module: mod_mime

The TypesConfig directive sets the location of the MIME types configuration file. Filename is relative to the ServerRoot. This file sets the default list of mappings from filename extensions to content types; changing this file is not recommended. Use the AddType directive instead. The file contains lines in the format of the arguments to an AddType command:

MIME-type extension extension ...
The extensions are lower-cased. Blank lines, and lines beginning with a hash character (`#') are ignored.