Apache module mod_autoindex

### Apache HTTP Server Version 1.3

# Module mod_autoindex

This module is contained in the `mod_autoindex.c` file, and is compiled in by default. It provides for automatic directory indexing.

## Summary

The index of a directory can come from one of two sources:

- A file written by the user, typically called `index.html`. The DirectoryIndex directive sets the name of this file. This is controlled by `mod_dir`.
- Otherwise, a listing generated by the server. The other directives control the format of this listing. The AddIcon, AddIconByEncoding and AddIconByType are used to set a list of icons to display for various file types; for each file listed, the first icon listed that matches the file is displayed. These are controlled by `mod_autoindex`.

The two functions are separated so that you can completely remove (or replace) automatic index generation should you want to.

If `FancyIndexing` is enabled, or the `FancyIndexing` keyword is present on the `IndexOptions` directive, the column headers are links that control the order of the display. If you select a header link, the listing will be regenerated, sorted by the values in that column. Selecting the same header repeatedly toggles between ascending and descending order.

Note that when the display is sorted by "Size", it's the actual size of the files that's used, not the displayed value - so a 1010-byte file will always be displayed before a 1011-byte file (if in ascending order) even though they both are shown as "1K".

## Directives

- AddAlt
- AddAltByEncoding
- AddAltByType
- AddDescription
- AddIcon
- AddIconByEncoding
- AddIconByType
- DefaultIcon
- FancyIndexing
- HeaderName
- IndexIgnore
- IndexOptions
- IndexOrderDefault
- ReadmeName

## AddAlt

Syntax: AddAlt string file file...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the alternate text to display for a file, instead of an icon, for FancyIndexing. File is a file extension, partial filename, wild-card expression or full filename for files to describe. String is enclosed in double quotes (`"`). This alternate text is displayed if the client is image-incapable or has image loading disabled.

## AddAltByEncoding

Syntax: AddAltByEncoding string MIME-encoding MIME-encoding...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the alternate text to display for a file, instead of an icon, for FancyIndexing. MIME-encoding is a valid content-encoding, such as `x-compress`. String is enclosed in double quotes (`"`). This alternate text is displayed if the client is image-incapable or has image loading disabled.

## AddAltByType

Syntax: AddAltByType string MIME-type MIME-type ...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the alternate text to display for a file, instead of an icon, for FancyIndexing. MIME-type is a valid content-type, such as `text/html`. String is enclosed in double quotes (`"`). This alternate text is displayed if the client is image-incapable or has image loading disabled.

## AddDescription

Syntax: AddDescription string file file...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the description to display for a file, for FancyIndexing. File is a file extension, partial filename, wild-card expression or full filename for files to describe. String is enclosed in double quotes (`"`). Example:

> `AddDescription "The planet Mars" /web/pics/mars.gif`

The description field is 23 bytes wide. 7 more bytes may be added if the directory is covered by an `IndexOptions SuppressSize`, and 19 bytes may be added if `IndexOptions SuppressLastModified` is in effect. The widest this column can be is therefore 49 bytes.

## AddIcon

Syntax: AddIcon icon name name ...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the icon to display next to a file ending in name for FancyIndexing. Icon is either a (%-escaped) relative URL to the icon, or of the format (alttext,url) where alttext is the text tag given for an icon for non-graphical browsers.

Name is either ^^DIRECTORY^^ for directories, ^^BLANKICON^^ for blank lines (to format the list correctly), a file extension, a wildcard expression, a partial filename or a complete filename. Examples:

> `AddIcon (IMG,/icons/image.xbm) .gif .jpg .xbm
> AddIcon /icons/dir.xbm ^^DIRECTORY^^
> AddIcon /icons/backup.xbm *~`

AddIconByType should be used in preference to AddIcon, when possible.

## AddIconByEncoding

Syntax: AddIconByEncoding icon MIME-encoding MIME-encoding ...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the icon to display next to files with MIME-encoding for FancyIndexing. Icon is either a (%-escaped) relative URL to the icon, or of the format (alttext,url) where alttext is the text tag given for an icon for non-graphical browsers.

Mime-encoding is a wildcard expression matching required the content-encoding. Examples:

> `AddIconByEncoding /icons/compress.xbm x-compress`

## AddIconByType

Syntax: AddIconByType icon MIME-type MIME-type ...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

This sets the icon to display next to files of type MIME-type for FancyIndexing. Icon is either a (%-escaped) relative URL to the icon, or of the format (alttext,url) where alttext is the text tag given for an icon for non-graphical browsers.

Mime-type is a wildcard expression matching required the mime types. Examples:

> `AddIconByType (IMG,/icons/image.xbm) image/*`

## DefaultIcon

Syntax: DefaultIcon url
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

The DefaultIcon directive sets the icon to display for files when no specific icon is known, for FancyIndexing. Url is a (%-escaped) relative URL to the icon. Examples:

> `DefaultIcon /icon/unknown.xbm`

## FancyIndexing

Syntax: FancyIndexing boolean
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

The FancyIndexing directive sets the FancyIndexing option for a directory. Boolean can be `on` or `off`. The IndexOptions directive should be used in preference.

> Note that in versions of Apache prior to 1.3.2, the `FancyIndexing` and `IndexOptions` directives will override each other. You should use `IndexOptions FancyIndexing` in preference to the standalone `FancyIndexing` directive. As of Apache 1.3.2, a standalone `FancyIndexing` directive is combined with any `IndexOptions` directive already specified for the current scope.

## HeaderName

Syntax: HeaderName filename
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

The HeaderName directive sets the name of the file that will be inserted at the top of the index listing. Filename is the name of the file to include, and is taken to be relative to the directory being indexed. The server first attempts to include filename`.html` as an HTML document, otherwise it will include filename as plain text. Example:

> `HeaderName HEADER`

when indexing the directory `/web`, the server will first look for the HTML file `/web/HEADER.html` and include it if found, otherwise it will include the plain text file `/web/HEADER`, if it exists.

See also ReadmeName.

## IndexIgnore

Syntax: IndexIgnore file file ...
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

The IndexIgnore directive adds to the list of files to hide when listing a directory. File is a file extension, partial filename, wildcard expression or full filename for files to ignore. Multiple IndexIgnore directives add to the list, rather than the replacing the list of ignored files. By default, the list contains ``.`'. Example:

> `IndexIgnore README .htaccess *~`

## IndexOptions

Syntax: IndexOptions option option ... (Apache 1.3.2 and earlier)
Syntax: IndexOptions [+|-]option [+|-]option ... (Apache 1.3.3 and later)
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex
Compatibility: '+/-' syntax and merging of multiple `IndexOptions` directives is only available with Apache 1.3.3 and later

The IndexOptions directive specifies the behavior of the directory indexing. Option can be one of

FancyIndexing
  This turns on fancy indexing of directories.

  > Note that in versions of Apache prior to 1.3.2, the `FancyIndexing` and `IndexOptions` directives will override each other. You should use `IndexOptions FancyIndexing` in preference to the standalone `FancyIndexing` directive. As of Apache 1.3.2, a standalone `FancyIndexing` directive is combined with any `IndexOptions` directive already specified for the current scope.

IconHeight[=pixels] (Apache 1.3 and later)
  Presence of this option, when used with IconWidth, will cause the server to include `HEIGHT` and `WIDTH` attributes in the `IMG` tag for the file icon. This allows browser to precalculate the page layout without having to wait until all the images have been loaded. If no value is given for the option, it defaults to the standard height of the icons supplied with the Apache software.
IconsAreLinks
  This makes the icons part of the anchor for the filename, for fancy indexing.
IconWidth[=pixels] (Apache 1.3 and later)
  Presence of this option, when used with IconHeight, will cause the server to include `HEIGHT` and `WIDTH` attributes in the `IMG` tag for the file icon. This allows browser to precalculate the page layout without having to wait until all the images have been loaded. If no value is given for the option, it defaults to the standard width of the icons supplied with the Apache software.
NameWidth=[n | *] (Apache 1.3.2 and later)
  The NameWidth keyword allows you to specify the width of the filename column in bytes. If the keyword value is '`*`', then the column is automatically sized to the length of the longest filename in the display.
ScanHTMLTitles
  This enables the extraction of the title from HTML documents for fancy indexing. If the file does not have a description given by AddDescription then httpd will read the document for the value of the TITLE tag. This is CPU and disk intensive.
SuppressColumnSorting
  If specified, Apache will not make the column headings in a FancyIndexed directory listing into links for sorting. The default behaviour is for them to be links; selecting the column heading will sort the directory listing by the values in that column. Only available in Apache 1.3 and later.
SuppressDescription
  This will suppress the file description in fancy indexing listings.
SuppressHTMLPreamble (Apache 1.3 and later)
  If the directory actually contains a file specified by the HeaderName directive, the module usually includes the contents of the file after a standard HTML preamble (<HTML>, <HEAD>, et cetera). The SuppressHTMLPreamble option disables this behaviour, causing the module to start the display with the header file contents. The header file must contain appropriate HTML instructions in this case. If there is no header file, the preamble is generated as usual.
SuppressLastModified
  This will suppress the display of the last modification date, in fancy indexing listings.
SuppressSize
  This will suppress the file size in fancy indexing listings.

There are some noticeable differences in the behaviour of this directive in recent (post-1.3.0) versions of Apache.

Apache 1.3.2 and earlier:

  The default is that no options are enabled. If multiple IndexOptions could apply to a directory, then the most specific one is taken complete; the options are not merged. For example:

  > `<Directory /web/docs>
  > IndexOptions FancyIndexing
  > </Directory>
  > <Directory /web/docs/spec>
  > IndexOptions ScanHTMLTitles
  > </Directory>`

  then only `ScanHTMLTitles` will be set for the /web/docs/spec directory.
Apache 1.3.3 and later:

  Apache 1.3.3 introduced some significant changes in the handling of `IndexOptions` directives. In particular,

  - Multiple `IndexOptions` directives for a single directory are now merged together. The result of the example above will now be the equivalent of `IndexOptions FancyIndexing ScanHTMLTitles`.
  - The addition of the incremental syntax (i.e., prefixing keywords with '+' or '-').

  Whenever a '+' or '-' prefixed keyword is encountered, it is applied to the current `IndexOptions` settings (which may have been inherited from an upper-level directory). However, whenever an unprefixed keyword is processed, it clears all inherited options and any incremental settings encountered so far. Consider the following example:

  > `IndexOptions +ScanHTMLTitles -IconsAreLinks FancyIndexing
  > IndexOptions +SuppressSize
  > `

  The net effect is equivalent to `IndexOptions FancyIndexing +SuppressSize`, because the unprefixed `FancyIndexing` discarded the incremental keywords before it, but allowed them to start accumulating again afterward.

  To unconditionally set the `IndexOptions` for a particular directory, clearing the inherited settings, specify keywords without either '+' or '-' prefixes.

## IndexOrderDefault

Syntax: IndexOrderDefault Ascending|Descending Name|Date|Size|Description
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex
Compatibility: IndexOrderDefault is only available in Apache 1.3.4 and later.

The `IndexOrderDefault` directive is used in combination with the `FancyIndexing` index option. By default, fancyindexed directory listings are displayed in ascending order by filename; the `IndexOrderDefault` allows you to change this initial display order.

`IndexOrderDefault` takes two arguments. The first must be either `Ascending` or `Descending`, indicating the direction of the sort. The second argument must be one of the keywords `Name`, `Date`, `Size`, or `Description`, and identifies the primary key. The secondary key is always the ascending filename.

You can force a directory listing to only be displayed in a particular order by combining this directive with the `SuppressColumnSorting` index option; this will prevent the client from requesting the directory listing in a different order.

## ReadmeName

Syntax: ReadmeName filename
Context: server config, virtual host, directory, .htaccess
Override: Indexes
Status: Base
Module: mod_autoindex

The ReadmeName directive sets the name of the file that will be appended to the end of the index listing. Filename is the name of the file to include, and is taken to be relative to the directory being indexed. The server first attempts to include filename`.html` as an HTML document, otherwise it will include filename as plain text. Example:

> `ReadmeName README`

when indexing the directory `/web`, the server will first look for the HTML file `/web/README.html` and include it if found, otherwise it will include the plain text file `/web/README`, if it exists.

See also HeaderName.

### Apache HTTP Server Version 1.3