Apache Module mod_imagemap

Summary

This module processes.map files, thereby replacing the functionality of theimagemap CGI program. Any directory or document type configured to use the handlerimap-file (using eitherAddHandler orSetHandler) will be processed by this module.

The following directive will activate files ending with.map as imagemap files:

AddHandler imap-file map

Note that the following is still supported:

AddType application/x-httpd-imap map

However, we are trying to phase out "magic MIME types" so we are deprecating this method.

Topics

• New Features
• Imagemap File
• Example Mapfile
• Referencing your mapfile

Directives

• ImapBase
• ImapDefault
• ImapMenu

Bugfix checklist

• httpd changelog
• Known issues
• Report a bug

See also

• Comments

New Features

The imagemap module adds some new features that were not possible with previously distributed imagemap programs.

• URL references relative to the Referer: information.
• Default<base> assignment through a new map directivebase.
• No need forimagemap.conf file.
• Point references.
• Configurable generation of imagemap menus.

Imagemap File

The lines in the imagemap files can have one of several formats:

The directive is one ofbase,default,poly,circle,rect, orpoint. The value is an absolute or relative URL, or one of the special values listed below. The coordinates arex,y pairs separated by whitespace. The quoted text is used as the text of the link if a imagemap menu is generated. Lines beginning with '#' are comments.

Imagemap File Directives

There are six directives allowed in the imagemap file. The directives can come in any order, but are processed in the order they are found in the imagemap file.

base Directive

Has the effect of<base href="value">. The non-absolute URLs of the map-file are taken relative to this value. Thebase directive overridesImapBase as set in a.htaccess file or in the server configuration files. In the absence of anImapBase configuration directive,base defaults tohttp://server_name/.

base_uri is synonymous withbase. Note that a trailing slash on the URL is significant.

default Directive

The action taken if the coordinates given do not fit any of thepoly,circle orrect directives, and there are nopoint directives. Defaults tonocontent in the absence of anImapDefault configuration setting, causing a status code of204 No Content to be returned. The client should keep the same page displayed.

poly Directive

Takes three to one-hundred points, and is obeyed if the user selected coordinates fall within the polygon defined by these points.

circle

Takes the center coordinates of a circle and a point on the circle. Is obeyed if the user selected point is with the circle.

rect Directive

Takes the coordinates of two opposing corners of a rectangle. Obeyed if the point selected is within this rectangle.

point Directive

Takes a single point. The point directive closest to the user selected point is obeyed if no other directives are satisfied. Note thatdefault will not be followed if apoint directive is present and valid coordinates are given.

Values

The values for each of the directives can be any of the following:

a URL

The URL can be relative or absolute URL. Relative URLs can contain '..' syntax and will be resolved relative to thebase value.

base itself will not be resolved according to the current value. A statementbase mailto: will work properly, though.

map

Equivalent to the URL of the imagemap file itself. No coordinates are sent with this, so a menu will be generated unlessImapMenu is set tonone.

menu

Synonymous withmap.

referer

Equivalent to the URL of the referring document. Defaults tohttp://servername/ if noReferer: header was present.

nocontent

Sends a status code of204 No Content, telling the client to keep the same page displayed. Valid for all butbase.

error

Fails with a500 Server Error. Valid for all butbase, but sort of silly for anything butdefault.

Coordinates

0,0 200,200

A coordinate consists of anx and ay value separated by a comma. The coordinates are separated from each other by whitespace. To accommodate the way Lynx handles imagemaps, should a user select the coordinate0,0, it is as if no coordinate had been selected.

Quoted Text

"Menu Text"

After the value or after the coordinates, the line optionally may contain text within double quotes. This string is used as the text for the link if a menu is generated:

<a href="http://example.com/">Menu text</a>

If no quoted text is present, the name of the link will be used as the text:

<a href="http://example.com/">http://example.com</a>

If you want to use double quotes within this text, you have to write them as".

Example Mapfile

Referencing your mapfile

ImapBaseDirective

TheImapBase directive sets the defaultbase used in the imagemap files. Its value is overridden by abase directive within the imagemap file. If not present, thebase defaults tohttp://servername/.

See also

• UseCanonicalName

ImapDefaultDirective

TheImapDefault directive sets the defaultdefault used in the imagemap files. Its value is overridden by adefault directive within the imagemap file. If not present, thedefault action isnocontent, which means that a204 No Content is sent to the client. In this case, the client should continue to display the original page.

ImapMenuDirective

TheImapMenu directive determines the action taken if an imagemap file is called without valid coordinates.

none

If ImapMenu isnone, no menu is generated, and thedefault action is performed.

formatted

Aformatted menu is the simplest menu. Comments in the imagemap file are ignored. A level one header is printed, then an hrule, then the links each on a separate line. The menu has a consistent, plain look close to that of a directory listing.

semiformatted

In thesemiformatted menu, comments are printed where they occur in the imagemap file. Blank lines are turned into HTML breaks. No header or hrule is printed, but otherwise the menu is the same as aformatted menu.

unformatted

Comments are printed, blank lines are ignored. Nothing is printed that does not appear in the imagemap file. All breaks and headers must be included as comments in the imagemap file. This gives you the most flexibility over the appearance of your menus, but requires you to treat your map files as HTML instead of plaintext.