Пункт 149. Apache Module mod_imagemap
Description: | Server-side imagemap processing |
Status: | Base |
Module Identifier: | imagemap_module |
Source File: | mod_imagemap.c |
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Summary
This module processes .map
files, thereby
replacing the functionality of the imagemap
CGI
program. Any directory or document type configured to use the
handler imap-file
(using either
AddHandler
or
SetHandler
)
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.
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
directive base
.
- No need for
imagemap.conf
file.
- Point references.
- Configurable generation of imagemap menus.
Imagemap File
The lines in the imagemap files can have one of several
formats:
directive value [x,y ...]
directive value "Menu text" [x,y
...]
directive value x,y ... "Menu text"
The directive is one of base
,
default
, poly
, circle
,
rect
, or point
. The value is an
absolute or relative URL, or one of the special values listed
below. The coordinates are x,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. The base
directive overrides
ImapBase
as set in a
.htaccess
file or in the server configuration files.
In the absence of an ImapBase
configuration
directive, base
defaults to
http://server_name/
.
base_uri
is synonymous with base
.
Note that a trailing slash on the URL is significant.
-
default
Directive
- The action taken if the coordinates given do not fit any
of the
poly
, circle
or
rect
directives, and there are no
point
directives. Defaults to nocontent
in the absence of an ImapDefault
configuration setting, causing a status
code of 204 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 that
default
will not be
followed if a point
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 the
base
value.
base
itself will not be resolved according to the
current value. A statement base 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
unless
ImapMenu
is set to
none
.
-
menu
- Synonymous with
map
.
-
referer
- Equivalent to the URL of the referring document. Defaults
to
http://servername/
if no Referer:
header was present.
-
nocontent
- Sends a status code of
204 No Content
,
telling the client to keep the same page displayed. Valid for
all but base
.
-
error
- Fails with a
500 Server Error
. Valid for all
but base
, but sort of silly for anything but
default
.
Coordinates
-
0,0 200,200
- A coordinate consists of an x and a y
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 coordinate
0,0
, 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
#Comments are printed in a 'formatted' or 'semiformatted' menu.
#And can contain html tags. <hr>
base referer
poly map "Could I have a menu, please?" 0,0 0,10 10,10 10,0
rect .. 0,0 77,27 "the directory of the referer"
circle http://www.inetnebr.example.com/lincoln/feedback/ 195,0 305,27
rect another_file "in same directory as referer" 306,0 419,27
point http://www.zyzzyva.example.com/ 100,100
point http://www.tripod.example.com/ 200,200
rect mailto:nate@tripod.example.com 100,150 200,0 "Bugs?"
Referencing your mapfile
HTML example
<a href="/maps/imagemap1.map">
<img ismap src="/images/imagemap1.gif">
</a>
XHTML example
<a href="/maps/imagemap1.map">
<img ismap="ismap" src="/images/imagemap1.gif" />
</a>
ImapBase Directive
Description: | Default base for imagemap files |
Syntax: | ImapBase map|referer|URL |
Default: | ImapBase http://servername/ |
Context: | server config, virtual host, directory, .htaccess |
Override: | Indexes |
Status: | Base |
Module: | mod_imagemap |
The ImapBase
directive sets the default
base
used in the imagemap files. Its value is
overridden by a base
directive within the imagemap
file. If not present, the base
defaults to
http://servername/
.
See also
ImapDefault Directive
Description: | Default action when an imagemap is called with coordinates
that are not explicitly mapped |
Syntax: | ImapDefault error|nocontent|map|referer|URL |
Default: | ImapDefault nocontent |
Context: | server config, virtual host, directory, .htaccess |
Override: | Indexes |
Status: | Base |
Module: | mod_imagemap |
The ImapDefault
directive sets the default
default
used in the imagemap files. Its value is
overridden by a default
directive within the
imagemap file. If not present, the default
action
is nocontent
, which means that a 204 No
Content
is sent to the client. In this case, the client
should continue to display the original page.
ImapMenu Directive
Description: | Action if no coordinates are given when calling
an imagemap |
Syntax: | ImapMenu none|formatted|semiformatted|unformatted |
Default: | ImapMenu formatted |
Context: | server config, virtual host, directory, .htaccess |
Override: | Indexes |
Status: | Base |
Module: | mod_imagemap |
The ImapMenu
directive determines the
action taken if an imagemap file is called without valid
coordinates.
-
none
- If ImapMenu is
none
, no menu is generated,
and the default
action is performed.
-
formatted
- A
formatted
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 the
semiformatted
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 a
formatted
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.