Flexible handling of topic variables
The main purpose of this plugin is to allow to set topic variables when saving a topic. Url parameters posted to
save will be parsed and stored into the current topic.
Parameters must have the form:
Local+<key>=<value> will create a local topic variable called
key with value =value
Set+<key>=<value> will create a normal topic variable called
key with value =value (note if stored in a user topic these take effect on all of the site for this user; see the Foswiki documentation for a more in depth explanation)
Unset+<key>=<value> will remove a topic variable called
key from the topic
Default+<key>=<value> defines the default values for a variable
key is set to this value, it will actually be remove from the topic as it is being set to a default value
In addition to setting topic variables via url parameters of a
save action, this plugin provides means to read and write topic variables in WikiApplications. Among other use cases these can be used to create appropriate html forms for topic variables as far as the function is not provided by standard TML part of the Foswiki core.
When SETVAR and UNSERVAR are parsed during the discourse of creating the current page they don't set the topic variable immediately. Instead they create a definition rule. All definition rules are collected and applied to the topic at the end of the parsing process. That way multiple SETVAR and UNSERVAR - that potentially contradict each other - stack up. The last rule on the stack wins and decides wether a variable is set or deleted. This allows to create more extensive rule sets.
This sets topic variable
key to value
value if the formfield
fieldname of the current topic matches
pattern. This allows to set topic variables based on the value of a formfield value. For example, that's useful to create access control settings automatically.
This unsets topic variable
key when formfield formfield
fieldname of the current topic matches
This displays a variable
key as stored in topic
web.topic and formats it using the given
format. It's type can be any of the known Foswiki meta data specifies like
TOPICINFO etc. When no definition of
key was found the
default value is returned. Instead of extracting a variable from
web.topic it can also be extracted from a specific scope.
Normally all scopes are layered above each other and only the value defined in the scope with highest precedence is returned. So when ever a variable is set in a topic, it will potentially override its definition on web level or user level. You may use the
scope parameter to bypass this logic and extract a specific value from the given scope specifier.
Multiple variables can be returned by one call if you use a
pattern instead of a
key holding a regular expression. GETVAR will return all variable values of the given
type where the
pattern matches on the variable name. The list of variables will be displayed using
format preceded by
header and appended by
footer will be omitted when no matching variable was found.
format string may contain the standard escape parameters
$n as well as
$value - the value of the current variable
$name - the name of the current variable
$title - the title and the
$type - which is
Session depending on the type and scope of the variable
Display a table of all definition rules as far as collected by SETVAR and UNSERVAR.
You do not need to install anything in the browser to use this extension. The following instructions are for the administrator who installs the extension on the server.
Open configure, and open the "Extensions" section. Use "Find More Extensions" to get a list of available extensions. Select "Install".
If you have any problems, or if the extension isn't available in
configure, then you can still install manually from the command-line. See http://foswiki.org/Support/ManuallyInstallingExtensions for more help.