Petersham and Ham Sea Scouts Web | PmWiki / Conditional Markup

Syntax

The generic form of the (:if:) directive is

(:if cond param:) body (:if:)

where “cond” names a condition to be tested from the $Conditions array, and “param” is a parameter or other argument held in $condparm in the test. For example, the following (in config.php) adds (:if group GroupName:) as a markup:

$Conditions['group'] = "FmtPageName('\$Group',\$pagename)==\$condparm";

One could then use the following markup:

(:if group PmWiki:) This text only appears in the group “PmWiki”(:if:)

The negated form of (:if:) is automatically handled as well, thus:

(:if ! group PmWiki:) This text appears everywhere *but* in group “PmWiki”(:if:)

Any (:if:) automatically terminates the previous one, thus markup can be easily cased:

(:if group PmWiki:) Do this in PmWiki group

(:if group Main:) Do something else for Main

(:if:) This happens in all groups

See also Cookbook:ExpandingMenus for an example to use this to create compact Sidebar menus.

All that remains now is to come up with a good set of $Conditions. Testing for group membership is a good one, we might also want to create something for generic pagename pattern matches

(:if match ^PmWiki\. :) Only appears in the PmWiki group

(:if match RecentChanges$ :) Everywhere except RecentChanges pages

(:if ! match ^(Main|PmWiki)\. :) All groups except Main and PmWiki

(:if:)again - all groups

There is an (:if auth ...:) conditional markup available for processing depending on the current authorizations in effect. For example, one can create a bullet list with

(:if auth read:)* [[View page -> {$Name}?action=browse]]

(:if auth edit:)* [[Edit page -> {$Name}?action=edit]]

(:if auth upload:)* [[Attachments -> {$Name}?action=upload]]

(:if auth attr:)* [[Page Attributes -> {$Name}?action=attr]]

(:if auth admin:)* You're logged in as admin

(:ifend:)

and only those items corresponding to the user’s current authorizations will appear. This should be very useful in creating action buttons.

$Conditions could also be conditional on other items; e.g., date or time, day of week, etc.

Default PmWiki Conditions

The following are defined in pmwiki.php, so would not need to be defined in config.php:

 
   $Conditions['false'] = 'false';
   $Conditions['true'] = 'true';
   $Conditions['group'] = "FmtPageName('\$Group',\$pagename)==\$condparm";
   $Conditions['name'] = "FmtPageName('\$Name',\$pagename)==\$condparm";
   $Conditions['match'] = 'preg_match("!$condparm!",$pagename)';
   $Conditions['auth'] = '@$GLOBALS["PCache"][$GLOBALS["pagename"]]["=auth"][trim($condparm)]';
   $Conditions['authid'] = '@$GLOBALS["AuthId"] > ""';

Samples for if-markups / `$Conditions`:

(:if group GROUPNAME:) - display following text only, if group = specified groupname:

$Conditions['group'] = "FmtPageName('\$Group',\$pagename)==\$condparm";

(:if author AUTHORNAME:) - display following text only, if author = specified authorname:

$Conditions['author'] = "\$GLOBALS['Author']==\$condparm";

will only work, if Author is “logged” on or has already put his name into the author-field while editing a page, i.e. the global variable $Author must be set

(:if enabled VARIABLE:) - display following text only, if VARIABLE defined in config.php or a skin’s php script is set to 1 or some string value. If set to zero (0), or not set, the condition is not true and the following text will not display:

$Conditions['enabled'] = "(boolean)\$GLOBALS[\$condparm]";

This is useful for instance to have a skin display something, which will be hidden in other skins, by setting a variable in the skin.php file to 1, and checking if the variable is set in the if condition.

Caveat

Q what happens to these kind of things when someone looks at such a page and presses “Show Source”?

 (:if ! auth admin:)
 code seen by other than admins
 (:if auth admin:)
 code seen by admins
 (:if:)

If someone views the HTML source in the browser, then the text isn’t even there — it’s removed from the output entirely by the conditional markup.

However, if someone has read permission to the page and uses ?action=source, they’ll see the entire source including the conditional markups. As per my earlier note, I think I’m going to take the position that PmWiki’s smallest atom of security is the page, and not individual pieces of the page. In other words, (:if …) is a useful way for suppressing parts of a page but not for protecting it.

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Syntax

Default PmWiki Conditions

Samples for if-markups / `$Conditions`:

Caveat

Main.SideBar (edit)

Phoenix Project

Sections

Activities

Equipment

People

Resources

Links

About Wikis

Syntax

Default PmWiki Conditions

Samples for if-markups / $Conditions:

Caveat

Samples for if-markups / `$Conditions`: