TWiki::Func Module Documentation

Official list of stable TWiki functions for Plugin developers

Description

This module defines official funtions that Plugins and add-on scripts can use to interact with the TWiki engine and content.

Plugins should only use functions published in this module. If you use functions in other TWiki libraries you might impose a security hole and you will likely need to change your Plugin when you upgrade TWiki.

Functions: CGI Environment

getSessionValue( $key ) ==> $value

Description:	Get a session value from the Session Plugin (if installed)
Parameter: $key	Session key
Return: $value	Value associated with key; empty string if not set; undef if session plugin is not installed

setSessionValue( $key, $value ) ==> $result

Description:	Set a session value via the Session Plugin (if installed)
Parameter: $key	Session key
Parameter: $value	Value associated with key
Return: $result	"1" if success; undef if session plugin is not installed

getSkin( ) ==> $skin

Description:	Get the name of the skin, set by the SKIN preferences variable or the skin CGI parameter
Return: $skin	Name of skin, e.g. "gnu". Empty string if none

getUrlHost( ) ==> $host

Description:	Get protocol, domain and optional port of script URL
Return: $host	URL host, e.g. "http://example.com:80"

getScriptUrl( $web, $topic, $script ) ==> $url

Description:	Compose fully qualified URL
Parameter: $web	Web name, e.g. "Main"
Parameter: $topic	Topic name, e.g. "WebNotify"
Parameter: $script	Script name, e.g. "view"
Return: $url	URL, e.g. "http://example.com:80/cgi-bin/view.pl/Main/WebNotify"

getScriptUrlPath( ) ==> $path

Description:	Get script URL path
Return: $path	URL path of TWiki scripts, e.g. "/cgi-bin"

getViewUrl( $web, $topic ) ==> $url

Description:	Compose fully qualified view URL
Parameter: $web	Web name, e.g. "Main". The current web is taken if empty
Parameter: $topic	Topic name, e.g. "WebNotify"
Return: $url	URL, e.g. "http://example.com:80/cgi-bin/view.pl/Main/WebNotify"

getOopsUrl( $web, $topic, $template, $param1, $param2, $param3, $param4 ) ==> $url

Description:	Compose fully qualified "oops" dialog URL
Parameter: $web	Web name, e.g. "Main". The current web is taken if empty
Parameter: $topic	Topic name, e.g. "WebNotify"
Parameter: $template	Oops template name, e.g. "oopslocked"
Parameter: $param1 ... $param4	Parameter values for %PARAM1% ... %PARAM4% variables in template, optional
Return: $url	URL, e.g. "http://example.com:80/cgi-bin/oops.pl/ Main/WebNotify?template=oopslocked&param1=joe"

getPubUrlPath( ) ==> $path

Description:	Get pub URL path
Return: $path	URL path of pub directory, e.g. "/pub"

getCgiQuery( ) ==> $query

Description:	Get CGI query object. Important: Plugins cannot assume that scripts run under CGI, Plugins must always test if the CGI query object is set
Return: $query	CGI query object; or 0 if script is called as a shell script

writeHeader( $query )

Description:	Prints a basic content-type HTML header for text/html to standard out
Parameter: $query	CGI query object
Return:	none

redirectCgiQuery( $query, $url )

Description:	Redirect to URL
Parameter: $query	CGI query object
Parameter: $url	URL to redirect to
Return:	none, never returns

Functions: Preferences

extractNameValuePair( $attr, $name ) ==> $value

Description:	Extract a named or unnamed value from a variable parameter string
Parameter: $attr	Attribute string
Parameter: $name	Name, optional
Return: $value	Extracted value

• Example:
  • Variable: %TEST{ "nameless" name1="val1" name2="val2" }%
  • First extract text between {...} to get: "nameless" name1="val1" name2="val2"
  • Then call this on the text:
    my $noname = TWiki::Func::extractNameValuePair( $text );
my $name1  = TWiki::Func::extractNameValuePair( $text, "name1" );
my $name2  = TWiki::Func::extractNameValuePair( $text, "name2" );

getPreferencesValue( $key, $web ) ==> $value

Description:	Get a preferences value from TWiki or from a Plugin
Parameter: $key	Preferences key
Parameter: $web	Name of web, optional. Current web if not specified; does not apply to settings of Plugin topics
Return: $value	Preferences value; empty string if not set

• Example for Plugin setting:
  • MyPlugin topic has: * Set COLOR = red
  • Use "MYPLUGIN_COLOR" for $key
  • my $color = TWiki::Func::getPreferencesValue( "MYPLUGIN_COLOR" );

• Example for preferences setting:
  • WebPreferences topic has: * Set WEBBGCOLOR = #FFFFC0
  • my $webColor = TWiki::Func::getPreferencesValue( "WEBBGCOLOR", "Sandbox" );

getPreferencesFlag( $key, $web ) ==> $value

Description:	Get a preferences flag from TWiki or from a Plugin
Parameter: $key	Preferences key
Parameter: $web	Name of web, optional. Current web if not specified; does not apply to settings of Plugin topics
Return: $value	Preferences flag "1" (if set), or "0" (for preferences values "off", "no" and "0")

• Example for Plugin setting:
  • MyPlugin topic has: * Set SHOWHELP = off
  • Use "MYPLUGIN_SHOWHELP" for $key
  • my $showHelp = TWiki::Func::getPreferencesFlag( "MYPLUGIN_SHOWHELP" );

getWikiToolName( ) ==> $name

Description:	Get toolname as defined in TWiki.cfg
Return: $name	Name of tool, e.g. "TWiki"

getMainWebname( ) ==> $name

Description:	Get name of Main web as defined in TWiki.cfg
Return: $name	Name, e.g. "Main"

getTwikiWebname( ) ==> $name

Description:	Get name of TWiki documentation web as defined in TWiki.cfg
Return: $name	Name, e.g. "TWiki"

Functions: User Handling and Access Control

getDefaultUserName( ) ==> $loginName

Description:	Get default user name as defined in TWiki.cfg's $defaultUserName
Return: $loginName	Default user name, e.g. "guest"

getWikiName( ) ==> $wikiName

Description:	Get Wiki name of logged in user
Return: $wikiName	Wiki Name, e.g. "JohnDoe"

getWikiUserName( $text ) ==> $wikiName

Description:	Get Wiki name of logged in user with web prefix
Return: $wikiName	Wiki Name, e.g. "Main.JohnDoe"

wikiToUserName( $wikiName ) ==> $loginName

Description:	Translate a Wiki name to a login name based on Main.TWikiUsers topic
Parameter: $wikiName	Wiki name, e.g. "Main.JohnDoe" or "JohnDoe"
Return: $loginName	Login name of user, e.g. "jdoe"

userToWikiName( $loginName, $dontAddWeb ) ==> $wikiName

Description:	Translate a login name to a Wiki name based on Main.TWikiUsers topic
Parameter: $loginName	Login name, e.g. "jdoe"
Parameter: $dontAddWeb	Do not add web prefix if "1"
Return: $wikiName	Wiki name of user, e.g. "Main.JohnDoe" or "JohnDoe"

isGuest( ) ==> $flag

Description:	Test if logged in user is a guest
Return: $flag	"1" if yes, "0" if not

permissionsSet( $web ) ==> $flag

Description:	Test if any access restrictions are set for this web, ignoring settings on individual pages
Parameter: $web	Web name, required, e.g. "Sandbox"
Return: $flag	"1" if yes, "0" if no

checkAccessPermission( $type, $wikiName, $text, $topic, $web ) ==> $flag

Description:	Check access permission for a topic based on the TWiki.TWikiAccessControl rules
Parameter: $type	Access type, e.g. "VIEW", "CHANGE", "CREATE"
Parameter: $wikiName	WikiName of remote user, i.e. "Main.PeterThoeny"
Parameter: $text	Topic text, optional. If empty, topic $web.$topic is consulted
Parameter: $topic	Topic name, required, e.g. "PrivateStuff"
Parameter: $web	Web name, required, e.g. "Sandbox"
Return: $flag	"1" if access may be granted, "0" if not

Functions: Content Handling

webExists( $web ) ==> $flag

Description:	Test if web exists
Parameter: $web	Web name, required, e.g. "Sandbox"
Return: $flag	"1" if web exists, "0" if not

topicExists( $web, $topic ) ==> $flag

Description:	Test if topic exists
Parameter: $web	Web name, optional, e.g. "Main"
Parameter: $topic	Topic name, required, e.g. "TokyoOffice", or "Main.TokyoOffice"
Return: $flag	"1" if topic exists, "0" if not

getRevisionInfo( $web, $topic ) ==> ( $date, $loginName, $rev )

Description:	Get revision info of a topic
Parameter: $web	Web name, optional, e.g. "Main"
Parameter: $topic	Topic name, required, e.g. "TokyoOffice"
Return: ( $date, $loginName, $rev )	List with: ( last update date, login name of last user, minor part of top revision number ), e.g. ( "01 Jan 2003", "phoeny", "5" )

checkTopicEditLock( $web, $topic ) ==> ( $oopsUrl, $loginName, $unlockTime )

Description:	Check if topic has an edit lock by a user
Parameter: $web	Web name, e.g. "Main", or empty
Parameter: $topic	Topic name, e.g. "MyTopic", or "Main.MyTopic"
Return: ( $oopsUrl, $loginName, $unlockTime )	The $oopsUrl for calling redirectCgiQuery(), user's $loginName, and estimated $unlockTime in minutes. The $oopsUrl and $loginName is empty if topic has no edit lock.

setTopicEditLock( $web, $topic, $lock ) ==> $oopsUrl

Description:	Lock topic for editing, or unlock when done
Parameter: $web	Web name, e.g. "Main", or empty
Parameter: $topic	Topic name, e.g. "MyTopic", or "Main.MyTopic"
Parameter: $lock	Set to 1 to lock topic, 0 to unlock
Return: $oopsUrl	Empty string if OK; the $oopsUrl for calling redirectCgiQuery() in case lock is already taken when trying to lock topic

readTopicText( $web, $topic, $rev, $ignorePermissions ) ==> $text

Description:	Read topic text, including meta data
Parameter: $web	Web name, e.g. "Main", or empty
Parameter: $topic	Topic name, e.g. "MyTopic", or "Main.MyTopic"
Parameter: $rev	Topic revision to read, optional. Specify the minor part of the revision, e.g. "5", not "1.5"; the top revision is returned if omitted or empty.
Parameter: $ignorePermissions	Set to "1" if checkAccessPermission() is already performed and OK; an oops URL is returned if user has no permission
Return: $text	Topic text with embedded meta data; an oops URL for calling redirectCgiQuery() is returned in case of an error

saveTopicText( $web, $topic, $text, $ignorePermissions, $dontNotify ) ==> $oopsUrl

Description:	Save topic text, typically obtained by readTopicText(). Topic data usually includes meta data; the file attachment meta data is replaced by the meta data from the topic file if it exists.
Parameter: $web	Web name, e.g. "Main", or empty
Parameter: $topic	Topic name, e.g. "MyTopic", or "Main.MyTopic"
Parameter: $text	Topic text to save, assumed to include meta data
Parameter: $ignorePermissions	Set to "1" if checkAccessPermission() is already performed and OK
Parameter: $dontNotify	Set to "1" if not to notify users of the change
Return: $oopsUrl	Empty string if OK; the $oopsUrl for calling redirectCgiQuery() in case of error

• Example:
  my $oopsUrl = TWiki::Func::setTopicEditLock( $web, $topic, 1 );
if( $oopsUrl ) {
    TWiki::Func::redirectCgiQuery( $query, $oopsUrl );   # assuming valid query
    return;
}
my $text = TWiki::Func::readTopicText( $web, $topic );        # read topic text
# check for oops URL in case of error:
if( $text =~ /^http.*?\/oops/ ) {
    TWiki::Func::redirectCgiQuery( $query, $text );
    return;
}
# do topic text manipulation like:
$text =~ s/old/new/g;
# do meta data manipulation like:
$text =~ s/(META\:FIELD.*?name\=\"TopicClassification\".*?value\=\")[^\"]*/$1BugResolved/;
$oopsUrl = TWiki::Func::saveTopicText( $web, $topic, $text ); # save topic text
TWiki::Func::setTopicEditLock( $web, $topic, 0 );             # unlock topic
if( $oopsUrl ) {
    TWiki::Func::redirectCgiQuery( $query, $oopsUrl );
    return;
}

getPublicWebList( ) ==> @webs

Description:	Get list of all public webs, e.g. all webs that do not have the NOSEARCHALL flag set in the WebPreferences
Return: @webs	List of all public webs, e.g. ( "Main",  "Know", "TWiki" )

getTopicList( $web ) ==> @topics

Description:	Get list of all topics in a web
Parameter: $web	Web name, required, e.g. "Sandbox"
Return: @topics	Topic list, e.g. ( "WebChanges",  "WebHome", "WebIndex", "WebNotify" )

Functions: Rendering

expandCommonVariables( $text, $topic, $web ) ==> $text

Description:	Expand all common %VARIABLES%
Parameter: $text	Text with variables to expand, e.g. "Current user is %WIKIUSER%"
Parameter: $topic	Current topic name, e.g. "WebNotify"
Parameter: $web	Web name, optional, e.g. "Main". The current web is taken if missing
Return: $text	Expanded text, e.g. "Current user is TWikiGuest"

renderText( $text, $web ) ==> $text

Description:	Render text from TWiki markup into XHTML as defined in TWiki.TextFormattingRules
Parameter: $text	Text to render, e.g. "*bold* text and =fixed font="
Parameter: $web	Web name, optional, e.g. "Main". The current web is taken if missing
Return: $text	XHTML text, e.g. "<b>bold</b> and <code>fixed font</code>"

internalLink( $pre, $web, $topic, $label, $anchor, $createLink ) ==> $text

Description:	Render topic name and link label into an XHTML link. Normally you do not need to call this funtion, it is called internally by renderText()
Parameter: $pre	Text occuring before the TWiki link syntax, optional
Parameter: $web	Web name, required, e.g. "Main"
Parameter: $topic	Topic name to link to, required, e.g. "WebNotify"
Parameter: $label	Link label, required. Usually the same as $topic, e.g. "notify"
Parameter: $anchor	Anchor, optional, e.g. "#Jump"
Parameter: $createLink	Set to "1" to add question linked mark after topic name if topic does not exist; set to "0" to suppress link for non-existing topics
Return: $text	XHTML anchor, e.g. "<a href="/cgi-bin/view/Main/WebNotify#Jump">notify</a>"

search text( $text ) ==> $text

Description:	This is not a function, just a how-to note. Use: expandCommonVariables("%SEARCH{...}%" );
Parameter: $text	Search variable
Return: "$text"	Search result in TWiki.FormattedSearch format

formatGmTime( $time, $format ) ==> $text

Description:	Format the time to GM time
Parameter: $time	Time in epoc seconds
Parameter: $format	Format type, optional. Default e.g. "31 Dec 2002 - 19:30", can be "iso" (e.g. "2002-12-31T19:30Z"), "rcs" (e.g. "2001/12/31 23:59:59", "http" for HTTP header format (e.g. "Thu, 23 Jul 1998 07:21:56 GMT")
Return: $text	Formatted time string

Functions: File I/O

getDataDir( ) ==> $dir

Description:	Get data directory (topic file root)
Return: $dir	Data directory, e.g. "/twiki/data"

getPubDir( ) ==> $dir

Description:	Get pub directory (file attachment root). Attachments are in $dir/Web/TopicName
Return: $dir	Pub directory, e.g. "/htdocs/twiki/pub"

readTemplate( $name, $skin ) ==> $text

Description:	Read a template or skin file. Embedded template directives get expanded
Parameter: $name	Template name, e.g. "view"
Parameter: $skin	Skin name, optional, e.g. "print"
Return: $text	Template text

readFile( $filename ) ==> $text

Description:	Read text file, low level. NOTE: For topics use readTopicText()
Parameter: $filename	Full path name of file
Return: $text	Content of file

saveFile( $filename, $text )

Description:	Save text file, low level. NOTE: For topics use saveTopicText()
Parameter: $filename	Full path name of file
Parameter: $text	Text to save
Return:	none

writeWarning( $text )

Description:	Log Warning that may require admin intervention to data/warning.txt
Parameter: $text	Text to write; timestamp gets added
Return:	none

writeDebug( $text )

Description:	Log debug message to data/debug.txt
Parameter: $text	Text to write; timestamp gets added
Return:	none

Copyright and License

Copyright (C) 2000-2003 Peter Thoeny, Peter@Thoeny*-r-e-m-o-v-e-*.com

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details, published at http://www.gnu.org/copyleft/gpl.html

NOTE: Above text is copied from the TWiki::Plugins/PerlDocPlugin output of TWiki::Func in twiki format. In case you want to get dynamically updated documentation based on the actual Perl module, install the PerlDocPlugin and replace above text with %PERLDOC{"TWiki::Func"}%.

-- PeterThoeny - 31 Dec 2002