template::plugins(3)

NAME

Template::Plugins - Plugin provider module

SYNOPSIS

use Template::Plugins;
$plugin_provider = Template::Plugins->new(options);
($plugin,  $error)  =   $plugin_provider->fetch($name,
@args);

DESCRIPTION

The Template::Plugins module defines a provider class
which can be used to load and instantiate Template Toolkit
plugin modules.

METHODS

new%(params)

Constructor method which instantiates and returns a refer
ence to a Template::Plugins object. A reference to a hash
array of configuration items may be passed as a parameter.
These are described below.

Note that the Template.pm front-end module creates a Tem plate::Plugins provider, passing all configuration items. Thus, the examples shown below in the form:: $plugprov = Template::Plugins->new({
PLUGIN_BASE => 'MyTemplate::Plugin',
LOAD_PERL => 1,
...; });
can also be used via the Template module as:: $ttengine = Template->new({
PLUGIN_BASE => 'MyTemplate::Plugin',
LOAD_PERL => 1,
...; });
as well as the more explicit form of:: $plugprov = Template::Plugins->new({
PLUGIN_BASE => 'MyTemplate::Plugin',
LOAD_PERL => 1,
...; });; $ttengine = Template->new({
LOAD_PLUGINS => [ $plugprov ],; });
fetch($name, @args)
Called to request that a plugin of a given name be pro vided. The relevant module is first loaded (if necessary) and the load() class method called to return the factory class name (usually the same package name) or a factory object (a prototype). The new() method is then called as a class or object method against the factory, passing all remaining parameters.
Returns a reference to a new plugin object or ($error, STATUS_ERROR) on error. May also return (undef, STA TUS_DECLINED) to decline to serve the request. If TOLER ANT is set then all errors will be returned as declines.

CONFIGURATION OPTIONS

The following list details the configuration options that
can be provided to the Template::Plugins new() construc
tor.

PLUGINS: The PLUGINS options can be used to provide a reference
to a hash array that maps plugin names to Perl module
names. A number of standard plugins are defined (e.g.
'table', 'cgi', 'dbi', etc.) which map to their corre
sponding Template::Plugin::* counterparts. These can
be redefined by values in the PLUGINS hash.

my $plugins = Template::Plugins->new({
PLUGINS => {
cgi => 'MyOrg::Template::Plugin::CGI',
foo => 'MyOrg::Template::Plugin::Foo',
bar => 'MyOrg::Template::Plugin::Bar',

},

});; The USE directive is used to create plugin objects and
does so by calling the plugin() method on the current Template::Context object. If the plugin name is
defined in the PLUGINS hash then the corresponding
Perl module is loaded via require(). The context then calls the load() class method which should return the
class name (default and general case) or a prototype
object against which the new() method can be called to
instantiate individual plugin objects.; If the plugin name is not defined in the PLUGINS hash
then the PLUGIN_BASE and/or LOAD_PERL options come
into effect.
PLUGIN_BASE: If a plugin is not defined in the PLUGINS hash then
the PLUGIN_BASE is used to attempt to construct a cor
rect Perl module name which can be successfully
loaded.; The PLUGIN_BASE can be specified as a single value or
as a reference to an array of multiple values. The
default PLUGIN_BASE value, 'Template::Plugin', is
always added the the end of the PLUGIN_BASE list (a
single value is first converted to a list). Each
value should contain a Perl package name to which the
requested plugin name is appended.; example 1:

my $plugins = Template::Plugins->new({
PLUGIN_BASE => 'MyOrg::Template::Plugin',

});

[% USE Foo %] # => MyOrg::Template::Plugin::Foo

or Template::Plugin::Foo
example 2:: my $plugins = Template::Plugins->new({
PLUGIN_BASE => [ 'MyOrg::Template::Plugin',
'YourOrg::Template::Plugin'

],

});

[% USE Foo %] # => MyOrg::Template::Plug

in::Foo

or YourOrg::Template::Plug

in::Foo
or Template::Plug

in::Foo
LOAD_PERL: If a plugin cannot be loaded using the PLUGINS or PLU
GIN_BASE approaches then the provider can make a final
attempt to load the module without prepending any pre
fix to the module path. This allows regular Perl mod
ules (i.e. those that don't reside in the Tem
plate::Plugin or some other such namespace) to be
loaded and used as plugins.; By default, the LOAD_PERL option is set to 0 and no
attempt will be made to load any Perl modules that
aren't named explicitly in the PLUGINS hash or reside
in a package as named by one of the PLUGIN_BASE compo
nents.; Plugins loaded using the PLUGINS or PLUGIN_BASE
receive a reference to the current context object as
the first argument to the new() constructor. Modules
loaded using LOAD_PERL are assumed to not conform to
the plugin interface. They must provide a new() class
method for instantiating objects but it will not
receive a reference to the context as the first argu
ment. Plugin modules should provide a load() class
method (or inherit the default one from the Tem
plate::Plugin base class) which is called the first
time the plugin is loaded. Regular Perl modules need
not. In all other respects, regular Perl objects and
Template Toolkit plugins are identical.; If a particular Perl module does not conform to the
common, but not unilateral, new() constructor conven
tion then a simple plugin wrapper can be written to
interface to it.
TOLERANT: The TOLERANT flag is used by the various Template
Toolkit provider modules (Template::Provider, Tem
plate::Plugins, Template::Filters) to control their
behaviour when errors are encountered. By default,
any errors are reported as such, with the request for
the particular resource (template, plugin, filter)
being denied and an exception raised. When the TOLER
ANT flag is set to any true values, errors will be
silently ignored and the provider will instead return
STATUS_DECLINED. This allows a subsequent provider to
take responsibility for providing the resource, rather
than failing the request outright. If all providers
decline to service the request, either through toler
ated failure or a genuine disinclination to comply,
then a '<resource> not found' exception is raised.

TEMPLATE TOOLKIT PLUGINS

The following plugin modules are distributed with the Tem
plate Toolkit. Some of the plugins interface to external
modules (detailed below) which should be downloaded from
any CPAN site and installed before using the plugin.

Autoformat

The Autoformat plugin is an interface to Damian Conway's Text::Autoformat Perl module which provides advanced text wrapping and formatting. See Template::Plugin::Autoformat and Text::Autoformat for further details.: [% USE autoformat(left=10, right=20) %]
[% autoformat(mytext) %] # call autoformat sub
[% mytext FILTER autoformat %] # or use autoformat; filter
The Text::Autoformat module is available from CPAN:: http://www.cpan.org/modules/by-module/Text/
CGI
The CGI plugin is a wrapper around Lincoln Stein's <lstein@genome.wi.mit.edu> CGI.pm module. The plugin is distributed with the Template Toolkit (see Template::Plu gin::CGI) and the CGI module itself is distributed with recent versions Perl, or is available from CPAN.: [% USE CGI %]
[% CGI.param('param_name') %]
[% CGI.start_form %]
[% CGI.popup_menu( Name => 'color',
Values => [ 'Green', 'Brown' ] ) %]; [% CGI.end_form %]
Datafile
Provides an interface to data stored in a plain text file in a simple delimited format. The first line in the file specifies field names which should be delimiter by any non-word character sequence. Subsequent lines define data using the same delimiter as int he first line. Blank lines and comments (lines starting '#') are ignored. See Template::Plugin::Datafile for further details.
/tmp/mydata:: # define names for each field
id : email : name : tel
# here's the data
fred : fred@here.com : Fred Smith : 555-1234
bill : bill@here.com : Bill White : 555-5678
example:: [% USE userlist = datafile('/tmp/mydata') %]; [% FOREACH user = userlist %]
[% user.name %] ([% user.id %]); [% END %]
Date
The Date plugin provides an easy way to generate formatted time and date strings by delegating to the POSIX strf_ time() routine. See Template::Plugin::Date and POSIX for further details.: [% USE date %]
[% date.format %] # current time/date; File last modified: [% date.format(template.modtime); %]
Directory
The Directory plugin provides a simple interface to a directory and the files within it. See Template::Plu gin::Directory for further details.: [% USE dir = Directory('/tmp') %]
[% FOREACH file = dir.files %]
# all the plain files in the directory; [% END %]
[% FOREACH file = dir.dirs %]
# all the sub-directories; [% END %]
DBI
The DBI plugin, developed by Simon Matthews <sam@knowl edgepool.com>, brings the full power of Tim Bunce's <Tim.Bunce@ig.co.uk> database interface module (DBI) to your templates. See Template::Plugin::DBI and DBI for further details.: [% USE DBI('dbi:driver:database', 'user', 'pass') %]; [% FOREACH user = DBI.query( 'SELECT * FROM users' ); %]
[% user.id %] [% user.name %]; [% END %]
The DBI and relevant DBD modules are available from CPAN:: http://www.cpan.org/modules/by-module/DBI/
Dumper
The Dumper plugin provides an interface to the Data::Dumper module. See Template::Plugin::Dumper and Data::Dumper for futher details.: [% USE dumper(indent=0, pad="<br>") %]
[% dumper.dump(myvar, yourvar) %]
File
The File plugin provides a general abstraction for files and can be used to fetch information about specific files within a filesystem. See Template::Plugin::File for fur ther details.: [% USE File('/tmp/foo.html') %]
[% File.name %] # foo.html
[% File.dir %] # /tmp
[% File.mtime %] # modification time
Filter
This module implements a base class plugin which can be subclassed to easily create your own modules that define and install new filters.: package MyOrg::Template::Plugin::MyFilter;; use Template::Plugin::Filter;
use base qw( Template::Plugin::Filter );; sub filter {
my ($self, $text) = @_;

# ...mungify $text...

return $text;; }; # now load it...
[% USE MyFilter %]; # ...and use the returned object as a filter
[% FILTER $MyFilter %]
...; [% END %]
See Template::Plugin::Filter for further details.
Format
The Format plugin provides a simple way to format text according to a printf()-like format. See Template::Plu gin::Format for further details.: [% USE bold = format('<b>%s</b>') %]
[% bold('Hello') %]
GD::Image, GD::Polygon, GD::Constants
These plugins provide access to the GD graphics library via Lincoln D. Stein's GD.pm interface. These plugins allow PNG, JPEG and other graphical formats to be gener ated.: [% FILTER null;
USE im = GD.Image(100,100);
# allocate some colors
black = im.colorAllocate(0, 0, 0);
red = im.colorAllocate(255,0, 0);
blue = im.colorAllocate(0, 0, 255);
# Draw a blue oval
im.arc(50,50,95,75,0,360,blue);
# And fill it with red
im.fill(50,50,red);
# Output image in PNG format
im.png | stdout(1);; END;
-%]
See Template::Plugin::GD::Image for further details.
GD::Text, GD::Text::Align, GD::Text::Wrap
These plugins provide access to Martien Verbruggen's GD::Text, GD::Text::Align and GD::Text::Wrap modules. These plugins allow the layout, alignment and wrapping of text when drawing text in GD images.: [% FILTER null;
USE gd = GD.Image(200,400);
USE gdc = GD.Constants;
black = gd.colorAllocate(0, 0, 0);
green = gd.colorAllocate(0, 255, 0);
txt = "This is some long text. " | repeat(10);
USE wrapbox = GD.Text.Wrap(gd,
line_space => 4,
color => green,
text => txt,

);
wrapbox.set_font(gdc.gdMediumBoldFont);
wrapbox.set(align => 'center', width => 160);
wrapbox.draw(20, 20);
gd.png | stdout(1);; END;
-%]
See Template::Plugin::GD::Text, Template::Plu gin::GD::Text::Align and Template::Plugin::GD::Text::Wrap for further details.
GD::Graph::lines, GD::Graph::bars, GD::Graph::points, GD::Graph::linespoin ts, GD::Graph::area, GD::Graph::mixed, GD::Graph::pie
These plugins provide access to Martien Verbruggen's GD::Graph module that allows graphs, plots and charts to be created. These plugins allow graphs, plots and charts to be generated in PNG, JPEG and other graphical formats.: [% FILTER null;
data = [
["1st","2nd","3rd","4th","5th","6th"],
[ 4, 2, 3, 4, 3, 3.5]

];
USE my_graph = GD.Graph.pie(250, 200);
my_graph.set(

title => 'A Pie Chart',
label => 'Label',
axislabelclr => 'black',
pie_height => 36,
transparent => 0,

);
my_graph.plot(data).png | stdout(1);; END;
-%]
See Template::Plugin::GD::Graph::lines, Template::Plu gin::GD::Graph::bars, Template::Plugin::GD::Graph::points, Template::Plugin::GD::Graph::linespoints, Template::Plu gin::GD::Graph::area, Template::Plugin::GD::Graph::mixed, Template::Plugin::GD::Graph::pie, and GD::Graph, for more details.
GD::Graph::bars3d, GD::Graph::lines3d, GD::Graph::pie3d
These plugins provide access to Jeremy Wadsack's GD::Graph3d module. This allows 3D bar charts and 3D lines plots to be generated.: [% FILTER null;
data = [
["1st","2nd","3rd","4th","5th","6th","7th",

"8th", "9th"],
[ 1, 2, 5, 6, 3, 1.5, 1,

3, 4],

];
USE my_graph = GD.Graph.bars3d();
my_graph.set(

x_label => 'X Label',
y_label => 'Y label',
title => 'A 3d Bar Chart',
y_max_value => 8,
y_tick_number => 8,
y_label_skip => 2,
# shadows
bar_spacing => 8,
shadow_depth => 4,
shadowclr => 'dred',
transparent => 0,

my_graph.plot(data).png | stdout(1);; END;
-%]
See Template::Plugin::GD::Graph::lines3d, Template::Plu gin::GD::Graph::bars3d, and Template::Plu gin::GD::Graph::pie3d for more details.
HTML
The HTML plugin is very new and very basic, implementing a few useful methods for generating HTML. It is likely to be extended in the future or integrated with a larger pro ject to generate HTML elements in a generic way (as dis cussed recently on the mod_perl mailing list).: [% USE HTML %]
[% HTML.escape("if (a < b && c > d) ..." %]
[% HTML.attributes(border => 1, cellpadding => 2) %]
[% HTML.element(table => { border => 1, cellpadding =>; 2 }) %]
See Template::Plugin::Iterator for further details.
Iterator
The Iterator plugin provides a way to create a Tem plate::Iterator object to iterate over a data set. An iterator is created automatically by the FOREACH directive and is aliased to the 'loop' variable. This plugin allows an iterator to be explicitly created with a given name, or the default plugin name, 'iterator'. See Template::Plu gin::Iterator for further details.: [% USE iterator(list, args) %]; [% FOREACH item = iterator %]
[% '<ul>' IF iterator.first %]
<li>[% item %]
[% '</ul>' IF iterator.last %]; [% END %]
Pod
This plugin provides an interface to the Pod::POD module which parses POD documents into an internal object model which can then be traversed and presented through the Tem plate Toolkit.: [% USE Pod(podfile) %]; [% FOREACH head1 = Pod.head1;
FOREACH head2 = head1/head2;
...

END;; END
%]
String
The String plugin implements an object-oriented interface for manipulating strings. See Template::Plugin::String for further details.: [% USE String 'Hello' %]
[% String.append(' World') %]; [% msg = String.new('Another string') %]
[% msg.replace('string', 'text') %]; The string "[% msg %]" is [% msg.length %] characters; long.
Table
The Table plugin allows you to format a list of data items into a virtual table by specifying a fixed number of rows or columns, with an optional overlap. See Template::Plu gin::Table for further details.: [% USE table(list, rows=10, overlap=1) %]; [% FOREACH item = table.col(3) %]
[% item %]; [% END %]
URL
The URL plugin provides a simple way of contructing URLs from a base part and a variable set of parameters. See Template::Plugin::URL for further details.: [% USE mycgi = url('/cgi-bin/bar.pl', debug=1) %]; [% mycgi %]
# ==> /cgi/bin/bar.pl?debug=1; [% mycgi(mode='submit') %]
# ==> /cgi/bin/bar.pl?mode=submit&debug=1; Wrap; The Wrap plugin uses the Text::Wrap module by David Muir
Sharnoff <muir@idiom.com> (with help from Tim Pierce and
many many others) to provide simple paragraph formatting.
See Template::Plugin::Wrap and Text::Wrap for further
details.

[% USE wrap %]
[% wrap(mytext, 40, '* ', ' ') %] # use wrap sub
[% mytext FILTER wrap(40) -%] # or wrap FILTER; The Text::Wrap module is available from CPAN:

http://www.cpan.org/modules/by-module/Text/; XML::DOM; The XML::DOM plugin gives access to the XML Document
Object Module via Clark Cooper <cooper@sch.ge.com> and
Enno Derksen's <enno@att.com> XML::DOM module. See Tem
plate::Plugin::XML::DOM and XML::DOM for further details.

[% USE dom = XML.DOM %]
[% doc = dom.parse(filename) %]

[% FOREACH node = doc.getElementsByTagName('CODEBASE')

%]
* [% node.getAttribute('href') %]

[% END %]; The plugin requires the XML::DOM module, available from
CPAN:

http://www.cpan.org/modules/by-module/XML/; XML::RSS; The XML::RSS plugin is a simple interface to Jonathan
Eisenzopf's <eisen@pobox.com> XML::RSS module. A RSS
(Rich Site Summary) file is typically used to store short
news 'headlines' describing different links within a site.
This plugin allows you to parse RSS files and format the
contents accordingly using templates. See Template::Plu
gin::XML::RSS and XML::RSS for further details.

[% USE news = XML.RSS(filename) %]

[% FOREACH item = news.items %]
<a href="[% item.link %]">[% item.title %]</a>

[% END %]; The XML::RSS module is available from CPAN:

http://www.cpan.org/modules/by-module/XML/; XML::Simple; This plugin implements an interface to the XML::Simple
module.

[% USE xml = XML.Simple(xml_file_or_text) %]

[% xml.head.title %]; See Template::Plugin::XML::Simple for further details.; XML::Style; This plugin defines a filter for performing simple
stylesheet based transformations of XML text.

[% USE xmlstyle
table = {
attributes = {
border = 0
cellpadding = 4
cellspacing = 1

}

}

%]

[% FILTER xmlstyle %]
<table>
<tr>

<td>Foo</td> <td>Bar</td> <td>Baz</td>

</tr>
</table>
[% END %]; See Template::Plugin::XML::Style for further details.; XML::XPath; The XML::XPath plugin provides an interface to Matt
Sergeant's <matt@sergeant.org> XML::XPath module. See
Template::Plugin::XML::XPath and XML::XPath for further
details.

[% USE xpath = XML.XPath(xmlfile) %]
[% FOREACH page = xpath.findnodes('/html/body/page')

%]
[% page.getAttribute('title') %]

[% END %]; The plugin requires the XML::XPath module, available from
CPAN:

http://www.cpan.org/modules/by-module/XML/

BUGS / ISSUES

� It might be worthwhile being able to distinguish: between absolute module names and those which should
be applied relative to PLUGIN_BASE directories. For
example, use 'MyNamespace::MyModule' to denote abso
lute module names (e.g. LOAD_PERL), and 'MyNames
pace.MyModule' to denote relative to PLUGIN_BASE.

AUTHOR

Andy Wardley <abw@andywardley.com>

<http://www.andywardley.com/|http://www.andywardley.com/>

VERSION

2.57, distributed as part of the Template Toolkit version
2.08, released on 30 July 2002.

COPYRIGHT

Ltd.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

docs.sk

comprehensive documentation repository

In section