NAME
Config::TT2 - Reading configuration files with the Template-Toolkit
parser.
ABSTRACT
Define configuration files in the powerful, flexible and extensible
Template-Toolkit syntax.
SYNOPSIS
use Config::TT2;
my $ctt2 = Config::TT2->new;
my $cfg_stash = $ctt2->process($file);
DESCRIPTION
"Config::TT2" extends the "Template-Toolkit" aka "TT2" in a very special
way:
It returns the VARIABLES STASH instead of the template text!
The TT2 syntax is very powerful, flexible and extensible. One of the key
features of TT2 is the ability to bind template variables to any kind of
Perl data: scalars, lists, hash arrays, sub-routines and objects.
See Template::Manual::Variables for a reference.
E.g. this Template-Toolkit config
[% # tt2 directive start-tag
scalar = 'string' # strings in single or double quotes
array = [ 10 20 30 ] # commas are optional
rev = array.reverse # powerful virtual methods
item = array.0 # interpolate previous value
hash = { foo = 'bar' # hashes to any depth
moo = array # points to above arrayref
}
%] # tt2 directive end-tag
is returned as a perl datastructure:
'scalar' => 'string'
'array' => ARRAY(0x8ad2708)
0 10
1 20
2 30
'rev' => ARRAY(0x8afe740)
0 30
1 20
2 10
'item' => 10
'hash' => HASH(0x8afe160)
'foo' => 'bar'
'moo' => ARRAY(0x8ad2708)
-> REUSED_ADDRESS
METHODS
new(%config)
The "new()" constructor method instantiates a new "Config::TT2" object.
This method croaks on error.
Configuration items may be passed as a list of items or a hash array:
my $ctt2 = Config::TT2->new(
ABSOLUTE => 0,
DEBUG => 'all',
);
The supported configuration options are the same as for "Template",
please see the Template::Manual::Config as a reference and the
LIMITATIONS section below.
The preset default options which differ from the Template default
options are:
STRICT = 1 # undefined vars or values cause exceptions
ABSOLUTE = 1 # files with absolute filenames allowed
RELATIVE = 1 # files with relative filenames allowed
CACHE_SIZE = 0 # don't cache compiled config files
process($config, $variables)
The "process()" method is called to process a config file or string. The
first parameter indicates the input as one of: a filename; a reference
to a text string containing the config text; or a file handle reference,
from which the config can be read.
A reference to a hash array may be passed as the second parameter,
containing definitions of input variables.
$stash = $ctt2->process( '.app.cfg', {foo => $ENV{APP_FOO}} );
The returned datastructure is a "Template::Stash" object. You may access
the key and values through normal perl dereferencing:
$item = $stash->{hash}{moo}[0];
or via the "Template::Stash->get" method like:
$item = $stash->get('hash.moo.0');
For debugging purposes you can even request the template output from the
process method:
($stash, $output) = $ctt2->process( $config );
The method croaks on error.
LIMITATIONS
The Template-Toolkit processor uses the toplevel variables "template"
und "component" for meta information during template file processing.
You MUST NOT define or redefine these toplevel variables at object
creation, processing or within the config files.
See the section "Special Variables" in Template::Manual::Variables.
The "process" method purges these toplevel variables unconditionally
after processing but before returning the stash.
See also the special meaning of the "global" toplevel variable.
Successive calls to "process" with the same Config::TT2 instance MUST be
avoided. The Template CONTEXT and STASH have states belonging to the
processed config text. Create new instances for successive "process"
calls.
$stash1 = Config::TT2->new->process($file1);
$stash2 = Config::TT2->new->process($file2);
The following Template options are not supported with Config::TT2:
PRE_PROCESS
PROCESS
POST_PROCESS
WRAPPER
AUTO_RESET
DEFAULT
OUTPUT
OUTPUT_PATH
ERROR
ERRORS
EXTENSIONS AND VIRTUAL METHODS
With the "context" method you can get/set the underlying
Template::Context object.
context()
Getter/setter method for the underlying Template::Context object.
With the context you can also access the stash and define new virtual
methods BEFORE processing.
$ctt2 = Config::TT2->new;
$ctt2->context->stash->define_vmethod( $type, $name, $code_ref );
$cfg_stash = $ctt2->process($cfg_file);
See the manuals Template::Stash, Template::Context and
Template::Manual::Internals.
SEE ALSO
Config::Any::TT2, the corresponding Config::Any plugin.
Template::Manual::Intro, Template::Manual::Syntax,
Template::Manual::Config, Template::Manual::Variables,
Template::Manual::VMethods
AUTHOR
Karl Gaissmaier, "<gaissmai at cpan.org>"
BUGS
Please report any bugs or feature requests to "bug-config-tt at
rt.cpan.org", or through the web interface at
<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Config-TT2>. I will be
notified, and then you'll automatically be notified of progress on your
bug as I make changes.
SUPPORT
You can find documentation for this module with the perldoc command.
perldoc Config::TT2
You can also look for information at:
* RT: CPAN's request tracker (report bugs here)
<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Config-TT2>
* AnnoCPAN: Annotated CPAN documentation
<http://annocpan.org/dist/Config-TT2>
* CPAN Ratings
<http://cpanratings.perl.org/d/Config-TT2>
* Search CPAN
<http://search.cpan.org/dist/Config-TT2/>
LICENSE AND COPYRIGHT
Copyright 2012 Karl Gaissmaier.
This program is free software; you can redistribute it and/or modify it
under the terms of either: the GNU General Public License as published
by the Free Software Foundation; or the Artistic License.
See http://dev.perl.org/licenses/ for more information.