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Dominique Dumont
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Config::Model::Instance - Instance of configuration tree


version 1.213


 my $model = Config::Model->new() ;
 $model ->create_config_class ( ... ) ;

 my $inst = $model->instance (root_class_name => 'SomeRootClass', 
                              instance_name    => 'some_name');


This module provides an object that holds a configuration tree.


An instance object is created by calling instance method on an existing model:

 my $inst = $model->instance (root_class_name => 'SomeRootClass', 
                              instance_name => 'test1');

The directory (or directories) holding configuration files is specified within the configuration model. For test purpose you can change the "root" directory with root_dir parameter:


Pseudo root directory where to read and write configuration files


Specify which backend to use. See "write_back ( ... )" for details


When set, configuration files will not be read when creating configuration tree.

Note that the root directory specified within the configuration model will be overridden by root_dir parameter.

If you need to load configuration data that are not correct, you can use force_load => 1. Then, wrong data will be discarded.



Returns the instance name.


Returns the root object of the configuration tree.


Destroy current configuration tree (with data) and returns a new tree with data (and annotations) loaded from disk.


Returns the model (Config::Model object) of the configuration tree.


Returns the object loading and saving annotations. See Config::Model::Annotation for details.

preset_start ()

All values stored in preset mode are shown to the user as default values. This feature is useful to enter configuration data entered by an automatic process (like hardware scan)

preset_stop ()

Stop preset mode

preset ()

Get preset mode

data( kind, [data] )

The data method provide a way to store some arbitrary data in the instance object.

load( "..." )

Load configuration tree with configuration data. See Config::Model::Loader for more details

searcher ( )

Returns an object dedicated to search an element in the configuration model (respecting privilege level).

This method returns a Config::Model::Searcher object. See Config::Model::Searcher for details on how to handle a search.

wizard_helper ( ... )

This method returns a Config::Model::WizardHelper object. See Config::Model::WizardHelper for details on how to create a wizard widget with this object.

wizard_helper arguments are explained in Config::Model::WizardHelper constructor arguments.

Auto read and write feature

Usually, a program based on config model must first create the configuration model, then load all configuration data.

This feature enables you to declare with the model a way to load configuration data (and to write it back). See Config::Model::AutoRead for details.


Returns root directory where configuration data is read from.


Get the preferred backend method for this instance (as passed to the constructor).


Returns root directory where configuration data is written to.

register_write_back ( backend_name, sub_ref )

Register a sub ref (with the backend name) that will be called with write_back method.

write_back ( ... )

Try to run all subroutines registered with register_write_back to write the configuration information until one succeeds (returns true). (See Config::Model::AutoRead for details).

You can specify here a pseudo root dir or another config dir to write configuration data back with root and config_dir parameters. This will override the model specifications.

You can force to use a backend by specifying backend => xxx. For instance, backend => 'augeas' or backend => 'custom'.

You can force to use all backend to write the files by specifying backend => 'all'.

write_back will croak if no write call-back are known.


Dominique Dumont, (ddumont at cpan dot org)


Config::Model, Config::Model::Node, Config::Model::Loader, Config::Model::Searcher, Config::Model::Value,