Config::Model::WarpedNode man page on Pidora

Man page or keyword search:  
man Server   31170 pages
apropos Keyword Search (all sections)
Output format
Pidora logo
[printable version]

Config::Model::WarpedNUser3Contributed Perl DocumeConfig::Model::WarpedNode(3)

NAME
       Config::Model::WarpedNode - Node that change config class properties

VERSION
       version 1.235

SYNOPSIS
	use Config::Model;
	use Log::Log4perl qw(:easy);
	Log::Log4perl->easy_init($WARN);

	my $model = Config::Model->new;
	foreach (qw/X Y/) {
	   $model->create_config_class(
	       name    => "Class$_",
	       element => [ foo => {qw/type leaf value_type string/} ]
	   );
	}
	$model->create_config_class(
	   name => "MyClass",

	   element => [
	       master_switch => {
		   type	      => 'leaf',
		   value_type => 'enum',
		   choice     => [qw/cX cY/]
	       },

	       'a_warped_node' => {
		   type	  => 'warped_node',
		   follow => { ms => '! master_switch' },
		   rules  => [
		       '$ms eq "cX"' => { config_class_name => 'ClassX' },
		       '$ms eq "cY"' => { config_class_name => 'ClassY' },
		   ]
	       },

	   ],
	);

	my $inst = $model->instance(root_class_name => 'MyClass' );
	my $root = $inst->config_root ;

	print "Visible elements: ",join(' ',$root->get_element_name),"\n" ;
	# Visible elements: master_switch

	$root->load( step => 'master_switch=cX' );
	print "Visible elements: ",join(' ',$root->get_element_name),"\n" ;
	# Visible elements: master_switch a_warped_node

	my $node = $root->grab('a_warped_node') ;
	print "a_warped_node class: ",$node->config_class_name,"\n" ;
	# a_warped_node class: ClassX

	$root->load( step => 'master_switch=cY' );
	print "a_warped_node class: ",$node->config_class_name,"\n" ;
	# a_warped_node class: ClassY

DESCRIPTION
       This class provides a way to change dynamically the configuration class
       (or some other properties) of a node. The changes are done according to
       the model declaration.

       This declaration will specify one (or several) leaf in the
       configuration tree that will trigger the actual property change of the
       warped node. This leaf is also referred as warp master.

       When the warp master(s) value(s) changes, "WarpedNode" will create an
       instance of the new class required by the warp master.

       If the morph parameter is set, the values held by the old object are
       (if possible) copied to the new instance of the object using copy_from
       method.

       Warped node can alter the following properties:

	config_class_name
	experience
	level

Constructor
       "WarpedNode" should not be created directly.

Warped node model declaration
   Parameter overview
       A warped node must be declared with the following parameters:

       type
	   Always set to "warped_node".

       follow
	   Grab string leading to the "Config::Model::Value" warp master.  See
	   "Warp follow argument" in Config::Model::WarpedThing for details.

       morph
	   boolean. If 1, "WarpedNode" will try to recursively copy the value
	   from the old object to the new object using copy_from method.  When
	   a copy is not possible, undef values will be assigned to object
	   elements.

       rules
	   Hash or array ref that specify the property change rules according
	   to the warp master(s) value(s).  See "Warp rules argument" in
	   Config::Model::WarpedThing for details on how to specify the warp
	   master values (or combination of values).

   Effect declaration
       For a warped node, the effects are declared with these parameters:

       config_class_name
	       When requested by the warp master,the "WarpedNode" will create
	       a new object of the type specified by this parameter:

		 XZ => { config_class_name => 'SlaveZ' }

	       If you pass an array ref, the array will contain the class name
	       and constructor arguments :

		 XY  => { config_class_name => ['SlaveY', foo => 'bar' ], },

       experience
	       Switch the experience of the slot when the object is warped in.

Forwarded methods
       The following methods are forwarded to contained node:

       fetch_element config_class_name get_element_name has_element
       is_element_available element_type load fetch_element_value get_type
       get_cargo_type describe config_model

Methods
   name
       Return the name of the node (even if warped out).

   is_accessible
       Returns true if the node hidden behind this warped node is accessible,
       i.e. the warp master have values so a node was warped in.

   get_actual_node
       Returns the node object hidden behind the warped node. Croaks if the
       node is not accessible.

   load_data ( hash_ref )
       Load configuration data with a hash ref. The hash ref key must match
       the available elements of the node carried by the warped node.

EXAMPLE
	$model ->create_config_class
	 (
	  experience => [ bar => 'advanced'] ,
	  element =>
	   [
	    tree_macro => { type => 'leaf',
			    value_type => 'enum',
			    choice     => [qw/XX XY XZ ZZ/]
			  },
	    bar =>  {
		      type => 'warped_node',
		      follow => '! tree_macro',
		      morph => 1,
		      rules => [
				XX => { config_class_name
					  => [ 'ClassX', 'foo' ,'bar' ]}
				XY => { config_class_name => 'ClassY'},
				XZ => { config_class_name => 'ClassZ'}
			       ]
		    }
	   ]
	 );

       In the example above we see that:

       ·   The 'bar' slot can refer to a "ClassX", "ClassZ" or "ClassY"
	   object.

       ·   The warper object is the "tree_macro" attribute of the root of the
	   object tree.

       ·   When "tree_macro" is set to "ZZ", "bar" will not be available.
	   Trying to access bar will raise an exception.

       ·   When "tree_macro" is changed from "ZZ" to "XX", "bar" will refer to
	   a brand new "ClassX" object constructed with "ClassX->new(foo =>
	   'bar')"

       ·   Then, if "tree_macro" is changed from "XX" to "XY", "bar" will
	   refer to a brand new "ClassY" object. But in this case, the object
	   will be initialized with most if not all the attributes of
	   "ClassX". This copy will be done whenever "tree_macro" is changed.

AUTHOR
       Dominique Dumont, (ddumont at cpan dot org)

SEE ALSO
       Config::Model::Instance, Config::Model, Config::Model::HashId,
       Config::Model::ListId, Config::Model::AnyThing,
       Config::Model::WarpedThing, Config::Model::WarpedNode,
       Config::Model::Value

perl v5.14.1			  2011-07-22	  Config::Model::WarpedNode(3)
[top]

List of man pages available for Pidora

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net