NAME¶
Config::Model::Iterator - Iterates forward or backward a configuration tree
VERSION¶
version 2.061
SYNOPSIS¶
use Config::Model;
use Log::Log4perl qw(:easy);
Log::Log4perl->easy_init($WARN);
# define configuration tree object
my $model = Config::Model->new;
$model->create_config_class(
name => "Foo",
element => [
[qw/bar baz/] => {
type => 'leaf',
value_type => 'string',
level => 'important' ,
},
]
);
$model->create_config_class(
name => "MyClass",
element => [
foo_nodes => {
type => 'hash', # hash id
index_type => 'string',
level => 'important' ,
cargo => {
type => 'node',
config_class_name => 'Foo'
},
},
],
);
my $inst = $model->instance( root_class_name => 'MyClass' );
# create some Foo objects
$inst->config_root->load("foo_nodes:foo1 - foo_nodes:foo2 ") ;
my $my_leaf_cb = sub {
my ($iter, $data_r,$node,$element,$index, $leaf_object) = @_ ;
print "leaf_cb called for ",$leaf_object->location,"\n" ;
} ;
my $my_hash_cb = sub {
my ($iter, $data_r,$node,$element,@keys) = @_ ;
print "hash_element_cb called for element $element with keys @keys\n" ;
} ;
my $iterator = $inst -> iterator (
leaf_cb => $my_leaf_cb,
hash_element_cb => $my_hash_cb ,
);
$iterator->start ;
### prints
# hash_element_cb called for element foo_nodes with keys foo1 foo2
# leaf_cb called for foo_nodes:foo1 bar
# leaf_cb called for foo_nodes:foo1 baz
# leaf_cb called for foo_nodes:foo2 bar
# leaf_cb called for foo_nodes:foo2 baz
DESCRIPTION¶
This module provides a class that is able to iterate forward or backward a
configuration tree. The iterator will stop and call back user defined
subroutines on one of the following condition:
- •
- A configuration item contains an error (mostly undefined mandatory
values)
- •
- A configuration item contains warnings and the constructor's argument
"call_back_on_warning" was set.
- •
- A configuration item has a "important" level and the
constructor's argument "call_back_on_important" was set.. See
level parameter for details.
The iterator supports going forward and backward (to support "back"
and "next" buttons on a wizard widget).
CONSTRUCTOR¶
The constructor should be used only by Config::Model::Instance with the iterator
method.
Creating an iterator¶
A iterator requires at least two kind of call-back: a call-back for leaf
elements and a call-back for hash elements (which will be also used for list
elements).
These call-back must be passed when creating the iterator (the parameters are
named "leaf_cb" and "hash_element_cb")
Here are the the parameters accepted by "iterator":
call_back_on_important¶
Whether to call back when an important element is found (default 0).
call_back_on_warning¶
Whether to call back when an item with warnings is found (default 0).
status¶
Specifies the status of the element scanned by the wizard (default 'standard').
leaf_cb¶
Subroutine called backed for leaf elements. See "Callback prototypes"
in Config::Model::ObjTreeScanner for signature and details. (mandatory)
hash_element_cb¶
Subroutine called backed for hash elements. See "Callback prototypes"
in Config::Model::ObjTreeScanner for signature and details. (mandatory)
Custom callbacks¶
By default, "leaf_cb" will be called for all types of leaf elements
(i.e enum. integer, strings, ...). But you can provide dedicated call-back for
each type of leaf:
enum_value_cb, integer_value_cb, number_value_cb, boolean_value_cb,
uniline_value_cb, string_value_cb
Likewise, you can also provide a call-back dedicated to list elements with
"list_element_cb"
Methods¶
start¶
Start the scan and perform call-back when needed. This function will return when
the scan is completely done.
bail_out¶
When called, a variable is set so that all call_backs will return as soon as
possible. Used to abort wizard.
go_forward¶
Set wizard in forward (default) mode.
go_backward¶
Set wizard in backward mode.
AUTHOR¶
Dominique Dumont, (ddumont at cpan dot org)
SEE ALSO¶
Config::Model, Config::Model::Instance, Config::Model::Node,
Config::Model::HashId, Config::Model::ListId, Config::Model::Value,
Config::Model::CheckList, Config::Model::ObjTreeScanner,
AUTHOR¶
Dominique Dumont
COPYRIGHT AND LICENSE¶
This software is Copyright (c) 2014 by Dominique Dumont.
This is free software, licensed under:
The GNU Lesser General Public License, Version 2.1, February 1999