NAME

Config::Model::Backend::IniFile - Read and write config as a INI file

VERSION

version 1.255

SYNOPSIS

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

 my $model = Config::Model->new;
 $model->create_config_class (
    name    => "IniClass",
    element => [ 
        [qw/foo bar/] => {
            type => 'list',
            cargo => {qw/type leaf value_type string/}
        } 
    ]
 );

 # model for free INI class name and constrained class parameters
 $model->create_config_class(
    name => "MyClass",

    element => [
        'ini_class' => {
            type   => 'hash',
            index_type => 'string',
            cargo => { 
                type => 'node',
                config_class_name => 'IniClass' 
                },
            },
    ],

   read_config  => [
        { 
            backend => 'IniFile',
            config_dir => '/tmp',
            file  => 'foo.conf',
            store_class_in_hash => 'ini_class',
            auto_create => 1,
        }
    ],
 );

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

 $root->load('ini_class:ONE foo=FOO1 bar=BAR1 - 
              ini_class:TWO foo=FOO2' );

 $inst->write_back ;

Now /tmp/foo.conf will contain:

 ## file written by Config::Model
 [ONE]
 foo=FOO1

 bar=BAR1

 [TWO]
 foo=FOO2

DESCRIPTION

This module is used directly by Config::Model to read or write the content of a configuration tree written with INI syntax in Config::Model configuration tree.

This INI file can have arbitrary comment delimiter. See the example in the SYNOPSIS that sets a semi-column as comment delimiter. By default the comment delimiter is '#' like in Shell or Perl.

Note that undefined values are skipped for list element. I.e. if a list element contains ('a',undef,'b'), the data structure will contain 'a','b'.

Comments

This backend tries to read and write comments from configuration file. The comments are stored as annotation within the configuration tree. Bear in mind that comments extraction is based on best estimation as to which parameter the comment may apply. Wrong estimations are possible.

CONSTRUCTOR

new ( node => $node_obj, name => 'inifile' ) ;

Inherited from Config::Model::Backend::Any. The constructor will be called by Config::Model::AutoRead.

Parameters

Optional parameters declared in the model:

comment_delimiter

Change the character that starts comments in the INI file. Default is '#'.

store_class_in_hash

See "Arbitrary class name"

Mapping between INI structure and model

INI file typically have the same structure with 2 different conventions. The class names can be imposed by the application or may be chosen by user.

Imposed class name

In this case, the class names must match what is expected by the application. The elements of each class can be different. For instance:

  foo = foo_v
  [ A ]
  bar = bar_v
  [ B ]
  baz = baz_v

In this case, class A and class B will not use the same configuration class.

The model will have this structure:

 Root class 
 |- leaf element foo
 |- node element A of class_A
 |  \- leaf element bar
 \- node element B of class_B
    \-  leaf element baz
    

Arbitrary class name

In this case, the class names can be chosen by the end user. Each class will have the same elements. For instance:

  foo = foo_v
  [ A ]
  bar = bar_v1
  [ B ]
  bar = bar_v2

In this case, class A and class B will not use the same configuration class. The model will have this structure:

 Root class 
 |- leaf foo
 \- hash element my_class_holder
    |- key A (value is node of class_A)
    |  \- element-bar
    \- key B (value is node of class_A)
       \- element-bar

In this case, the my_class_holder name is specified in read_config with store_class_in_hash parameter:

    read_config  => [
        { 
            backend => 'IniFile',
            config_dir => '/tmp',
            file  => 'foo.ini',
            store_class_in_hash => 'my_class_holder',
        }
    ],

Methods

read ( io_handle => ... )

Of all parameters passed to this read call-back, only io_handle is used. This parameter must be IO::File object already opened for read.

It can also be undef. In this case, read() will return 0.

When a file is read, read() will return 1.

write ( io_handle => ... )

Of all parameters passed to this write call-back, only io_handle is used. This parameter must be IO::File object already opened for write.

write() will return 1.

AUTHOR

Dominique Dumont, (ddumont at cpan dot org); Krzysztof Tyszecki, (krzysztof.tyszecki at gmail dot com)

SEE ALSO

Config::Model, Config::Model::AutoRead, Config::Model::Backend::Any,

cpanm Config::Model

perl -MCPAN -e shell
install Config::Model