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Config::Model::Backend::IniFile

Read and write config as a INI file

version 2.082

 use Config::Model;
 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

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'.

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.

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

Optional parameters declared in the model:

Change the character that starts comments in the INI file. Default is '"#"'.
See "Arbitrary class name"
Is a kind of exception of the above rule. See also "Arbitrary class name"
Boolean. When set, sections names are converted to lowercase.
Idem for key name
Idem for all values.
Some INI values are in fact a list of items separated by a space or a comma. This parameter specifies the regex to use to split the value into a list. This applies only to "list" elements.
Conversely, the list element split with "split_list_value" needs to be written back with a string to join them. Specify this string (usually ' ' or ', ') with "join_list_value".
Some INI values are in fact a check list of items separated by a space or a comma. This parameter specifies the regex to use to split the value read from the file into a list of items to check. This applies only to "check_list" elements.
Conversely, the check_list element split with "split_list_value" needs to be written back with a string to join them. Specify this string (usually ' ' or ', ') with "join_check_list_value".
Array ref. Reserved for boolean value. Specify how to write a boolean value. Default is "[0,1]" which may not be the most readable. "write_boolean_as" can be specified as "['false','true']" or "['no','yes']".

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.

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

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',
        }
    ],

Of course they are exceptions. For instance, in "Multistrap", the "[General]" INI class must be mapped to a specific node object. This can be specified with the "section_map" parameter:

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

"section_map" can also map an INI class to the root node:

    read_config => [
        {
            backend => 'ini_file',
            store_class_in_hash => 'sections',
            section_map => {
                General => '!'
            },
        }
    ],

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.

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.

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

Config::Model, Config::Model::BackendMgr, Config::Model::Backend::Any,

Dominique Dumont

This software is Copyright (c) 2005-2016 by Dominique Dumont.

This is free software, licensed under:

  The GNU Lesser General Public License, Version 2.1, February 1999