NAME

       Config::Model::Backend::Yaml - Read and write config as a YAML data structure

VERSION

       version 2.134

SYNOPSIS

        use Config::Model ;
        use Data::Dumper ;

        # define configuration tree object
        my $model = Config::Model->new ;
        $model ->create_config_class (
           name => "MyClass",
           element => [
               [qw/foo bar/] => {
                   type => 'leaf',
                   value_type => 'string'
               },
               baz => {
                   type => 'hash',
                   index_type => 'string' ,
                   cargo => {
                       type => 'leaf',
                       value_type => 'string',
                   },
               },
           ],
         rw_config  => {
           backend => 'yaml',
           config_dir => '/tmp',
           file  => 'foo.yml',
           auto_create => 1,
         }
        ) ;

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

        my $root = $inst->config_root ;

        my $steps = 'foo=yada bar="bla bla" baz:en=hello
                    baz:fr=bonjour baz:hr="dobar dan"';
        $root->load( steps => $steps ) ;
        $inst->write_back ;

       Now, "/tmp/foo.yml" contains:

        ---
        bar: bla bla
        baz:
          en: hello
          fr: bonjour
          hr: dobar dan
        foo: yada

DESCRIPTION

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

       Note:

       •   Undefined values are skipped for list element. I.e. if a list element contains "('a',undef,'b')", the
           data structure contains 'a','b'.

       •   YAML file is not created (and may be deleted) when no data is to be written.

   Class with only one hash element
       If  the  root  node contains a single hash or list element, only the content of this hash is written in a
       YAML file.

       For example, if a class contains:

             element => [
               baz => {
                   type => 'hash',
                   index_type => 'string' ,
                   cargo => {
                       type => 'leaf',
                       value_type => 'string',
                   },
               },

       If the configuration is loaded with:

        $root->load("baz:one=un baz:two=deux")

       Then the written YAML file does not show "baz":

        ---
        one: un
        two: deux

       Likewise, a YAML file for a class with a single list "baz" element would be written with:

        ---
        - un
        - deux

YAML class

       As of v2.129, this backend uses YAML::XS 0.69 or later.

       For security reason, loading a Perl blessed object is disabled.

       Value of type boolean are written as boolean values in YAML files.

backend parameter

   yaml_class
       This parameter is ignored as of version 2.129.

CONSTRUCTOR

   new
       Parameters: "( node => $node_obj, name => 'yaml' )"

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

   read
       Read YAML file and load into $node_obj tree.

       When a file is read, "read" returns 1.

   write
       Write YAML File using $node_obj data.

       "write" returns 1.

AUTHOR

       Dominique Dumont, (ddumont at cpan dot org)

SEE ALSO

       Config::Model, Config::Model::BackendMgr, Config::Model::Backend::Any, YAML::XS

AUTHOR

       Dominique Dumont

COPYRIGHT AND LICENSE

       This software is Copyright (c) 2018 by Dominique Dumont.

       This is free software, licensed under:

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

SUPPORT

   Websites
       The following websites have more information about this module, and may be of help to you. As always,  in
       addition to those websites please use your favorite search engine to discover more resources.

       •   CPANTS

           The CPANTS is a website that analyzes the Kwalitee ( code metrics ) of a distribution.

           <http://cpants.cpanauthors.org/dist/Config-Model-Backend-Yaml>

       •   CPAN Testers

           The  CPAN  Testers  is  a  network  of  smoke  testers  who  run  automated  tests  on  uploaded CPAN
           distributions.

           <http://www.cpantesters.org/distro/C/Config-Model-Backend-Yaml>

       •   CPAN Testers Matrix

           The CPAN Testers Matrix is a website that provides a visual  overview  of  the  test  results  for  a
           distribution on various Perls/platforms.

           <http://matrix.cpantesters.org/?dist=Config-Model-Backend-Yaml>

       •   CPAN Testers Dependencies

           The CPAN Testers Dependencies is a website that shows a chart of the test results of all dependencies
           for a distribution.

           <http://deps.cpantesters.org/?module=Config::Model::Backend::Yaml>

   Bugs / Feature Requests
       Please  report  any  bugs  or  feature  requests  by  email  to "ddumont at cpan.org", or through the web
       interface at <https://github.com/dod38fr/config-model-backend-yaml/issues>.  You  will  be  automatically
       notified of any progress on the request by the system.

   Source Code
       The  code  is open to the world, and available for you to hack on. Please feel free to browse it and play
       with it, or whatever. If you want to contribute patches, please send me a diff or prod me  to  pull  from
       your repository :)

       <http://github.com/dod38fr/config-model-backend-yaml>

         git clone git://github.com/dod38fr/config-model-backend-yaml.git

perl v5.36.0                                       2022-10-14                  Config::Model::Backend::Yaml(3pm)