Config::Model::AnyId(3pm)

NAME
Config::Model::AnyId - Base class for hash or list element

SYNOPSIS
 $model ->create_config_class
  (
   ...
   element
   => [
       bounded_hash
       => { type => 'hash',                 # hash id
            index_type  => 'integer',

            # hash boundaries
            min_index => 1, max_index => 123, max_nb => 2 ,

            # specify cargo held by hash
            cargo => { type => 'leaf',
                       value_type => 'string'
                     },
          },
      bounded_list
       => { type => 'list',                 # list id

            max_index => 123,
            cargo => { type => 'leaf',
                       value_type => 'string'
                     },
          },
      hash_of_nodes
      => { type => 'hash',                 # hash id
           index_type  => 'integer',
           cargo => { type => 'node',
                      config_class_name => 'Foo'
                    },
         },
      ]
  ) ;

DESCRIPTION
This class provides hash or list elements for a Config::Model::Node.

The hash index can either be en enumerated type, a boolean, an integer or a string.

CONSTRUCTOR
AnyId object should not be created directly.

Hash or list model declaration
A hash or list element must be declared with the following parameters:

type
    Mandatory element type. Must be "hash" or "list" to have a collection element. The actual element type must be specified by "cargo =" type> (See "CAVEATS").

index_type
    Either "integer" or "string". Mandatory for hash.

ordered
    Whether to keep the order of the hash keys (default no). (a bit like Tie::IxHash). The hash keys are ordered along their creation. The order can be modified with swap, move_up or move_down.

cargo
    Hash ref specifying the cargo held by the hash of list. This has must contain:

    type
        Can be "node" or "leaf" (default).

    config_class_name
        Specifies the type of configuration object held in the hash. Only valid when "cargo" "type" is "node".

    <other>
        Constructor arguments passed to the cargo object. See Config::Model::Node when "cargo->type" is "node". See Config::Model::Value when "cargo->type" is "leaf".

min_index
    Specify the minimum value (optional, only for hash and for integer index)

max_index
    Specify the maximum value (optional, only for integer index)

max_nb
    Specify the maximum number of indexes. (hash only, optional, may also be used with string index type)

default_keys
    When set, the default parameter (or set of parameters) are used as default keys hashes and created automatically when the keys or exists functions are used on an empty hash.

    You can use "default_keys => 'foo'", or "default_keys => ['foo', 'bar']".

default_with_init
    To perform special set-up on children nodes you can also use

       default_with_init =>  { 'foo' => 'X=Av Y=Bv'  ,
                               'bar' => 'Y=Av Z=Cv' }

follow_keys_from
    Specifies that the keys of the hash follow the keys of another hash in the configuration tree. In other words, the hash you're creating will always have the same keys as the other hash.

       follow_keys_from => '- another_hash'

allow_keys
    Specifies authorized keys:

      allow_keys => ['foo','bar','baz']

allow_keys_from
    A bit like the "follow_keys_from" parameters. Except that the hash pointed to by "allow_keys_from" specified the authorized keys for this hash.

      allow_keys_from => '- another_hash'

allow_keys_matching
    Keys must match the specified regular expression. For instance:

      allow_keys_matching => '^foo\d\d$'

auto_create_keys
    When set, the default parameter (or set of parameters) are used as keys hashes and created automatically. (valid only for hash elements)

    Called with "auto_create => 'foo'", or "auto_create => ['foo', 'bar']".

warn_if_key_match
    Issue a warning if the key matches the specified regular expression

warn_unless_key_match
    Issue a warning unless the key matches the specified regular expression

auto_create_ids
    Specifies the number of elements to create automatically. E.g. "auto_create => 4" will initialize the list with 4 undef elements. (valid only for list elements)

warp
    See "Warp: dynamic value configuration" below.

Warp: dynamic value configuration
The Warp functionality enables an HashId or ListId object to change its default settings (e.g. "min_index", "max_index" or "max_nb" parameters) dynamically according to the value of another "Value" object. (See Config::Model::WarpedThing for explanation on warp mechanism)

For instance, with this model:

 $model ->create_config_class
  (
   name => 'Root',
   'element'
   => [
       macro => { type => 'leaf',
                  value_type => 'enum',
                  name       => 'macro',
                  choice     => [qw/A B C/],
                },
       warped_hash => { type => 'hash',
                        index_type => 'integer',
                        max_nb     => 3,
                        warp       => {
                                       follow => '- macro',
                                       rules => { A => { max_nb => 1 },
                                                  B => { max_nb => 2 }
                                                }
                                      },
                        cargo => { type => 'node',
                                   config_class_name => 'Dummy'
                                 }
                      },
     ]
  );

Setting "macro" to "A" will mean that "warped_hash" can only accept one instance of "Dummy".

Setting "macro" to "B" will mean that "warped_hash" will accept two instances of "Dummy".

Like other warped class, a HashId or ListId can have multiple warp masters (See "Warp follow argument" in Config::Model::WarpedThing:

  warp => { follow => { m1 => '- macro1',
                        m2 => '- macro2'
                      },
            rules  => [ '$m1 eq "A" and $m2 eq "A2"' => { max_nb => 1},
                        '$m1 eq "A" and $m2 eq "B2"' => { max_nb => 2}
                      ],
          }

  Warp and auto_create_ids or auto_create_keys
When a warp is applied with "auto_create_keys" or "auto_create_ids" parameter, the auto_created items are created if they are not already present. But this warp will never remove items that were previously auto created.

For instance, if a tied hash is created with "auto_create => [a,b,c]", the hash contains "(a,b,c)".

Then if a warp is applied with "auto_create => [c,d,e]", the hash will contain "(a,b,c,d,e)". The items created by the first auto_create are not removed.

  Warp and max_nb
When a warp is applied, the items that do not fit the constraint (e.g. min_index, max_index) are removed.

For the max_nb constraint, an exception will be raised if a warp leads to a nb of items greater than the max_nb constraint.

Introspection methods
The following methods returns the current value stored in the Id object (as declared in the model unless they were warped):

min_index
max_index
max_nb
index_type
default_keys
default_with_init
follow_keys_from
auto_create_ids
auto_create_keys
ordered
morph
config_model

  get_cargo_type()
Returns the object type contained by the hash or list (i.e. returns "cargo -> type").

  get_cargo_info( < what > )
Returns more info on the cargo contained by the hash or list. "what" may be "value_type" or any other cargo info stored in the model. Will return undef if the requested info was not provided in the model.

  get_default_keys
Returns a list (or a list ref) of the current default keys. These keys can be set by the "default_keys" or "default_with_init" parameters or by the other hash pointed by "follow_keys_from" parameter.

  name()
Returns the object name. The name finishes with ' id'.

  config_class_name()
Returns the config_class_name of collected elements. Valid only for collection of nodes.

This method will return undef if "cargo" "type" is not "node".

Informations management

  fetch_with_id ( index => $idx , [ check => 'no' ])
Fetch the collected element held by the hash or list. Index check is 'yes' by default. Can be called with one parameter: idx.

  get( path, [ custom | preset | standard | default ])
Get a value from a directory like path.

  set( path, value )
Set a value with a directory like path.

  copy ( from_index, to_index )
Deep copy an element within the hash or list. If the element contained by the hash or list is a node, all configuration information is copied from one node to another.

  fetch_all()
Returns an array containing all elements held by the hash or list.

  fetch_all_values( mode => ..., check => ...)
Returns an array containing all defined values held by the hash or list. (undefined values are simply discarded)

With "mode" parameter, this method will return either:

custom
    The value entered by the user

preset
    The value entered in preset mode

standard
    The value entered in preset mode or checked by default.

default
    The default value (defined by the configuration model)

  get_all_indexes()
Returns an array containing all indexes of the hash or list. Hash keys are sorted alphabetically, except for ordered hashed.

  defined ( index )
Returns true if the value held at "index" is defined.

  exists ( index )
Returns true if the value held at "index" exists (i.e the key exists but the value may be undefined). This method may not make sense for list element.

  delete ( index )
Delete the "index"ed value

  clear()
Delete all values (also delete underlying value or node objects).

  clear_values()
Delete all values (without deleting underlying value objects).

  warning_msg ( [index] )
Returns warnings concerning indexes of this hash. Without parameter, returns a hash ref or undef. With an index, return the warnings concerning this index or undef.

AUTHOR
Dominique Dumont, ddumont [AT] cpan [DOT] org

SEE ALSO
Config::Model, Config::Model::Instance, Config::Model::Node, Config::Model::WarpedNode, Config::Model::HashId, Config::Model::ListId, Config::Model::CheckList, Config::Model::Value