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NAME

DBIx::Custom::Mapper - Mapper of parameter

SYNOPSYS

  my $mapper = $dbi->mapper(param => $param);
  my $new_param = $mapper->map(
    title => 'book.title', # Key
    author => sub { '%' . $_[0] . '%'} # Value
    price => ['book.price' => sub { '%' . $_[0] . '%' }], # Key and value
  );

ATTRIBUTES

param

  my $param = $mapper->param;
  $mapper = $mapper->param({title => 'Perl', author => 'Ken'});

Parameter.

pass

  my $pass = $mapper->pass;
  $mapper = $mapper->pass([qw/title author/]);

the key and value is copied without change when map method is executed.

condition

  my $condition = $mapper->condition;
  $mapper = $mapper->condition('exists');

Mapping condtion, default to length.

You can set the following values to condition.

  • exists

      condition => 'exists'

    If key exists, key and value is mapped.

  • defined

      condition => 'defined';

    If value is defined, key and value is mapped.

  • length

      condition => 'length';

    If value is defined and has length, key and value is mapped.

  • code reference

      condition => sub { defined $_[0] }

    You can set code reference to condtion. The subroutine return true, key and value is mapped.

METHODS

DBIx::Custom::Mapper inherits all methods from Object::Simple and implements the following new ones.

map

  my $new_param = $mapper->map(
    price => {key => 'book.price'}
    title => {value => '%<value>%'}
    author => ['book.author' => '%<value>%']
  );

  my $new_param = $mapper->map(
    price => {key => 'book.price'}
    title => {value => sub { '%' . shift . '%'}}
    author => ['book.author' => sub { '%' . shift . '%'}]
  );

Map parameter in param attribute into new parameter.

For example, if param is set to

  {
    price => 1900,
    title => 'Perl',
    author => 'Ken',
    issue_date => '2010-11-11'
  }

The following hash reference is returned.

  {
    'book.price' => 1900,
    title => '%Perl%',
    'book.author' => '%Ken%',
  }

    Syntax:

    * String => Hash reference

      # String => Hash reference
      price => {key => 'book.price'}
      title => {value => '%<value>%'}
      title => {value => sub { '%' . shift . '%'}}

    If key is used, only key name is mapped to new parameter

      # Rule
      price => {key => 'book.price'}
      # Parameter
      price => 1900,
      # New parameter
      'book.price' => 1900,

    If value is used, only value is mapped to new parameter

      # Rule
      title => {value => '%<value>%'}
      title => {value => sub { '%' . shift . '%'}}
      
      # Parameter
      title => 'Perl',
      # New parameter
      title => '%Perl%',

    <value>> is replaced by original value. You can use code reference to convert original value.

    * String => Array reference

      # String => Array reference
      author => ['book.author' => '%<value>%']

    Both key name name and value is mapped to new parameter. This is same as the following syntax.

      # Rule
      {key => 'book.author', value => '%<value>%'}

By default, If the value has length, key and value is mapped.

  title => 'Perl'  # Mapped
  {title => '' }   # Not mapped
  {title => undef} # Not mapped
  {}               # Not mapped

You can set change mapping condition by condition attribute.

  $mapper->condition('defined');

Or you can set condtion option for each key.

  my $new_param = $mapper->map(
    price => {key => 'book.price', condition => 'defined'}]
    title => {value => sub { '%' . $_[0] . '%'}, condition => 'defined'}
    author => ['book.author', sub { '%' . $_[0] . '%'}, 'exists']
  );

If pass attribute is set, the keys and value is copied without change.

  $mapper->pass([qw/title author/]);
  my $new_param = $mapper->map(price => {key => 'book.price'});

The following hash reference

  {title => 'Perl', author => 'Ken', price => 1900}

is mapped to

  {title => 'Perl', author => 'Ken', 'book.price' => 1900}

2 POD Errors

The following errors were encountered while parsing the POD:

Around line 201:

You forgot a '=back' before '=head1'

Around line 239:

You can't have =items (as at line 243) unless the first thing after the =over is an =item