Perl: Counting Elements in a Complex Data Structure

Question

I am new to complex data structures. I kind of understand the idea behind them, but it's hard for me to get the data. I found out the structure of my current child problem using Data :: Dumper ....

$VAR1 = {
      '4' => {
               'engine_coded' => 0,
               'name' => 'FILTER_1',
               'filter_actions' => {
                                     'X_Override_Queue_Level' => 'Value'
                                   },
               'filter_criteria' => [
                                      [
                                        'X_Charge',
                                        '=',
                                        'X_CHARGE_1'
                                      ]
                                    ]
             }
    };

What I need to do is make sure that given the filter name ("4" in this case "), that" name "matters, as well as" filter_actions "and" filter_criteria ".

Does anyone have an idea how to do this? Many thanks! Jeni

Answer 1

Let me break it into pieces ...

First create a function that checks the structure:

sub validate
{
    my ($data) = @_;

    # always return true for now
    return 1;
}

... , :

sub validate
{
    my ($data, $filter_name) = @_;

    # always return true for now
    return 1;
}

- , , ; , :

sub validate
{
    my ($data, $filter_name) = @_;

    return if not exists $data->{$filter_name};

    # otherwise, return true
    return 1;
}

, . - "" ( , , , , , - undef ), :

sub validate
{
    my ($data, $filter_name) = @_;

    return if not defined $data->{$filter_name};

    # otherwise, return true
    return 1;
}

, filter_name, , , , hashref:

sub validate
{
    my ($data, $filter_name) = @_;

    return if not defined $data->{$filter_name};

    return if ref $data->{$filter_name} ne 'HASH';

    # otherwise, return true
    return 1;
}

"filter_actions" "filter_criteria" :

sub validate
{
    my ($data, $filter_name) = @_;

    return if not defined $data->{$filter_name};

    return if ref $data->{$filter_name} ne 'HASH';

    return if not defined $data->{$filter_name}{filter_actions};
    return if not defined $data->{$filter_name}{filter_actions};

    # otherwise, return true
    return 1;
}

! perl perldoc perlreftoot, perldoc perlref perldoc perldsc.

Answer 2

filter_actions/etc, $var->{4}->{filter_actions}. perldsc perl.

Answer 3

. , . , ​​.

use List::Util qw<first>;

sub validate_filter { 
    my ( $filters_ref, $filter_name ) = @_;
    my $filter  = $filter_name ? $filters_ref->{$filter_name} : $filters_ref;
    return 1 unless 
        my $missing 
            = first { !!$filter->{ $_ } } 
              qw<name filter_actions filter_criteria>
       ;
    if ( $missing ) { 
        Carp::croak( '"Missing '$missing' in filter!" );
    }
}

, , , , , ,

validate_filter( $filters, 4 );

, :

validate_filter( $filters->{4} );

, , .

If you are after checking the structure, you can choose this route. Based on your data, I show an example of a validation failure if a given filter_criteria cluster does not have an "=" operator for every third slot.

Same:

use Carp       qw<croak>;
use List::Util qw<first>;
use Params::Util ();

sub _test { 
    return 1 if shift->( $_ );
    local $Carp::CarpLevel = $Carp::CarpLevel + 2;
    Carp::croak( shift );
}

my $validators 
    = { filter_actions => sub {
           croak 'filter_actions is not deinfed!' unless defined;
           _test( \&Params::Util::_HASH, 'filter_actions must be hash!' );
        }
      , filter_criters => sub {
            croak 'filter_criteria is not defined!' unless defined $crit;
            _test( \&Params::Util::_ARRAY, 'filter_criteria must be non-empty ARRAY!' );
            foreach ( @$crit ) { 
                _test( \&Params::Util::_ARRAY, 'criteria must be non-empty ARRAYs' );
                _test( sub { 
                           my $arr = shift;
                           return if @$arr % 3;
                           # return whether any slot in sequence is not '='
                           return !first { $arr->[$_] ne '=' } 
                                   # every 3 beginning at 1
                                   grep  { $_ % 3 == 1 } (1..$#$arr)
                                   ;
                       }
                     , 'criteria must be key-value pairs separated by equal sign!' 
                     );
            }
        }
    };

And this will change the sub validate_filterlike so:

sub validate_filter { 
    my ( $filters_ref, $filter_name ) = @_;
    my $filter  = $filter_name ? $filters_ref->{$filter_name} : $filters_ref;
    return 1 unless 
        my $missing 
            = first { 
                  return 1 unless $filter->{ $_ };
                  return   unless my $validator = $validators->{ $_ };
                  local $_ = $filter->{ $_ };
                  return 1 if $validator->( $_ );
              } 
              qw<name filter_actions filter_criteria>
       ;
    if ( $missing ) { 
        Carp::croak( "Missing '$missing' in filter!" );
    }
}