Thnk you for your interest Thor.
Altought I don't have all the answers for your questions, here is what I have now:

My message looks like (I changed some codes): 

UNH+789+INVOIC:D:93A:UN:EAN007'
BGM+380+1234567890'
DTM+137:20040726:102'
RFF+DQ:9087654321'
RFF+ON:01234567'
NAD+BY+9182736453627::9'
RFF+VA:123987465'
RFF+API:123'
NAD+SU+123987658XXXX::9'
RFF+VA:200XXXXXX'
NAD+IV+1928374650981::9'
CUX+2:EUR:4'
LIN+1++230XXXXXXXXXX:EN'
IMD+F+M+:::Pencils'
QTY+47:70'
MOA+66:114.45'
PRI+AAB:5.36'
PRI+AAA:1.64'
ALC+A+++1+TD'
PCD+1:69.495'
UNS+S'
CNT+2:1'
MOA+139:138.48'
MOA+79:114.45'
MOA+125:114.45'
MOA+176:24.03'
MOA+98:375.20'
TAX+7+VAT+++:::21'
MOA+176:24.03'
UNT+30+798'

[download]
Now, what I want to achieve is:
  1. Validate this message against standard rules (and possibly some set of rules defined by the receiver);
  2. If is valid, create a Perl data structure, something better than this (I'm using a Data segment index from an external file): 
    $VAR1 = {
          'PDS' => {
                     '11' => {
                               'SEG' => [
                                          [
                                            'IV'
                                          ],
                                          [
                                            '1928374650981',
                                            '',
                                            '9'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Name and address'
+,
                                           'TAG' => 'NAD'
                                         }
                             },
                     '21' => {
                               'SEG' => [
                                          [
                                            'S'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Section control',
                                           'TAG' => 'UNS'
                                         }
                             },
                     '7' => {
                              'SEG' => [
                                         [
                                           'VA',
                                           '123987465'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Reference',
                                          'TAG' => 'RFF'
                                        }
                            },
                     '26' => {
                               'SEG' => [
                                          [
                                            '176',
                                            '24.03'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '17' => {
                               'SEG' => [
                                          [
                                            'AAB',
                                            '5.36'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Price details',
                                           'TAG' => 'PRI'
                                         }
                             },
                     '2' => {
                              'SEG' => [
                                         [
                                           '380'
                                         ],
                                         [
                                           '1234567890'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Beginning of messa
+ge',
                                          'TAG' => 'BGM'
                                        }
                            },
                     '22' => {
                               'SEG' => [
                                          [
                                            '2',
                                            '1'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Control total',
                                           'TAG' => 'CNT'
                                         }
                             },
                     '1' => {
                              'SEG' => [
                                         [
                                           '789'
                                         ],
                                         [
                                           'INVOIC',
                                           'D',
                                           '93A',
                                           'UN',
                                           'EAN007'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Message header',
                                          'TAG' => 'UNH'
                                        }
                            },
                     '18' => {
                               'SEG' => [
                                          [
                                            'AAA',
                                            '1.64'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Price details',
                                           'TAG' => 'PRI'
                                         }
                             },
                     '30' => {
                               'SEG' => [
                                          [
                                            '30'
                                          ],
                                          [
                                            '798'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Message trailer',
                                           'TAG' => 'UNT'
                                         }
                             },
                     '23' => {
                               'SEG' => [
                                          [
                                            '139',
                                            '138.48'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '16' => {
                               'SEG' => [
                                          [
                                            '66',
                                            '114.45'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '13' => {
                               'SEG' => [
                                          [
                                            '1'
                                          ],
                                          [],
                                          [
                                            '230XXXXXXXXXX',
                                            'EN'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Line item',
                                           'TAG' => 'LIN'
                                         }
                             },
                     '29' => {
                               'SEG' => [
                                          [
                                            '176',
                                            '24.03'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '27' => {
                               'SEG' => [
                                          [
                                            '98',
                                            '375.20'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '25' => {
                               'SEG' => [
                                          [
                                            '125',
                                            '114.45'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '6' => {
                              'SEG' => [
                                         [
                                           'BY'
                                         ],
                                         [
                                           '9182736453627',
                                           '',
                                           '9'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Name and address',
                                          'TAG' => 'NAD'
                                        }
                            },
                     '28' => {
                               'SEG' => [
                                          [
                                            '7'
                                          ],
                                          [
                                            'VAT'
                                          ],
                                          [],
                                          [],
                                          [
                                            '',
                                            '',
                                            '',
                                            '21'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Duty/tax/fee deta
+ils',
                                           'TAG' => 'TAX'
                                         }
                             },
                     '3' => {
                              'SEG' => [
                                         [
                                           '137',
                                           '20040726',
                                           '102'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Date/time/period',
                                          'TAG' => 'DTM'
                                        }
                            },
                     '9' => {
                              'SEG' => [
                                         [
                                           'SU'
                                         ],
                                         [
                                           '123987658XXXX',
                                           '',
                                           '9'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Name and address',
                                          'TAG' => 'NAD'
                                        }
                            },
                     '12' => {
                               'SEG' => [
                                          [
                                            '2',
                                            'EUR',
                                            '4'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Currencies',
                                           'TAG' => 'CUX'
                                         }
                             },
                     '20' => {
                               'SEG' => [
                                          [
                                            '1',
                                            '69.495'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Percentage detail
+s',
                                           'TAG' => 'PCD'
                                         }
                             },
                     '14' => {
                               'SEG' => [
                                          [
                                            'F'
                                          ],
                                          [
                                            'M'
                                          ],
                                          [
                                            '',
                                            '',
                                            '',
                                            'Pencils'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Item description'
+,
                                           'TAG' => 'IMD'
                                         }
                             },
                     '15' => {
                               'SEG' => [
                                          [
                                            '47',
                                            '70'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Quantity',
                                           'TAG' => 'QTY'
                                         }
                             },
                     '8' => {
                              'SEG' => [
                                         [
                                           'API',
                                           '123'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Reference',
                                          'TAG' => 'RFF'
                                        }
                            },
                     '4' => {
                              'SEG' => [
                                         [
                                           'DQ',
                                           '9087654321'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Reference',
                                          'TAG' => 'RFF'
                                        }
                            },
                     '24' => {
                               'SEG' => [
                                          [
                                            '79',
                                            '114.45'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Monetary amount',
                                           'TAG' => 'MOA'
                                         }
                             },
                     '19' => {
                               'SEG' => [
                                          [
                                            'A'
                                          ],
                                          [],
                                          [],
                                          [
                                            '1'
                                          ],
                                          [
                                            'TD'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Allowance or char
+ge',
                                           'TAG' => 'ALC'
                                         }
                             },
                     '10' => {
                               'SEG' => [
                                          [
                                            'VA',
                                            '200XXXXXX'
                                          ]
                                        ],
                               'CODE' => {
                                           'DES' => 'Reference',
                                           'TAG' => 'RFF'
                                         }
                             },
                     '5' => {
                              'SEG' => [
                                         [
                                           'ON',
                                           '01234567'
                                         ]
                                       ],
                              'CODE' => {
                                          'DES' => 'Reference',
                                          'TAG' => 'RFF'
                                        }
                            }
                   },
          'EDI' => 'UNH+789+INVOIC:D:93A:UN:EAN007\'
BGM+380+1234567890\'
DTM+137:20040726:102\'
RFF+DQ:9087654321\'
RFF+ON:01234567\'
NAD+BY+9182736453627::9\'
RFF+VA:123987465\'
RFF+API:123\'
NAD+SU+123987658XXXX::9\'
RFF+VA:200XXXXXX\'
NAD+IV+1928374650981::9\'
CUX+2:EUR:4\'
LIN+1++230XXXXXXXXXX:EN\'
IMD+F+M+:::Pencils\'
QTY+47:70\'
MOA+66:114.45\'
PRI+AAB:5.36\'
PRI+AAA:1.64\'
ALC+A+++1+TD\'
PCD+1:69.495\'
UNS+S\'
CNT+2:1\'
MOA+139:138.48\'
MOA+79:114.45\'
MOA+125:114.45\'
MOA+176:24.03\'
MOA+98:375.20\'
TAX+7+VAT+++:::21\'
MOA+176:24.03\'
UNT+30+798\'
'
        };

    [download]
    I wrote a small script to do this part: 
    #!/usr/bin/perl -w

use strict;
use CGI;
use CGI::Carp qw/fatalsToBrowser/;
use Data::Dumper;
my $q = new CGI;
my $result = ParseEDI(
    {
        EDI => '/path/to/edis/invoice.edi',
        DIC => '/path/to/dics/d93a_invoic.dat',
    }
);

print $q->header, $q->start_html, $q->start_pre;
print Dumper $result;
print $q->end_pre, $q->end_html;


sub ParseEDI {

    my $self = shift;
    
    my $output = {
        EDI => undef, # Original message
        PDS => undef, # Perl Data Structure
    };
    open ( EDI, "<", $self->{EDI} ) or die ( "Error opening EDI messag
+e");
    
    my $i = 1;
    while ( <EDI> ) {
        
        $output->{EDI} .= $_;

        my ($CODE, $VARS) = ($_ =~/^(\w{3})\+(.*)'$/);
        $output->{PDS}->{$i} = {
            CODE => {
                TAG => $CODE,
                DES => DataIndex(
                    {
                        DIC => $self->{DIC}
                    }
                )->{$CODE},
            },
            SEG => [map ([map ($_ , split /:/)] , split /\+/ , $VARS)]
+,
        };
        $i++;
    }
    close ( EDI );

    return $output;
}

sub DataIndex {

    my $self = shift;
    
    open (DIC, "<", $self->{DIC} ) or die "Error opening the data inde
+x";
    my $res = {};
    while (<DIC>) {
        my ($CODE, $DESC) = ($_ =~/^(\w{3}) (.*)$/ );
        $res->{$CODE} = $DESC;
    }
    close DIC;
    return $res;

}

    [download]
  3. Show some informations to the user.

My problems are:

  1. How to apply the rules (the 'standard' and others defined by the receiver)? There are 100s (perhaps 1000s) of constraints to check. How to do the mappings?
  2. How to construct a solid, fast and accurate data structure that allows me to extract any kind of information from an EDI message?
Hope this helps.
Miguel

Edit: g0n - Added readmore tags

In reply to Re^2: Parsing EDI messages by Miguel
in thread Parsing EDI messages by Miguel

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