ACARS message parsing

Question

I need to parse ACARS messages to XML format.

There is simple messages:

RX_IDX: 13
ACARS mode: O, message label: 5V
ACARS ML description: VDL switch advisory
Aircraft reg: .EI-EUX, flight id: UN0323
Block id: 57,  msg. no: S91A
Message content:-

----------------------------------------------------------[05/05/2013 08:58]

RX_IDX: 14
ACARS mode: 2, message label: 1L
ACARS ML description: Off message
Aircraft reg: .D-AIRO, flight id: LH1490
Aircraft vendor: Airbus, short type: A321, full type: A321-131, cn: 0563
Carrier IATA: LH, ICAO: DLH, remarks: Lufthansa
Airlines: Lufthansa
Block id: 56,  msg. no: M03A
Message content:-
00002216743GO,X,55655
----------------------------------------------------------[05/05/2013 09:24]

Each message starts with RX_IDX and ends with date (eg. [05/05/2013 09:24]).

I found perl script, but it doesn't recognize attributes after commas.

#!/usr/local/bin/perl
use strict;
use warnings;

my @keys = ( 
    'RX_IDX',
    'ACARS mode',
    'message label',
    'ACARS ML description',
    'Aircraft reg',
    'flight id',
    'Aircraft vendor',
    'short type',
    'full type',
    'cn',
    'Carrier IATA',
    'ICAO',
    'remarks',
    'Airlines',
    'Block id',
    'msg. no',
    'Message content'
);

my( %keys, %tags );
$keys{$_} = 1 for @keys;
$tags{$_} = $_ . '' for @keys;
$tags{$_} =~ s/ /_/g for @keys;

my $file = 'data8.txt';
open( my $fh, '<', $file) or die("Can't open $file: $!");

my %record = map { $_, '' } @keys;
while( my $line = <$fh> ) {
    chomp($line);
    if( $line =~ m{ \A (.+?) : \s* (\S+) }x ) {
        $record{$1} = $2 if $keys{$1};
        if( $1 eq $keys[$#keys] ) {
            print "<Message>\n";
            print "<$tags{$_}>$record{$_}</$tags{$_}>\n" for @keys;
            print "</Message>\n";
            %record = map { $_, '' } @keys;
        }
    }
}

Regards

Answer 1

The problem is that the if condition of the regex only will match once for each line. Try to match the regular expression until if fails in a while loop. I added the \\G assertion when in next loop it will begin when left last time. Also changed it a little bit to avoid matching at the beginning of line ( \\A ) and added a possible match of a comma at the end, it will be like this (I copied only relevant part of code):

while( my $line = <$fh> ) { 
    chomp($line);
    while ( $line =~ m{ \G \s* (.+?) \s* : \s* ([^,]+) \s* (?:,|$) }xg ) { 
        $record{$1} = $2 if $keys{$1};
        if( $1 eq $keys[$#keys] ) { 
            ...
        }   
    }   
}