Paddy Paddy - 4 months ago 26
Perl Question

Building report from xml using perl

I'm newbie in XML parsing, I made a code to build reports from XML file using Perl But I'm facing problem that not get exact output. Following is my file.

<ROOT>
<BILL id = '1'>
<CHARGES ChargeCategoryDescription="MAYESEVILLE CHARGES" Amount="70.09" Parent="1"/>
<CHARGES ChargeCategoryDescription="MA - WATER" Amount="43.04" Parent="0">
<LineItemDetail UtilityTransDetailID="6605683" ComponentType="Flat Rate" ComponentDescription="WATER MIN">
<LIDetailConsumption PreviousRead="914.0000000" CurrentRead="915.0000000" ActualConsumption="1.0000000"/>
</LineItemDetail>
</CHARGES>
<CHARGES ChargeCategoryDescription="MA - SEWER" Amount="27.05" Parent="0">
<LineItemDetail UtilityTransDetailID="6605685" ComponentType="Flat Rate" ComponentDescription="SEWER MINIMUM">
<LIDetailConsumption PreviousRead="91.0000000" CurrentRead="95.0000000" ActualConsumption="4.0000000"/>
</LineItemDetail>
</CHARGES>
</BILL>
<BILL id = '2'>
<CHARGES ChargeCategoryDescription="MAYESEVILLE CHARGES" Amount="21.52" Parent="1"/>
<CHARGES ChargeCategoryDescription="MA - WATER" Amount="21.52" Parent="0">
<LineItemDetail UtilityTransDetailID="6605690" ComponentType="Flat Rate" ComponentDescription="WATER MIN">
<LIDetailConsumption PreviousRead="790.0000000" CurrentRead="791.0000000" ActualConsumption="1.0000000"/>
</LineItemDetail>
</CHARGES>
</BILL>
<BILL id = '3'>
<CHARGES ChargeCategoryDescription="MAYESEVILLE CHARGES" Amount="60.7" Parent="1"/>
<CHARGES ChargeCategoryDescription="MA - WATER" Amount="38" Parent="0">
<LineItemDetail UtilityTransDetailID="6605673" ComponentType="Flat Rate" ComponentDescription="WATER MIN">
<LIDetailConsumption PreviousRead="5.0000000" CurrentRead="5.0000000" ActualConsumption=".0000000"/>
</LineItemDetail>
</CHARGES>
<CHARGES ChargeCategoryDescription="MA - SEWER" Amount="22.7" Parent="0">
<LineItemDetail UtilityTransDetailID="6605675" ComponentType="Flat Rate" ComponentDescription="SEWER MINIMUM">
<LIDetailConsumption PreviousRead="5.0000000" CurrentRead="5.0000000" ActualConsumption=".0000000"/>
</LineItemDetail>
</CHARGES>
</BILL>




Follows is my code

use XML::Twig;

my $filename = "sample.xml";

my $twig = XML::Twig->new();
$twig->parsefile($filename);
my $root = $twig->root;

open(OUT, ">output.txt") or die "$!";

foreach my $bill($root->children('BILL'))
{
$Field[0] = $bill->att('id');
foreach my $service($bill->children('CHARGES'))
{
$Field[1] = $service->att('ChargeCategoryDescription');
if ($Field[1] =~ /MA \- WATER/)
{
$Field[1] = $service->att('ChargeCategoryDescription');
}
elsif ($Field[1] =~ /MA \- SEWER/)
{
$Field[1] = $service->att('ChargeCategoryDescription');
}
$Field[2] = $service->att('Amount');
foreach my $read ($service->children('LineItemDetail'))
{
$Field[3] = $read->first_child('LIDetailConsumption')->att('CurrentRead');
$Field[4] = $read->first_child('LIDetailConsumption')->att('PreviousRead');
$Field[5] = $read->first_child('LIDetailConsumption')->att('ActualConsumption');
}

}
push(@servicearr,"$Field[1] $Field[3] $Field[4] $Field[5] $Field[2]");
if (@servicearray>7){die "MORE THEN TWO SERVICES FOUND IN ID#$Field[0] \n";}
write OUT;
@servicearr = ();

}

format OUT =
@<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

@<<<<<<<<<<<<<<<<<
$Field[0]


@<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$servicearr[0]
@<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$servicearr[1]
@<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$servicearr[2]


.


I wanted the OUTPUT like as Follows:


Bill No: 1

Service CurrentRead PreviousRead Consumption Amount
MA - WATER 915.0000000 914.0000000 1.0000000 43.04
MA - SEWER 95.0000000 91.0000000 4.0000000 27.05


Bill No: 2

Service CurrentRead PreviousRead Consumption Amount
MA - WATER 791.0000000 790.0000000 1.0000000 21.52


Bill No: 3

Service CurrentRead PreviousRead Consumption Amount
MA - WATER 5.0000000 5.0000000 .0000000 38
MA - SEWER 5.0000000 5.0000000 .0000000 22.7


Please need help, Thanks in advanced.

Answer

To get your output, I'd probably tackle it like this:

#!/usr/bin/perl
use strict;
use warnings 'all';

use XML::Twig;

my $twig = XML::Twig -> new -> parsefile('sample.xml'); 

my @headers = qw ( CurrentRead PreviousRead ActualConsumption );
my @categories = ( 'MA - WATER', 'MA - SEWER' ); 

open ( my $output, '>', "output.txt" ) or die $!; 
foreach my $bill ( $twig -> get_xpath('//BILL') ) { 
    print {$output} "Bill ID: ", $bill -> att('id'),"\n\n"; 
    print {$output} join "\t", "Service\t", @headers, "\n"; 
    foreach my $category ( @categories ) { 
        my $charge = $bill -> get_xpath(".//CHARGES[\@ChargeCategoryDescription=\"$category\"]", 0); 
        next unless $charge;
        print {$output} join "\t", $category, (map { $charge -> get_xpath('.//LIDetailConsumption',0) -> att($_) } @headers), "\n";
    }
    print {$output} "\n";

}

Note - using tab stops to delinate formatting, rather than a format. That's not quite what you asked for, I know, but IMO it's more useful.