XML File Creation in Perl - Updated Requirements [duplicate] - perl

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XML file creation in Perl
(2 answers)
Closed 8 years ago.
Sorry, I am posting this again but lot of requirements have been changed and I need advice.
My First input file is
Root1 TBLA KEY1 COLA A B
Root1 TBLA KEY1 COLB D E
Root1 TBLA KEY3 COLX M N
Root2 TBLB KEY4 COLX M N
Root2 TBLB KEY4 COLD A B
Root3 TBLC KEY5 COLD A B
My second input file is
Root1 TBLA KEY6
Root2 TBLB KEY7
Root3 TBLC KEY8
My third input file is
Root1 TBLA KEY9
Root1 TBLA KEY10
Root3 TBLC KEY11
Basically File representation is
1) First file represents the old and new values. First is root table, Second is actual table in which diff is there. Third column tells the key value. Fourth and Fifth represents old and new value.
2) Second file represents the primary key which exists in db1 only and not in db2. First is root table, Second is actual table in which key exists. Third column tells the key value
3) Third file represents the primary key which exists in db2 only and not in db1. First is root table, Second is actual table in which key exists. Third column tells the key value
The output to be created in xml format as
<Data>
<Root1>
<TBLA>
<NEW1>
<KEY>KEY6</KEY>
<NEW1>
<NEW2>
<KEY>KEY9</KEY>
<KEY>KEY10</KEY>
<NEW2>
<MODIFIED>
<KEY name =KEY1>
<COLA>
<oldvalue>A</oldvalue>
<newvalue>B</newvalue>
</COLA>
<COLB>
<oldvalue>D</oldvalue>
<newvalue>E</newvalue>
</COLB>
</KEY>
<KEY name =KEY3>
<COLX>
<oldvalue>M</oldvalue>
<newvalue>N</newvalue>
</COLX>
</KEY>
</MODIFIED>
</TBLA>
</Root1>
<Data>
THIS IS NOT COMPLETE OUTPUT. PART OF OUTPUT IS DISPLAYED
Can anyone suggest what would be the best way to do this. Should i convert this text file to hash of hashes first and then try using pltoxml(). does this make sense. Can XML::Simple or XML::Writer suffice this.
This is the first time I am working on xml and not sure which approach will help efficicently my solution.
A small example wrt to my req would be appreciated.
*Input file will always be sorted on Root and then TBLNAME
Output format
Output contains for every root, every table in that root and that for every table, key which exists in one and then key which exists in second only. This comes in section new1 and new2 respectively. Third section contains Modified which needs to read from first input file and list the key value and with that key value what columns are modified (their old and new value)
If I have to use XML::Simple, how do i create hashref from these files which i can pass it to XMLout. There is no key in any of these files.

Answer 1

This is simply a matter of using split to split the data into fields, storing it into a hash and then transforming it using XML::Simple.
Note that I stick things into an array to enforce the order you intended.
All the data is read from the DATA handle. You shouldn't need me to show you IO code.
The #processors array is simply the different processors you would use on the various files:
Code:
use 5.016;
use strict;
use warnings;
use XML::Simple qw(:strict);
my %roots;
my #processors
= ( sub {
my ( $root, $table, $key, $col, $old, $new ) = split /\s+/;
$roots{ $root }{ $table }[2]{MODIFIED}{ $col }
= { oldvalue => $old
, newvalue => $new
};
return;
}
, sub {
my ( $root, $table, $key ) = split /\s+/;
push #{ $roots{ $root }{ $table }[0]{NEW1}{KEY} }, $key;
}
, sub {
my ( $root, $table, $key ) = split /\s+/;
push #{ $roots{ $root }{ $table }[1]{NEW2}{KEY} }, $key;
}
);
my $processor = shift #processors;
while ( <> ) {
chomp;
if ( $_ eq '---' ) {
$processor = shift #processors;
}
else {
$processor->( $_ );
}
}
my $xs = XML::Simple->new( NoAttr => 1, RootName => 'Data', );
my $xml = $xs->XMLout( \%roots, KeyAttr => {} );
say $xml;
It produces:
<Data>
<Root1>
<TBLA>
<NEW1>
<KEY>KEY6</KEY>
</NEW1>
</TBLA>
<TBLA>
<NEW2>
<KEY>KEY9</KEY>
<KEY>KEY10</KEY>
</NEW2>
</TBLA>
<TBLA>
<MODIFIED>
<COLA>
<newvalue>B</newvalue>
<oldvalue>A</oldvalue>
</COLA>
<COLB>
<newvalue>E</newvalue>
<oldvalue>D</oldvalue>
</COLB>
<COLX>
<newvalue>N</newvalue>
<oldvalue>M</oldvalue>
</COLX>
</MODIFIED>
</TBLA>
</Root1>
<Root2>
<TBLB>
<NEW1>
<KEY>KEY7</KEY>
</NEW1>
</TBLB>
<TBLB></TBLB>
<TBLB>
<MODIFIED>
<COLD>
<newvalue>B</newvalue>
<oldvalue>A</oldvalue>
</COLD>
<COLX>
<newvalue>N</newvalue>
<oldvalue>M</oldvalue>
</COLX>
</MODIFIED>
</TBLB>
</Root2>
<Root3>
<TBLC>
<NEW1>
<KEY>KEY8</KEY>
</NEW1>
</TBLC>
<TBLC>
<NEW2>
<KEY>KEY11</KEY>
</NEW2>
</TBLC>
<TBLC>
<MODIFIED>
<COLD>
<newvalue>B</newvalue>
<oldvalue>A</oldvalue>
</COLD>
</MODIFIED>
</TBLC>
</Root3>
</Data>