A simple perl program to send data from different files - perl

Question

I wrote a perl program which send the updated data from a file to remote server periodically. But now i want it to read it from differnt files and send the updated data such that the reciever should know how to seperate the data from the mixed data. Do i just need to put some kind of delimiter? Is there any standards already there for such things?
#############
#Change parameters
############
$PeerAddr='192.168.0.7';
$PeerPort='7070';
##############
# Import packages
##############
use Text::Diff;
use IO::Socket;
#############
# Define global variables
#############
$lineCount=0;
$loopCount=0;
our $stats2 = 0;
for($count = 0; $count <= 10000; $count++){
my $data_dir="archive/otat/*dat";
my $data_file= `ls -t $data_dir | head -1`;
chomp($changed_data_file);
print "old data_file is $changed_data_file \n";
chomp($data_file);
if($data_file ne $changed_data_file){
$lineCount2=0;
$changed_data_file=$data_file;
print ("String:$data_file :$changed_data_file are not equal\n");
}
while(defined($data_file)){
print "$data_file \n";
open (DAT,$data_file) || die("Could not open file! $!");
#iofile = <DAT>;
$lineCount = #iofile;
splice(#diffLines);
print "printing: $lineCount\n";
print "printing 2: $lineCount2 \n";
chomp $lineCount;
chomp $lineCount2;
if($lineCount != $lineCount2){
$j=0;
for($i=$lineCount2;$i <= $lineCount; $i++){
$diffLines[$j] = $iofile[$i];
$j++;
}
$num=#diffLines;
print "count of diff lines:$num\n";
$lineCount2 = $lineCount;
$loopCount=0;
}
if($loopCount>2){
$loopCount=0;
print "Look for recent file \n";
last;
}
$loopCount++;
sleep(5);
############################
&socket_con(#diffLines);
}
}
#### Methods/Functions
sub socket_con {
if ($sock== 0){
$sock = new IO::Socket::INET (
PeerAddr => $PeerAddr,
PeerPort => $PeerPort,
Proto => 'tcp'
);
die "Could not create socket: $!\n" unless $sock;
}
print $sock #_;
#close($sock);
}

Answer 1

I've used JSON a lot with good results http://metacpan.org/pod/JSON You can store your data in a hash, serialize it, send the text to the client and have it turn the string back into a Perl hash for easy use. For example:
# on the server
use JSON;
...
# store changed lines in a hash
$diffLines->{$data_file}[$j]=$io_file[$i];
...
# Serialize the hash reference into a string which you then send to the client
$diffLinesSerialized = encode_json $diffLines;
# on the clinet
use JSON;
...
# convert received data from serialized string into hash
$diffLines = decode_json $diffLinesSerialized;
# $diffLines is now a has reference which can be accessed like normal
foreach my $data_file (keys %$diffLines) {
foreach my $line (#{$diffLines->{$data_file}}) {
...
}
}
All this being said, as much as I don't really like XML from a programming perspective, it is a prevalent standard for this kind of thing. If this is just a specialized, internal tool that won't grow into something larger it probably doesn't matter, but if you think this could turn into a more general service, say for non-perl clients, it would be good to consider XML as an option. Programming from a service-oriented perspective can make it easier to grow things down the road.