hextor has asked for the wisdom of the Perl Monks concerning the following question:

Please excuse my uber noob and sometimes redundant questions, however I am new to Perl so I have run into a few road blocks, specifically with getopt::std. I created an rsync perl script that will transfer gz files from a local destination to a remote destination using a key, a semaphore, etc. Anyway, what I am currently trying to do is to pass arguments to the command line using getopt::std that would allow to just drop flags if I wish to rsync data using different IP/host, key, username, etc. I have been told that this is possible but I don't quite understand how to implement that with getopt::std. I was going to go with ARGV, but my team would prefer I go with getopt. I have read up on getopt::std but to be honest, there isnt much covered on the module. That or I am not quite understanding how it works in a script if I don't have specify variables for the flags. Below is the script I am trying to implement getopt::std to. Any help towards the right direction would be greatly appreciated. 

#!/usr/bin/perl -w


### set initial variables

$user            = '<USERNAME>';
$host            = '<IP/HOSTNAME>';
$priv_key        = '</KEY/DIR/FILE>';
$remote_dir      = "<REMOTEDIR>";
$source_dir      = '<SOURCEDIR>';
$log_dir         = '<LOGDIR>';

### set system commands/configs/flags

my $rm_cmd       = '/bin/rm -rf';
my $touch_cmd    = '/bin/touch';
my $ssh_cmd      = '/usr/bin/ssh -i';
my $DEBUG        = 2;

### set rsync commands/flags

my $rsync_cmd    = '/usr/bin/rsync -Pav -e';
my $del_flag     = "--remove-source-files";


### set file names/extensions

my $semaphore    = "rsync_running.lock";
my $log_file     = "rsync.output.log";
my $file_ext     = "*.gz";


sub filesize {

    use File::Find;

    find( sub { -f and ( $size += -s ) }, $source_dir );
    $size = sprintf( "%.02f", $size / 1024 / 1024 );
    open STDOUT, ">> $log_dir/$log_file" or die "$0: open: $!";
    open STDERR, ">>& STDOUT" or die "$0: dup: $!";

    print "Directory '$source_dir' contains $size MB\n";

}

sub getLoggingTime {

    ( $sec, $min, $hour, $mday, $mon, $year, $wday, $yday, $isdst ) =
      gmtime(time);
    $nice_timestamp = sprintf(
        "%04d%02d%02d %02d:%02d:%02d",
        $year + 1900,
        $mon + 1, $mday, $hour, $min, $sec
    );

    return $nice_timestamp;

}

sub rsyncfiles {

    if ( -f "$source_dir/$semaphore" ) {
        print "Rsync running, skipping this session.\n" if ( $DEBUG > 
+2 );

    }

    else {

system("$touch_cmd $source_dir/$semaphore");

        my $push_cmd =
"$rsync_cmd \"$ssh_cmd $priv_key\" $del_flag $source_dir/$file_ext $us
+er\@$host:$remote_dir";
                print "Running: $push_cmd\n" if ( $DEBUG > 1 );
                my $return = system($push_cmd);
                if ($return) {
                    print "rsync failed";
                }
            }
        system("$rm_cmd $source_dir/$semaphore");
    }


@timeData  = gmtime(time);
my $timestamp = getLoggingTime();

open STDOUT, ">> $log_dir/$log_file" or die "$0: open: $!";
open STDERR, ">>& STDOUT" or die "$0: dup: $!";

print "The script ran at $timestamp \n";

&filesize;
&getLoggingTime;
&rsyncfiles;

[download]

Thanks all!

Replies are listed 'Best First'.
Re: getopt::std to pass arguments to command line help
by toolic (Bishop) on Jan 20, 2015 at 17:31 UTC
    I recommend Getopt::Long, storing all options in a hash: 
    use warnings;
use strict;
use Getopt::Long qw(GetOptions);

my %opt = (logdir => 'foo');
GetOptions(\%opt, qw(logdir=s)) or die;
print "logdir=$opt{logdir}\n";

__END__

Run it like:
    myprog.pl -logdir bar

Output:
    logdir=bar

    [download]
[reply]
[d/l]
      hextor look at that good example by toolic and pay attention to the GetOptions ... or die; part.
      This is very important because you dont want your program to execute with wrong or not accepted args.
      Personally i ended using everytime yet another idiom, even more cautious: 
      use Getopt::Long;
use Pod::Usage;     # if you have documentation embedded is better


unless (GetOptions( "option=s" => \$option  ... ))  {
       
       pod2usage(-verbose => 1,-exitval => 'NOEXIT');    # automatic u
+sage printing (if you have an usage section in POD)
       &wait_for_input;                                  # if the prog
+ was opend in a 'double click' fashion there is no time 
                                                         # to review e
+rrors, if so you can just use something like:
                                                         # sub wait_fo
+r_input{ 
                                                         #   print "\n
+\nPress Return when ready\n";
                                                         #   while (<S
+TDIN>){last if $_ }
                                                         # }
       exit;                                             # now you can
+ exit or die with yet another error string
}

      [download]

      HtH
      L*
      There are no rules, there are no thumbs..
      Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.
[reply]
[d/l]
[select]
      Thank you. I will look into getopt::long.
[reply]
Re: getopt::std to pass arguments to command line help
by karlgoethebier (Abbot) on Jan 20, 2015 at 18:49 UTC
[reply]
Re: getopt::std to pass arguments to command line help
by Anonymous Monk on Jan 20, 2015 at 17:29 UTC
    I have been told that this is possible but I don't quite understand how to implement that with getopt::std.
    That's because you should use Getopt::Long. Also 
    open STDOUT, ">> $log_dir/$log_file

    [download]
    Don't open files like this if you don't know what Perl does with two-argument open. Especially if $log_dir and $log_file come from user input. Do it like this: 
    open STDOUT, '>>', $log_dir/$log_file

    [download]
    Consider using File::Spec::Functions for manupilating file names. 
    &filesize;

    [download]
    Don't call functions like this if you don't know what it actually does. Call them like this: 
    filesize();

    [download]

    use warnings; instead of -w. Also use strict;

[reply]
[d/l]
[select]
      open STDOUT, '>>', "$log_dir/$log_file", but really 
      use File::Spec::Functions;
...
open STDOUT, '>>', catfile( $log_dir, $log_file )
  or die "Can't open $log_file - $!\n";

      [download]
[reply]
[d/l]
[select]
      That makes sense. I see how that works better, thank you. The log file is created if it doesn't exist, however is there a way to specify permissions when the file is being created? Example, what if I wanted to the file to have 755 perms? I know it's not recommended, but for the sake of the question, what would you recommend?
[reply]
[reply]
Re: getopt::std to pass arguments to command line help
by jellisii2 (Hermit) on Jan 21, 2015 at 13:04 UTC
[reply]

Back to Seekers of Perl Wisdom