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

I need to run a remote command. I will not know the language before hand. This seemed like a simple problem that shell could handle but I need more error checking. But most importantly I needed a hash so off to perl.

I've got Net::OpenSSH working if I just use capture with no args but I need to send an arg & this causes an err to be flagged.

my @output = $ssh->capture("$cmd $arg1 $arg2");

 if($ssh->error) {
     if($ssh->error) {
        $myhash{"$cmd" = "FAIL";
     } else {
        $myhash{"$cmd" = "Ok";
     }
}

[download]

I've got filehandles set up and everything gets printed to these (a log & an err log). But when I add the args to the $cmd the err file says it doesn't know a command by that name (the 1st arg is a build number so its a number).

I've spent lots of hours searching & tried many things but I need the details of the output not just a 0 or 1.

I've read the CPAN docs & tried many things but none worked but to send the $cmd...

thoughts?

Replies are listed 'Best First'.
Re: Net::OpenSSH capture and cmd w/args
by Anonymous Monk on Aug 04, 2011 at 15:39 UTC
    It will probably work if you use $cmd with an absolute path, e.g. /usr/local/bin/whatevercmd?
    Add warn "($cmd) ($arg1) ($arg2)" as diagnostic output.
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Re: Net::OpenSSH capture and cmd w/args
by eonarts (Novice) on Aug 04, 2011 at 16:00 UTC

    Valid code as per request.

    #!/usr/bin/perl
use strict;
use warnings;
use Time::HiRes qw/ usleep gettimeofday tv_interval/;
use File::Basename;
use Net::OpenSSH;
use Expect;
#################################
## Configurables here
#################################
our $test_host="myhost";
our $ssh_user="myuser";
our $HOME="/home/myuser";
our $dir="${HOME}/mytests";
our $ARG1=777;
#################################
## Variables here
#################################
our %test_results ;
our $Y = "OK";
our $N = "FAIL";
our @output_to_print ;
my ($file, $fname,$text_to_print);
our $now=`date +%m%d%Y_%H%M%S`;
chomp($now);
my ($stderr_fh, $stdout_fh);
my $stdoutfile = "/tmp/$ARG1$now.log";
my $stderrfile = "/tmp/$ARG1$now.err";
our $LOG="/tmp/${ARG1}_${now}.log";
#################################
## Main
#################################
open $stdout_fh, '>>', "$stdoutfile" or die "cannot open stderr file";
open $stderr_fh, '>>', "$stderrfile" or die "cannot open stdout file";

# open a connection to the test server
my $ssh = Net::OpenSSH->new("$ssh_user\@$test_host",default_stderr_fh 
+=> $stderr_fh,
                                                    default_stdout_fh 
+=> $stdout_fh );
$ssh->error and die "SSH connection failed: " . $ssh->error;

# Get the files to run
  my @files = $ssh->capture("ls $dir ");
  $ssh->error and die "remote ls command failed: " . $ssh->error;

foreach $file(@files){
        my $full_file="${dir}/$file";
        my $fname = $file;
        $fname =~ s{\.[^.]+$}{};
        print "$fname \n";
        $text_to_print="test: $full_file Log: $LOG \n";
print $stdout_fh "$text_to_print \n";
  my @output = $ssh->capture("$full_file ");
  if($ssh->error) {
        $test_results{"$fname"} = "$N";
  }
  if(grep(/\b$Y\b/,@output)) {
        $test_results{"$fname"} = "$Y";
  } else {
        if (grep(/\b$N\b/,@output)) {
           $test_results{"$fname"} = "$N";
        }
  }
print $stdout_fh "@output \n";
}
print $stdout_fh "\nTest results\n#################\n";
  while ((my $test, my $result) = each(%test_results)) {
        print $stdout_fh  "$test,  $result\n";
  }

    [download]

    I've tried the following with no success 

    # DOESNT WORK?? the $ARG1 causes problems? 
my @output = $ssh->capture("$full_file $ARG1 $LOG");
  # doesnt work 
my( $in, @output, $err, $pid ) = $ssh->open3("$full_file $ARG1 $LOG");
  # DOESNT WORK?? 
my @output = $ssh->capture(stdin_data => "$full_file $ARG1 $LOG ");

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      $full_file probably contains a linefeed. Please chomp first...
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        ARG! really? really? I thought that was a silly reply - which probably meant it was the correct answer.

        ::hangs head in shame::

        THAT WAS THE ANSWER! thank you thank you thank you! 

        my $full_file="${dir}/$file";
        chomp($full_file);

        [download]

        I need more sleep & coffee...

[reply]
[d/l]
      Does $full_file exist? Is it executable? Maybe you want something like $ssh->capture("cat $full_file");?
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