Hi friends! I'm no Perl expert but am trying to parse a file for some information which I would like to use to output some JSON formatted text for consumption by Zabbix. The file I'm parsing contains a derivative of the following text: 


#Bob monitoring

cd /opt/bob-monitor

### version 2
java -jar libs/BobMonitor.jar -xruntime/bob311_2_acc_list.xml -l/tmp/b
+ob311/fail.logs -s/tmp/bob311/results.txt 2>&1
java -jar libs/BobMonitor.jar -xruntime/bob411_2_acc_list.xml -l/tmp/b
+ob411/fail.logs -s/tmp/bob411/results.txt 2>&1

### version 3
java -jar libs/BobMonitor.jar -xruntime/bob312_3_acc_list.xml -l/tmp/b
+ob312/fail.logs -s/tmp/bob312/results.txt 2>&1
java -jar libs/BobMonitor.jar -xruntime/bob412_3_acc_list.xml -l/tmp/b
+ob412/fail.logs -s/tmp/bob412/results.txt 2>&1

### version 4
java -jar libs/BobMonitor.jar -xruntime/bob313_4_acc_list.xml -l/tmp/b
+ob313/fail.logs -s/tmp/bob313/results.txt 2>&1
java -jar libs/BobMonitor.jar -xruntime/bob413_4_acc_list.xml -l/tmp/b
+ob413/fail.logs -s/tmp/bob413/results.txt 2>&1

....

[download]
My Perl script looks as follows: 
#!/usr/bin/perl

print "{";
print " \"data\":\n\t[\n";

my $filename = '/opt/scripts/fester_monitor.sh';
open(my $fh, '<:encoding(UTF-8)', $filename)
        or die "Could not open file '$filename' $!";

while (my $row = <$fh>) {
        chomp($row);

        for($row) {
                s/^cd.*//;
                s/^#.*//;
                ($festerinstance) = m/(fester(\d+))/;

                print ",\n";

                $return = "\t{ \"{#FESTERINSTANCE}\":\"$festerinstance
+\"}" unless /(^\s*$|^\,$)/;
                print $return;
        }
}

print "\t]\n";
print "}\n";

[download]
The desired output is something like the following: 
{ "data":
        [
        { "{#BOBINSTANCE}":"bob311"},
        { "{#BOBINSTANCE}":"bob411"},
        { "{#BOBINSTANCE}":"bob411"},
        { "{#BOBINSTANCE}":"bob411"},
        { "{#BOBINSTANCE}":"bob312"},
        { "{#BOBINSTANCE}":"bob412"},
        { "{#BOBINSTANCE}":"bob412"},
        { "{#BOBINSTANCE}":"bob412"},
        { "{#BOBINSTANCE}":"bob313"}
....
        ]
}

[download]
Yet, I'm getting this: 
{ "data":
        [
,
,
,
,
,
,
        { "{#BOBINSTANCE}":"bob311"},
        { "{#BOBINSTANCE}":"bob411"},
        { "{#BOBINSTANCE}":"bob411"},
        { "{#BOBINSTANCE}":"bob411"},
        { "{#BOBINSTANCE}":"bob312"},
        { "{#BOBINSTANCE}":"bob412"},
        { "{#BOBINSTANCE}":"bob412"},
        { "{#BOBINSTANCE}":"bob412"},
        { "{#BOBINSTANCE}":"bob313"}
....
        ]
}

[download]
The issue is the extra commas at the top of the output- which will not be well-formed JSON. Looking at my code, can any one of you perhaps spot something that I may be doing wrong?

In reply to Problem printing JSON type output by jonathan.vanderwatt

Title:
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