traffic_ops_ort doesn't update empty config file problem

[Jifeng Yang (jifyang)]

Hi,

We met a problem about traffic_ops_ort:

The ATS config file “remap.config” happened to be zero size. After that, the 
“remap.config” file couldn't be updated by the traffic_ops_ort.

Checking the code in the file “/opt/ort/traffic_ops_ort.pl”, there is:

    sub can_read_write_file {
           my $filename = shift;
           ......
           if ( -z $file ) {
                    ( $log_level >> $ERROR ) && print "ERROR $file has 
size=0!\n";
                    $cfg_file_tracker->{$filename}->{'audit_failed'}++;
                    return 0;
            }
            ......
            return 1;
    }

By the code, the zero size file isn't treated as can_read_write_file.

Can we treat zero size file as can_read_write_file? Is there any consideration 
about this?

The configuration file may become zero size file by some reason (such as by 
accident). If zero size config file isn't treated as can_read_write_file, it 
can't be updated any more if a configuration file becomes zero size.

Thanks,
Jifeng