perl pdf::api2 checking if a pdf file is encrypted - perl

Question

I have a website using a perl script for customers to upload a pdf file for me to print and post the printed pages to them.
I am using PDF::API2 to detect the page size and number of pages in order to calculate the printing costs.
However, if the pdf file is password protected this does not work and I get this error -
Software error:
Objind 9 does not exist at index 0 at /home5/smckayws/public_html/hookincrochet.com/lib//PDF/API2/Basic/PDF/File.pm line 758.
I am trying to use the isEncrypted feature in the pdf::api2 module to catch that the file is encrypted in order to direct the customer to a different page so they can enter the page size and page number manually, but it is not working for me.
I just get the same error message as above.
I have tried the following code snippets found elsewhere.
my $pdf = PDF::API2->open( "$customer_directory/$filename" );
if ( defined $pdf && $pdf->isEncrypted )
{
print "$pdf is encrypted.\n";
exit;
}
while (glob "*.pdf") {
$pdf = PDF::API2->open($_);
print "$_ is encrypted.\n" if $pdf->isEncrypted();
}
Any help would be greatly appreciated.

Answer 1

My guess is that the PDFs might use a feature that your version of PDF::API2 doesn't support. This is a workaround for the problem.
Wrap the call to isEncrypted in an eval, catch the error and handle it.
This will only work if the error does not occur on unencrypted files.
my $pdf = PDF::API2->open( "$customer_directory/$filename" );
if ( defined $pdf ) {
eval { $pdf->isEncrypted };
if ($#) {
# there was some kind of error opening the file
# could abort now, or look more specific, like this:
if ($# =~ m/Objind 9 does not exist at index 0/) {
print "$pdf is encrypted.\n";
exit;
}
}
# file is not encrypted, opening worked, continue reading it
}