It looks like you're just trying to serve the pdf.

    $r->content_type('application/pdf');
    
    my $output = do {
        open my $pdf, $file or die "$file: $!";
        binmode $pdf;
        local $/;
        <$pdf>
    };

    # Return the page
    $r->header_out( 'Content-Length' => length($output) );
    $r->send_http_header;
    $r->print($output);

    return OK;
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