Read and send a file to the browser and then delete

Question

My Question

I have a script that generates a PDF as a 'one-off'. My script then reads the file and sends it to the browser.

The problem that I have is that I need to delete the file once it has been successfully sent to the browser.

I know that there can be issues with detecting whether or not the user has completely downloaded the file, this being the reason why I am asking this question...

Is there a reliable way to send a file to the browser, and then delete it once it has been fully sent/downloaded to the clients browser/computer?

My Research

I have searched around a lot and can see that this may not be possible. The following questions offered a little information on the topic:

Both these questions seem to contradict each other with one saying you can do it if you use ignore_user_abort etc, and the other saying that it cannot be done...

I am aware that another potential solution is to simply run a cronjob/scheduled task to delete any files that are over X mins old... I will resort to this as my last option

What I have tried

So far, I have played around with a few things but nothing yet has worked... My code as it stands looks like this:

// Set the headers to PDF
header('Content-type: application/pdf');

// Read the file and send it to the browser
readfile($this->paths['WWW'].'/test.pdf');

// Delete the file
unlink($this->paths['WWW'].'/test.pdf');

UPDATE

I have just re-tested my code and it appears to be working just fine... There was a permissions error on the file so it wasnt deleting when I called unlink.

However, I am still a little cautious about using this method. Can I be sure that the file will be delivered and then deleted after it has been sent?

I have tested this with a large PDF file and it does work so the above solution may actually be correct. I would still appreciate any other thoughts if anybody wishes to share or can see any hidden issues with this method.

Just generate the PDF and send it to the user. Don't save it as a file in the first place. — Quentin, Sep 10 '13 at 14:15
@Quentin Sadly I am using a COM to generate the PDF so it has to create it... — Ben Carey, Sep 10 '13 at 14:31

score 0 · Answer 1 · answered Sep 10 '13 at 15:09

This might be a silly thing. But most PDF Gernerating libraries have a stream option.

So you url syntax would be steampdf.php?id=12. This outputs a file names My_Super_Duper_pdf.pdf and that's it.

An Example for TCPDF

//Databaselogic goes here 
$db->select_all_records_and_merge_the_pdf();
$pdf = new PDF();
$pdf->SetMargins(PDF_MARGIN_LEFT, 40, PDF_MARGIN_RIGHT);
$pdf->SetAutoPageBreak(true, 40);
$pdf->setFontSubsetting(false);

//do pdf logic:
        $tblHeading = '<table>
            <tr>
                <td colspan="2" style="font-family: ralewaybold; font-size: 16pt;">Factuur</td>
            </tr>
            <tr>
                <td style="font-family: ralewayreg; font-size: 12pt;">x:</td>
                <td style="font-family: ralewayreg; font-size: 12pt;">'.$varInvoiceNumber.'</td>        
            </tr>
            <tr>
                <td style="font-family: ralewayreg; font-size: 12pt;">x:</td>
                <td style="font-family: ralewayreg; font-size: 12pt;">'.$varInvoiceDate.'</td>
            </tr>
        </table>';

        $pdf->writeHTMLCell(100, 40, 20, 100.5, $tblHeading);

// add a page
$pdf->AddPage();

return $pdf->Output("My_Super_Duper_pdf.pdf","S");

Read and send a file to the browser and then delete

My Question

My Research

What I have tried

UPDATE

1 Answers1