php - Merging 2 pdf with Zend Framework

Question

I'm trying to merge 2 PDF, one on my server (not dynamically generated) and one generated just before the merge and not saved anywhere on the server (I just want my client to download it). So I only have the pdf's content. Both PDF have the same format (A4).

The merged file will have 2 pages and won't be saved on server as well.

Since, I'm using Zend Framework, I would prefer a solution with it (can't find one online...) else any advice ?

(common solution found online but doesn't work)

Edit : because people are lazy to click. The code is in the link anyway since it's wrong and doesn't work.

I try the script below, but I get the error:

Uncaught exception 'Zend_Pdf_Exception' with message 'Page is attached to one documen, but rendered in context of another

Answer 1

Alright, with the guide from @Gordon 's comment in my question, I got a solution.

1. You must have at least Zend Framework 1.11 (I was in 1.9, first error) (found thanks to the 3rd comment to this question)
2. You must clone page from the PDF you want to merge, else, your application will print an error (self explanatory one) (found thanks to this slideshare which is very interesting for Zend_Pdf)
3. The static PDF must be a PDF <= 1.4 (mine was 1.6). Zend_Pdf can't parse PDF which version is > 1.4

I used this application to convert the static files I had in version 1.6 to 1.4.

Here's the rough code I have and work (I know it's not optimised, I'll do it later; but still, it can be useful)

$pdf2show = new Zend_Pdf();  // Initializing the merged PDF
$pdf1 = Zend_Pdf::parse($pdfContent, 1); // $pdfContent is the generated one, got the content...
$template = clone $pdf1->pages[0]; // cloning the page (a must do)
$page1 = new Zend_Pdf_Page($template); // Creating the first page of the merged PDF with the previous content
$pdf2show->pages[] = $page1; // Adding this page to the final PDF
$pdf2 = Zend_Pdf::load('urlToYourPDF.pdf'); // Loading the statif PDF
$template2 = clone $pdf2->pages[0]; // cloning the page (a must do)
$page2 = new Zend_Pdf_Page($template2); // Creating the second page of the merged PDF with the previous content
$pdf2show->pages[] = $page2; // Adding this page to the final PDF
sendToWebBrowser('title', $pdf2show->render());

sendToWebBrowser is a function sending the PDF content to browser with the title as... title. $pdf2show->render() produces the merged PDF content as a string.