Merge two pdfs with Ilovepdf and dompdf - php

Question

I have a code to convert an html text into pdf and another to merge this pdf with a pdf that the user uploads, but I can't merge the two together, it downloads the converted pdf and not the merged one.
When I put just to merge with two files that the user uploads it works.
My code:
$dompdf = new Dompdf();
$dompdf->loadHtml('hello world');
// (Optional) Setup the paper size and orientation
$dompdf->setPaper('A4', 'landscape');
// Render the HTML as PDF
$dompdf->render();
// Output the generated PDF to Browser
$arquivo = $dompdf->stream();
$ilovepdf = new Ilovepdf('iLovePdfKey', 'iLovePdfKey');
// Create a new task
$myTaskMerge = $ilovepdf->newTask('merge');
// Add files to task for upload
$arquivo = $this->convertHello();
$file1 = $myTaskMerge->addFile('path to the file that the user upload');
$file2 = $myTaskMerge->addFile($arquivo);
// Execute the task
$myTaskMerge->execute();
// Download the package files
$myTaskMerge->download();

Answer 1

$dompdf->stream() sends the rendered PDF to the browser. As such you can't access the generated PDF that way. You have to capture the output and save to a file.
Based on your sample code, something like this:
$dompdf = new Dompdf();
$dompdf->loadHtml('hello world');
$dompdf->render();
$arquivo = $dompdf->output();
$tmp = tempnam(sys_get_temp_dir(), "pdf")
file_put_contents($tmp, $arquivo);
$ilovepdf = new Ilovepdf('iLovePdfKey', 'iLovePdfKey');
$myTaskMerge = $ilovepdf->newTask('merge');
$file1 = $myTaskMerge->addFile('path to the file that the user upload');
$file2 = $myTaskMerge->addFile($tmp);
$myTaskMerge->execute();
unset($tmp);
$myTaskMerge->download();