URL keeps on loading which is executed using php curl - php

Question

I am working on academic project for ecommerce which is about online book renting using PHP. I am making sure that user can only view rented book pdf file only after visiting site to do so I have use cloudfile.io which generate link for sharing file. I can use embed tag for adding file to my page but I don't want user to see file link so I use curl function to display file in my page but it keeps on loading.
<?php
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://cloudfil.es/0mU5B5e0eX3");
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
$data = curl_exec($ch);
echo $data;
curl_close($ch);
?>
I have tried to use headers for displaying pdf file this also doesn't work.

Answer 1

You need to clear anything already sent to the browser then send the correct headers so that the browser knows that a PDF is coming.
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,'https://cloudfil.es/0mU5B5e0eX3');
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
$data = curl_exec($ch);
curl_close($ch);
while (ob_get_level() !== 0) {ob_end_clean();}
header('Content-type:application/pdf');
header('Content-Disposition:attachment;filename="YourFileNameHere.pdf"');
echo $data;