Is it possible to use multi curl in my php code? - php

Question

I am not sure how can or if I can use php multi curl function in the following situation:
I need to curl 3 different links while all of them are dependent to each other.
With the unique id obtained from the first link I will access the second link to retrieve another unique id which will be used in the 3rd link for the final result. See example below for better understanding:
$agent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36";
//open the session with the first link
$url1 = "http://first-link-example.com/execute";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url1);
curl_setopt($ch, CURLOPT_USERAGENT, $agent);
curl_setopt ($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt ($ch, CURLOPT_COOKIESESSION, TRUE);
curl_setopt ($ch, CURLOPT_COOKIEJAR, 'cookies.txt');
curl_setopt ($ch, CURLOPT_COOKIEFILE, 'cookies.txt');
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
$results = curl_exec($ch);
//get unique id from the link above
$unique1 = explode("string1", $results);
$unique1 = explode("string2", $unique1[1]);
//new request to access second link while preserving the session
$url2 = "http://second-link-example.com/execute?id=".$unique1[0];
curl_setopt($ch, CURLOPT_URL, $url2);
curl_setopt($ch, CURLOPT_USERAGENT, $agent);
curl_setopt ($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt ($ch, CURLOPT_COOKIESESSION, TRUE);
curl_setopt ($ch, CURLOPT_COOKIEJAR, 'cookies.txt');
curl_setopt ($ch, CURLOPT_COOKIEFILE, 'cookies.txt');
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
$results2 = curl_exec($ch);
//get the second unique id from $results2 page
$unique2 = explode("string1", $results2);
$unique2 = explode("string2", $unique2[1]);
//final request to retrieve the desired string while preserving the session
$url3 = "http://third-link-example.com/execute?id=".$unique2[0]."/response";
curl_setopt($ch, CURLOPT_URL, $url3);
curl_setopt($ch, CURLOPT_USERAGENT, $agent);
curl_setopt ($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt ($ch, CURLOPT_COOKIESESSION, TRUE);
curl_setopt ($ch, CURLOPT_COOKIEJAR, 'cookies.txt');
curl_setopt ($ch, CURLOPT_COOKIEFILE, 'cookies.txt');
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
$results3 = curl_exec($ch);
//get the desired string from $results3 page
$success = explode("string1", $results3);
$success = explode("string2", $success[1]);
echo $success[0];
curl_close($ch);
I did a lot of research on the web but couldn't find something appropriate and I wasn't able to understand how can I use multi curl in my situation or if it's possible.
Hopefully I made myself clear enough regarding what I'm looking for.
Thanks in advance to anyone who will be able to help me.

Answer 1

Short answer - NO.
Long answer - cURL multi handles are intended for asynchronous requests, i.e requests that don't block each other. In your case, each request blocks the one beforehand, as it is dependent on its response, so they must only be ran synchronously.