PHP hold request until finish - php

Question

I have an API written in PHP that sends 10 requests with CURL.
The problem is that when I send a HTTP request to the API, I get the response right away, although the server hasn't finished working( getting the response for all of the 10 requests).
I can't use ignore_user_abort() because I need to know exactly the time that the API finished.
How can I notify the connection "hey, wait for the script to finish working"?
Important note: if I use sleep() the connection holds.
Here's my code: gist

Answer 1

This is just a example to show how ob_start works.
echo "hello";
ob_start(); // output buffering starts here
echo "hello1";
//all curl requests
if(all curl requests completed)
{
ob_end_flush() ;
}
With no code to refer, I can only show implementation of ob_start. You have to change this code according to your requirement.
$handlers = [];
$mh = curl_multi_init();
ob_start(); // output buffering starts here
foreach($query->fetchAll() as $domain){
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'http://'.$domain['name']);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $DEFAULT_REQUEST_TIMEOUT);
curl_setopt($ch, CURLOPT_TIMEOUT, $DEFAULT_REQUEST_TIMEOUT);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_MAXREDIRS, 2);
curl_multi_add_handle($mh, $ch);
$handlers[] = ['ch'=>$ch, 'domain_id'=>$domain['domain_id']];
echo $domain['name'];
}
// Execute the handles
$active = null;
do {
$mrc = curl_multi_exec($mh, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);
while ($active && $mrc == CURLM_OK) {
// Wait for activity on any curl-connection
if (curl_multi_select($mh) == -1) {
usleep(1);
}
// Continue to exec until curl is ready to
// give us more data
do {
$mrc = curl_multi_exec($mh, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);
}
// Extract the content
$values = [];
foreach($handlers as $key => $handle){
// Check for errors
echo $key.'. result: ';
$curlError = curl_error($handle['ch']);
if($curlError == ""){
$res = curl_multi_getcontent($handle['ch']);
echo 'done';
}
else {
echo "Curl error on handle $key: $curlError".' <br />';
}
// Remove and close the handle
curl_multi_remove_handle($mh, $handle['ch']);
curl_close($handle['ch']);
}
// Clean up the curl_multi handle
curl_multi_close($mh);
ob_end_flush() ; // output flushed here
Source - http://php.net/manual/en/function.ob-start.php

Answer 2

I use this code for my website
ob_start("unique_identifier");
// your header script
// your page script
// your footer script
ob_end_flush("unique_identifier");
ob_end_clean("unique_identifier");
I use "unique_identifier" because inside my script also exists another
ob_start()