[SOLVED] PHP cURL required only to send and not wait for response

Issue

I need a PHP cURL configuration so that my script is able to send requests and ignore the answers sent by the API.

curl_setopt($ch,CURLOPT_URL,$url);
curl_setopt($ch,CURLOPT_POST,count($fields));
curl_setopt($ch,CURLOPT_POSTFIELDS,$fields_string);
// curl_setopt($ch, CURLOPT_RETURNTRANSFER, false);
//curl_setopt($ch, CURLOPT_TIMEOUT_MS, 100);
$result = curl_exec($ch);
echo $result;
curl_close ($ch);

I tried adding: // curl_setopt($ch, CURLOPT_RETURNTRANSFER, false); //curl_setopt($ch, CURLOPT_TIMEOUT_MS, 100);

But its not working properly and the API webserver is not receiving the requests.

The reason for this is I am sending large amount of requests to the API therefore my script is very slow because it waits for each and every request.

Any help is appreciated.

Solution

Sender file example ./ajax/sender.php

Script sending POST -> it makes full request to host, but it doesn't wait on answer from server : CURLOPT_HEADER(0) we dont needs headers from server) and CURLOPT_RETURNTRANSFER (false) we don't needs data from server.CURLOPT_TIMEOUT - Extra procteted : We waiting after sent only 1ms on respond server, this is extra quaranty to not wait any more ms if server keep us. ### NOTE ### HTTP1.1 has one package max 16kb. HTTP2 has 36kb one pacakge. If POST are more biggest, server will be send with many packages in series = $SIZE%16kb

    $url = 'https://127.0.0.1/ajax/received.php';
    $curl = curl_init();                
    $post['test'] = 'examples daata'; // our data todo in received
    curl_setopt($curl, CURLOPT_URL, $url);
    curl_setopt ($curl, CURLOPT_POST, TRUE);
    curl_setopt ($curl, CURLOPT_POSTFIELDS, $post); 
    
    curl_setopt($curl, CURLOPT_USERAGENT, 'api');

    //curl_setopt($curl, CURLOPT_TIMEOUT, 1); //if your connect is longer than 1s it lose data in POST better is finish script in recevie
    curl_setopt($curl, CURLOPT_HEADER, 0);
    curl_setopt($curl,  CURLOPT_RETURNTRANSFER, false);
    curl_setopt($curl, CURLOPT_FORBID_REUSE, true);
    curl_setopt($curl, CURLOPT_CONNECTTIMEOUT, 1);
    curl_setopt($curl, CURLOPT_DNS_CACHE_TIMEOUT, 100); 
    
    curl_setopt($curl, CURLOPT_FRESH_CONNECT, true);
    
    curl_exec($curl);   
    
    curl_close($curl);  

Received file example ./ajax/received.php

    ignore_user_abort(true); //if connect is close, we continue php script in background up to script will be end
    
            header("Connection: close\r\n"); 
            header("Content-Encoding: none\r\n"); 
            header("Content-Length: 1"); 
    ### we just close connect above if webbrowser, or request waiting on answer ( we know we set CURLOP to not wait) ###
ob_end_clean(); //just flush all content if exists to request. If server still waiting on answer.
            //HERE all script doing in background: Example
            $this->db->query('UPDATE new_hook_memory SET new=new+1 WHERE id=1');
 

EDIT 2019 if you using fastcgi just finish fastcgi and browser close connection but script still will be working up to end.

How finish script: PHP mod_fcgi with fastcgi_finish_request();

For Apache2:

ob_end_flush();
flush();

For php-fpm

fastcgi_finish_request(); $this->db->query('UPDATE new_hook_memory SET new=new+1 WHERE id=1');

Old version:

Answered By - Kamil Dąbrowski

Answer Checked By - Willingham (WPSolving Volunteer)