<?php
$nodeurl = '#nodeurl/send';
 
$mediaurl = '#mediaurl';
 
$data = [
    'receiver'  => '#receiver',
    'msgtext'   => '#msgtext',
    'token'     => '#token',
    'mediaurl'  => $mediaurl, // delete this line if no media
];
 
$ch = curl_init();
curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/x-www-form-urlencoded']);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
curl_setopt($ch, CURLOPT_URL, $nodeurl);
curl_setopt($ch, CURLOPT_TIMEOUT, 30);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
$response = curl_exec($ch);
curl_close($ch);
 
echo $response; // output {success:true} or {success:false}
?>