PHP cURL - Send Data From www to Local IP

Question

I've been trying to use cURL to send data to a local IP. This IP is waiting to receive incoming data.

For this, I used the following code:

if(isset($_GET['post'])) {
    $data = array(
        'type' => 'direct',
        'packages' => []
    );

    $curl = curl_init('http://192.168.2.10:12800/api/install');
    curl_setopt($curl, CURLOPT_CUSTOMREQUEST, 'POST');
    curl_setopt($curl, CURLOPT_POSTFIELDS, json_encode($data));
    curl_setopt($curl, CURLOPT_FAILONERROR, true);
    curl_setopt($curl, CURLOPT_HTTPHEADER, array('Content-type: application/json'));
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);

    if (curl_errno($curl)) {
        $error_msg = curl_error($curl);
    }

    echo curl_exec($curl);

    if (isset($error_msg)) {
        echo $error_msg;
    } else {
        echo 'OK!';
    }
}

On localhost it works, but on a live website it doesn't.

I was thinking maybe it's not possible for non-localhost to communicate with localhost environments, but I'm unsure.

Is it possible to make my script send data to a local IP?

EDIT: Afterthought, do I have to switch to JavaScript to get this working?

Answer 1

In order to a remote server to communicate with your local infrastructure you would need to expose it via an external IP. So you need to:

1) set a routing of a port on your router (to passthru for example port 12800 to a particular IP in your local network - so for example if your external IP is 83.123.123.123 then router will passthru any traffic sent to 83.123.123.123:12800 to 192.168.2.10:12800. Usually such setting is called "routing" or "port forwarding" or "virtual servers" in router's settings.

2) learn your external ip. You can do it by going to for example: https://www.myexternalip.com/

3) if your IP is dynamic it may change from time to time. To avoid a problem you can set up a Dynamic DNS entry in one of the popular providers - like no-ip.com for example.