How best to check if a user is from China and hide content?

Question

To speed up my website in China I thought of hiding blocked services from Chinese users and wrote this and put it in functions.php

$isInChina = false; 
$ip = $_SERVER['REMOTE_ADDR']; // This will contain the ip of the request 
// This service tells me where the IP address is from and gives me more data than I need. 
$userData = json_decode(file_get_contents("http://www.geoplugin.net/json.gp?ip=".$ip)); 
if (is_Null($userData) || empty($userData) || $userData->geoplugin_countryCode == "CN")
{ 
    $isInChina = true; // Count no data as in China maybe to be paranoid. 
}

Shouldn't I store the result in some session level variable?

Answer 1

Yes, storing the result in a session-level variable is a good idea for performance optimization. By doing so, you avoid making repeated requests to the external geolocation service every time a page is loaded, which can slow down your website and increase the load on that service.

Here’s how you can modify your code to store the result in a session variable:

session_start(); // Start the session at the beginning of your script

if (!isset($_SESSION['isInChina'])) {
    $isInChina = false; 
    $ip = $_SERVER['REMOTE_ADDR']; // Get the user's IP address
    $userData = @json_decode(file_get_contents("http://www.geoplugin.net/json.gp?ip=".$ip)); 
    
    if (is_null($userData) || empty($userData) || $userData->geoplugin_countryCode == "CN") {
        $isInChina = true; // If no data or if the country code is China, assume user is in China
    }
    
    $_SESSION['isInChina'] = $isInChina; // Store the result in session
} else {
    $isInChina = $_SESSION['isInChina']; // Retrieve the result from session
}

Benefits:

• Performance: Reduces the number of external requests by storing the result in the session, which speeds up subsequent page loads.

• Efficiency: Reduces the load on the geolocation service by avoiding unnecessary calls.

Answer 2

I'd recommend using something like this https://www.geoplugin.com/ and write an if statement for a either a display none or noscript. If you're looking for a good code base to start with I'd take a look at this answer. https://stackoverflow.com/a/13600004/3175165