Drupal Service for IP Blocking and Whitelisting

 Here's a simple PHP OOP-based class that you can use in a custom Drupal 10 module to implement IP blocking and whitelisting, along with a form to manage IPs.

 1. Define the PHP Class (IPManager.php)

Put this in your module's src/Service/IPManager.php.

PHP

namespace Drupal\your_module\Service;

use Symfony\Component\HttpFoundation\RequestStack;

class IPManager {

  protected $requestStack;

  // Define allowed and blocked IPs for simplicity.
  protected $whitelist = ['127.0.0.1']; // Add your trusted IPs here.
  protected $blacklist = ['192.168.1.10']; // Add blocked IPs here.

  public function __construct(RequestStack $request_stack) {
    $this->requestStack = $request_stack;
  }

  public function getClientIp() {
    return $this->requestStack->getCurrentRequest()->getClientIp();
  }

  public function isWhitelisted(): bool {
    return in_array($this->getClientIp(), $this->whitelist);
  }

  public function isBlacklisted(): bool {
    return in_array($this->getClientIp(), $this->blacklist);
  }

  public function checkAccess(): bool {
    if ($this->isWhitelisted()) {
      return true;
    }
    if ($this->isBlacklisted()) {
      return false;
    }
    return true; // Default allow
  }

}

2. Register the Service (your_module.services.yml)

YAML

services:
  your_module.ip_manager:
    class: Drupal\your_module\Service\IPManager
    arguments: ['@request_stack']

 3. Create a Simple Form to Manage IPs

Put this in src/Form/IPAccessForm.php:

PHP

namespace Drupal\your_module\Form;

use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;

class IPAccessForm extends FormBase {

  public function getFormId() {
    return 'ip_access_form';
  }

  public function buildForm(array $form, FormStateInterface $form_state) {
    $form['whitelist'] = [
      '#type' => 'textarea',
      '#title' => $this->t('Whitelisted IPs'),
      '#default_value' => '127.0.0.1',
      '#description' => $this->t('Enter one IP per line.'),
    ];

    $form['blacklist'] = [
      '#type' => 'textarea',
      '#title' => $this->t('Blacklisted IPs'),
      '#default_value' => '192.168.1.10',
      '#description' => $this->t('Enter one IP per line.'),
    ];

    $form['submit'] = [
      '#type' => 'submit',
      '#value' => $this->t('Save IPs'),
    ];

    return $form;
  }

  public function submitForm(array &$form, FormStateInterface $form_state) {
    // For demo purposes, just show a message. Save to config for real use.
    $whitelist = $form_state->getValue('whitelist');
    $blacklist = $form_state->getValue('blacklist');

    \Drupal::messenger()->addStatus($this->t('Saved IP settings.'));
  }
}



4. Route and Menu
your_module.routing.yml:
YAML

your_module.ip_access_form:
  path: '/admin/config/ip-access'
  defaults:
    _form: '\Drupal\your_module\Form\IPAccessForm'
    _title: 'IP Access Settings'
  requirements:
    _permission: 'administer site configuration'


5. Use the IP Check in a Controller or Event Subscriber
Example use in a controller:
PHP

$ipManager = \Drupal::service('your_module.ip_manager');
if (!$ipManager->checkAccess()) {
  throw new \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException();
}