在 WordPress 插件中的 Stripe customer.subscription.created 事件后不更新用户角色

Question

我正在创建一个 Wordpress 插件来处理我的网站的不同付费会员级别。 我已成功使用 Stripe 创建订阅，并在 Stripe 仪表板上收到“200 OK”响应。事件 customer.subscription.created 已成功触发。
如果用户选择 5 欧元/月的订阅，他将可以访问我网站上的一些特定帖子。我需要将他们的角色从“订阅者”更改为“自学者”才能实现这一点，但是当我检查数据库时，用户角色尚未更新，即使订阅已成功创建。 这是我的代码：

function stripe_webhook() {

    if(isset($_GET['webhook-listener']) && $_GET['webhook-listener'] == 'stripe') {

        if (is_user_logged_in()){ 

            $current_user = wp_get_current_user();

            require_once(plugin_dir_path(__FILE__) . 'stripe-library/init.php');

            global $italianglot_options;
            $italianglot_options = get_option('italianglot_settings');

            if(isset($italianglot_options['test_mode']) && $italianglot_options['test_mode']) { 
                $publishable = $italianglot_options['test_publishable_key'];
            } else {
                $publishable = $italianglot_options['live_publishable_key'];
            }

            if(isset($italianglot_options['test_mode']) && $italianglot_options['test_mode']) { 
                $secret_key = $italianglot_options['test_secret_key']; 
            } else {
                $secret_key = $italianglot_options['live_secret_key'];
            }

            if(isset($italianglot_options['test_mode']) && $italianglot_options['test_mode']) { 
                $price_selflearner_monthly = $italianglot_options['test_selflearner_monthly']; 
            } else {
                $price_selflearner_monthly = $italianglot_options['live_selflearner_monthly'];
            }

            if(isset($italianglot_options['test_mode']) && $italianglot_options['test_mode']) { 
                $price_selflearner_yearly = $italianglot_options['test_selflearner_yearly']; 
            } else {
                $price_selflearner_yearly = $italianglot_options['live_selflearner_yearly'];
            }

            Stripe::setApiKey($secret_key);

            if(isset($italianglot_options['test_mode']) && $italianglot_options['test_mode']) { 
                $endpoint_secret = $italianglot_options['test_endpoint_secret'];
            }else{
                $endpoint_secret = $italianglot_options['live_endpoint_secret'];
            }

            $body = @file_get_contents('php://input');
            $event_json = null;
            $event_json = json_decode($body);

            if(isset($event_json->id)) {
                try {

                    $event_id = $event_json->id;
                    $event = Stripe_Event::retrieve($event_id);
                    
                    switch ($event->type) {
                        case 'customer.subscription.trial_will_end':
                            $subscription = $event->data->object; // contains a \Stripe\Subscription
                            // Occurs three days before a subscription's trial period is scheduled to end, or when a trial is ended immediately (using trial_end=now).
                            // handleTrialWillEnd($subscription);
                            break;
                        case 'customer.subscription.created':
                            $subscription = $event->data->object; // contains a \Stripe\Subscription
                            // Occurs whenever a customer is signed up for a new plan.

                            $priceId = $subscription->items->data->price->id;
                        
                            if ($priceId == $price_selflearner_monthly || $priceId == $price_selflearner_yearly){
                                $current_user->set_role('self_learner');
                            }
                            
                           
                            break;
                        case 'customer.subscription.deleted':
                            $subscription = $event->data->object; // contains a \Stripe\Subscription
                            // Occurs whenever a customer's subscription ends.
                            
                            break;
                        case 'customer.subscription.updated':
                            $subscription = $event->data->object; // contains a \Stripe\Subscription
                            // Occurs whenever a subscription changes (e.g., switching from one plan to another, or changing the status from trial to active).
                            
                            break;
                        default:
                            // Unexpected event type
                            echo 'Received unknown event type';
                    }    

                } catch(\UnexpectedValueException $e) {
                // Invalid payload
                echo '⚠️  Webhook error while parsing basic request.';
                http_response_code(400);
                exit();
                }
            }    
        }    
    }
}

我什至不知道如何调试这段代码。我尝试检查将某些变量写入文件的值，但该文件始终为空。就好像 Case 'customer.subscription.cerated' 内的任何内容都没有被执行。

我用这段代码写在一个errors.txt 文件中：

$text = "PRICE ID: " . $priceId;
$file = plugin_dir_path( __FILE__ ) . '/errors.txt'; 
$open = fopen( $file, "a" ); 
$write = fputs( $open, $text); 
fclose( $open );

我希望有人能找出我的代码不起作用的原因。非常感谢！