PHP Apple internal purchase callback processing

 public function notify(){

        $response = file_get_contents( "php://input");
        
        $result = json_decode($response,true);
        if($result['password']!=' Secret key '){// Judgement key 
            $this->error("password error","",500);
        }
        // product ID
        $product_id = $result['auto_renew_product_id'];
        // Get the original transaction ID
        foreach ($result['unified_receipt']['pending_renewal_info'] as $kk => $vv){
            if($vv['product_id'] == $product_id){
                $original_transaction_id = $vv['original_transaction_id'];
            }
        }
        if(!$original_transaction_id){
            $this->error("original_transaction_id error","",500);
        }
        // Current transaction information 
        $latest_receipt_info = $result['unified_receipt']['latest_receipt_info'][0];
        // Expiration time 
        $ex