Get order shipping tax percent in Magento 2

Question

Since the order method getFullTaxInfo() is not available in Magento 2, how does one get the tax percent used on the order shipping amount for an order?

I see the item is in sales_order_tax_item table (where taxable_item_type = shipping), but I don't see any method in the Order or OrderInterface for fetching the tax details, except what is already in the Order table columns (tax amount, etc.). Weirdly enough this table also does not contain an order_id column, so there's no direct back-reference.

I know you can calculate the percentage manually but I think it's best to avoid it.

I see a promising method

\Magento\Sales\Model\ResourceModel\Order\Tax::getTaxItemsByOrderId($orderId)

but I have no idea how to properly use it.

Answer 1

I figured it out... Here's an example.

<?php
namespace Vendor\Module\Helper;

use \Magento\Framework\App\Helper\Context;
use \Magento\Sales\Api\Data\OrderInterface;
use \Magento\Sales\Model\ResourceModel\Order\Tax\Item;

class APIHelper extends \Magento\Framework\App\Helper\AbstractHelper
{
    /**
     * @var \Magento\Sales\Model\ResourceModel\Order\Tax\Item
     */
    protected $taxItem;

    public function __construct(
        Context $context,
        Item $taxItem
    ) {
        parent::__construct($context);
        $this->taxItem = $taxItem;
    }

    public function someMethod(OrderInterface $order)
    {
        $tax_items = $this->taxItem->getTaxItemsByOrderId($order->getId());
        var_dump($tax_items);
    }
}

Returns an array in format:

array (size=2)
  0 => 
    array (size=10)
      'tax_id' => string '9' (length=1)
      'tax_percent' => string '22.0000' (length=7)
      'item_id' => null
      'taxable_item_type' => string 'shipping' (length=8)
      'associated_item_id' => null
      'real_amount' => string '1.1000' (length=6)
      'real_base_amount' => string '1.1000' (length=6)
      'code' => string 'Slovenia (standard)' (length=19)
      'title' => string 'Slovenia (standard)' (length=19)
      'order_id' => string '22' (length=2)
  1 => 
    array (size=10)
      'tax_id' => string '9' (length=1)
      'tax_percent' => string '22.0000' (length=7)
      'item_id' => string '35' (length=2)
      'taxable_item_type' => string 'product' (length=7)
      'associated_item_id' => null
      'real_amount' => string '9.9000' (length=6)
      'real_base_amount' => string '9.9000' (length=6)
      'code' => string 'Slovenia (standard)' (length=19)
      'title' => string 'Slovenia (standard)' (length=19)
      'order_id' => string '22' (length=2)

So just iterate through and test if taxable_item_type equals to 'shipping':

    if (is_array($tax_items)) {
        foreach ($tax_items as $item) {
            if ($item['taxable_item_type'] === 'shipping') {
                // You got it
            }
        }
    }

I also had to recompile DI with setup:di:compile in CLI.