script.liquid

{% comment %}
  -- sort this option to the top
  {{ options.minutes_to_wait_before_removing_order_attributes__number_required }}
{% endcomment %}

{% assign attributes_to_remove = options.order_attributes_to_remove__array %}
{% assign remove_all_attributes = options.remove_all_order_attributes__boolean %}

{% unless remove_all_attributes or attributes_to_remove != blank %}
  {% error "Please choose either the 'Remove all order attributes' option, or enter one or more order attributes to remove" %}
  {% break %}
{% endunless %}

{% capture query %}
  query {
    order(id: {{ order.admin_graphql_api_id | json }}) {
      id
      customAttributes {
        key
        value
      }
    }
  }
{% endcapture %}

{% assign result = query | shopify %}

{% if event.preview %}
  {% capture result_json %}
    {
      "data": {
        "order": {
          "id": "gid://shopify/Order/1234567890",
          "customAttributes": [
            {
              "key": "preview",
              "value": "keep_this_one"
            },
            {
              "key": {{ attributes_to_remove.first | json }},
              "value": "remove_this_one"
            }
          ]
        }
      }
    }
  {% endcapture %}

  {% assign result = result_json | parse_json %}
{% endif %}

{% assign order_attributes = result.data.order.customAttributes %}

{% assign attributes_to_keep = array %}

{% unless remove_all_attributes %}
  {% for attribute in order_attributes %}
    {% unless attributes_to_remove contains attribute.key %}
      {% assign attributes_to_keep = attributes_to_keep | push: attribute %}
    {% endunless %}
  {% endfor %}
{% endunless %}

{% if attributes_to_keep == order_attributes %}
  {% log
    message: "No order attributes exist, or none matched the configured order attributes to remove",
    attributes_to_remove: attributes_to_remove,
    order_attributes: order_attributes
  %}
  {% break %}
{% endif %}

{% action "shopify" %}
  mutation {
    orderUpdate(
      input: {
        id: {{ order.admin_graphql_api_id | json }}
        customAttributes: {{ attributes_to_keep | graphql_arguments }}
    }) {
      order {
        id
        name
        customAttributes {
          key
          value
        }
      }
      userErrors {
        field
        message
      }
    }
  }
{% endaction %}