How to clear a custom option via REST product update

Question

I am using product repository save() (rest POST /V1/products) to create/update products.

With a single select attribute I can add an option, but can't see any way to clear the attribute option if it's already set. Have tried sending 'null' and '' - doesn't add a new attribute, but also doesn't remove any existing ones either.

Here's a sample of the custom_options object within the product object.

 "custom_attributes": [
    {
      "attribute_code": "color",
      "value": "98"
    }

If I do something like this, the value remains in the database.

  "custom_attributes": [
    {
      "attribute_code": "color",
      "value": null
    }

Answer 1

It appears that null works - I had some custom code which was returning a false value.

Confirmed that data is being removed from catalog_product_eav_int/varchar for single/multi select attributes.