Is this possible?
I deeply modified my woocommerce website to allow interaction with my company webservices.
Actually I add products programmatically reading values from a webservice and adding later custom detailed fields.
In particular my products are tyres and wheels.
Here a screenshot of how I do that:

foreach($product->children() as $field)
	{
		if($field->getName() != 'Value' && $field->getName() != 'Description' && $field->getName() != 'ProductImage')
		{	
			$fieldName = (string)$field->getName();
			add_custom_product_attributes($product_attributes, $fieldsArray[$fieldName]->caption, $fieldsArray[$fieldName]->tab, (string)$field); 
		}
	}
update_post_meta( $post_id, '_product_attributes', $product_attributes); // very important for custom fields

function add_custom_product_attributes(&$product_attributes, $name, $value, $tab='Main informations', $position = 1, $is_visible = 1, $is_variable = 1, $is_taxonomy = 0)
{
	$product_attributes[$name] = array(
        //Make sure the 'name' is same as you have the attribute
        'name' => htmlspecialchars(stripslashes($name)),
        'value' => $value,
        'position' => $position,
        'is_visible' => $is_visible,
        'is_variation' => $is_variable,
        'is_taxonomy' => $is_taxonomy,
		'tab' => $tab
    );
}

I’d like to filter for these ‘product_attributes’. Is there a way? if I try to add the related meta field I can only the meta product_attributes even if it’s an array. I need to access puntually to these array fields.

I hope you can help me.

Thanks in advance,
Fabio