Expanding Webservice Output For Orders

[SWN]

Hi, in order to integrate a third-party service in an older v1.5 PrestaShop, I need to add the 'unit_price_tax_incl' and 'unit_price_tax_excl' fields to the webservice output for orders, in the order_row section, just like it does in the latest version of prestashop.

 

From what I could tell, the only meaningful difference in this regard was that the fields weren't included in the webservice parameter definition in Order.php, but copying them over from latest version caused a weird error in which each field was just included in the output like this, lacking the actual value:

 

<unit_price_tax_incl notFilterable="true"/>

<unit_price_tax_excl notFilterable="true"/>

 

Does anyone know what is causing this, and what else needs to be done to get the fields included in the webservice output

 

Just updating PrestaShop is not an option.

Edited November 26, 2015 by SWN (see edit history)