Add Custom Field in Order and Quote Table To be Used in REST API

Question

Using UpgradeSchema, I've successfully added two fields to the table

quote

and

sales_order

The two fields are called

delivery_note_doc_due_date

and

remarks

My question is: how can I add the methods

getRemarks()
setRemarks()
getDeliveryNoteDocDueDate()
setDeliveryNoteDocDueDate()

inside the

Data\CartInterface 

and

Data\OrderInterface

modules so that I can use REST API to create an order?

Your help will be much appreciated!

LDR

Answer 1

You may create extension attributes:

etc/extension_attributes.xml

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Api/etc/extension_attributes.xsd">    
    <extension_attributes for="Magento\Sales\Api\Data\OrderInterface">
        <attribute code="remarks" type="string" />
        <attribute code="delivery_note_doc_due_date" type="string" />       
    </extension_attributes>
    <extension_attributes for="Magento\Quote\Api\Data\CartInterface">
        <attribute code="remarks" type="string" />
        <attribute code="delivery_note_doc_due_date" type="string" />       
    </extension_attributes>
</config>