brotherton-erpnext/erpnext/patches/v8_0/manufacturer_childtable_migrate.py

# Copyright (c) 2017, Frappe and Contributors
# License: GNU General Public License v3. See license.txt

from __future__ import unicode_literals
import frappe

def execute():

    # reading from json and writing it to mariadb
    # reload_doc needed here with information because new table introduced
    frappe.reload_doc('stock', 'doctype', 'item_manufacturer')
    # reload_doctype is a simpler concept of reload_doc
    frappe.reload_doctype('Item')

    item_manufacturers = frappe.get_all("Item", fields=["name", "manufacturer", "manufacturer_part_no"])
    for item in item_manufacturers:
        if item.manufacturer or item.manufacturer_part_no:
            item_doc = frappe.get_doc("Item", item.name)
            item_doc.append("manufacturers", {
                "manufacturer": item.manufacturer,
                "manufacturer_part_no": item.manufacturer_part_no
            })
            item_doc.flags.ignore_validate = True
            item_doc.flags.ignore_mandatory = True
            item_doc.save()