fix: DB update child items, remove redundancy, fix perf

- Move `get_boms_in_bottom_up_order` in bom update tool’s file
- Remove repeated rm cost update from `update_cost`. `calculate_cost` handles RM cost update
- db_update children in `calculate_cost` optionally
- Don’t call `update_exploded_items` and regenerate exploded items in `update_cost`. They will stay the same (except cost)

erpnext/manufacturing/doctype/bom/bom.py

@@ -3,9 +3,9 @@
 
 import functools
 import re
-from collections import defaultdict, deque
+from collections import deque
 from operator import itemgetter
-from typing import List, Optional
+from typing import List
 
 import frappe
 from frappe import _
@@ -373,35 +373,9 @@ class BOM(WebsiteGenerator):
 
 		existing_bom_cost = self.total_cost
 
-		for d in self.get("items"):
-			if not d.item_code:
-				continue
-
-			rate = self.get_rm_rate(
-				{
-					"company": self.company,
-					"item_code": d.item_code,
-					"bom_no": d.bom_no,
-					"qty": d.qty,
-					"uom": d.uom,
-					"stock_uom": d.stock_uom,
-					"conversion_factor": d.conversion_factor,
-					"sourced_by_supplier": d.sourced_by_supplier,
-				}
-			)
-
-			if rate:
-				d.rate = rate
-			d.amount = flt(d.rate) * flt(d.qty)
-			d.base_rate = flt(d.rate) * flt(self.conversion_rate)
-			d.base_amount = flt(d.amount) * flt(self.conversion_rate)
-
-			if save:
-				d.db_update()
-
 		if self.docstatus == 1:
 			self.flags.ignore_validate_update_after_submit = True
-			self.calculate_cost(update_hour_rate)
+			self.calculate_cost(save_updates=save, update_hour_rate=update_hour_rate)
 		if save:
 			self.db_update()
 
@@ -603,11 +577,11 @@ class BOM(WebsiteGenerator):
 		bom_list.reverse()
 		return bom_list
 
-	def calculate_cost(self, update_hour_rate=False):
+	def calculate_cost(self, save_update=False, update_hour_rate=False):
 		"""Calculate bom totals"""
 		self.calculate_op_cost(update_hour_rate)
-		self.calculate_rm_cost()
+		self.calculate_rm_cost(save=save_update)
-		self.calculate_sm_cost()
+		self.calculate_sm_cost(save=save_update)
 		self.total_cost = self.operating_cost + self.raw_material_cost - self.scrap_material_cost
 		self.base_total_cost = (
 			self.base_operating_cost + self.base_raw_material_cost - self.base_scrap_material_cost
@@ -649,7 +623,7 @@ class BOM(WebsiteGenerator):
 		if update_hour_rate:
 			row.db_update()
 
-	def calculate_rm_cost(self):
+	def calculate_rm_cost(self, save=False):
 		"""Fetch RM rate as per today's valuation rate and calculate totals"""
 		total_rm_cost = 0
 		base_total_rm_cost = 0
@@ -664,11 +638,13 @@ class BOM(WebsiteGenerator):
 
 			total_rm_cost += d.amount
 			base_total_rm_cost += d.base_amount
+			if save:
+				d.db_update()
 
 		self.raw_material_cost = total_rm_cost
 		self.base_raw_material_cost = base_total_rm_cost
 
-	def calculate_sm_cost(self):
+	def calculate_sm_cost(self, save=False):
 		"""Fetch RM rate as per today's valuation rate and calculate totals"""
 		total_sm_cost = 0
 		base_total_sm_cost = 0
@@ -683,6 +659,8 @@ class BOM(WebsiteGenerator):
 			)
 			total_sm_cost += d.amount
 			base_total_sm_cost += d.base_amount
+			if save:
+				d.db_update()
 
 		self.scrap_material_cost = total_sm_cost
 		self.base_scrap_material_cost = base_total_sm_cost
@@ -1120,81 +1098,6 @@ def get_children(doctype, parent=None, is_root=False, **filters):
 		return bom_items
 
 
-def get_boms_in_bottom_up_order(bom_no: Optional[str] = None) -> List:
-	def _generate_child_parent_map():
-		bom = frappe.qb.DocType("BOM")
-		bom_item = frappe.qb.DocType("BOM Item")
-
-		bom_parents = (
-			frappe.qb.from_(bom_item)
-			.join(bom)
-			.on(bom_item.parent == bom.name)
-			.select(bom_item.bom_no, bom_item.parent)
-			.where(
-				(bom_item.bom_no.isnotnull())
-				& (bom_item.bom_no != "")
-				& (bom.docstatus == 1)
-				& (bom.is_active == 1)
-				& (bom_item.parenttype == "BOM")
-			)
-		).run(as_dict=True)
-
-		child_parent_map = defaultdict(list)
-		for bom in bom_parents:
-			child_parent_map[bom.bom_no].append(bom.parent)
-
-		return child_parent_map
-
-	def _get_flat_parent_map(leaf, child_parent_map):
-		parents_list = []
-
-		def _get_parents(node, parents_list):
-			"Returns updated ancestors list."
-			first_parents = child_parent_map.get(node)  # immediate parents of node
-			if not first_parents:  # top most node
-				return parents_list
-
-			parents_list.extend(first_parents)
-			parents_list = list(dict.fromkeys(parents_list).keys())  # remove duplicates
-
-			for nth_node in first_parents:
-				# recursively find parents
-				parents_list = _get_parents(nth_node, parents_list)
-
-			return parents_list
-
-		parents_list = _get_parents(leaf, parents_list)
-		return parents_list
-
-	def _get_leaf_boms():
-		return frappe.db.sql_list(
-			"""select name from `tabBOM` bom
-			where docstatus=1 and is_active=1
-				and not exists(select bom_no from `tabBOM Item`
-					where parent=bom.name and ifnull(bom_no, '')!='')"""
-		)
-
-	bom_list = []
-	if bom_no:
-		bom_list.append(bom_no)
-	else:
-		bom_list = _get_leaf_boms()
-
-	child_parent_map = _generate_child_parent_map()
-
-	for leaf_bom in bom_list:
-		# generate list recursively bottom to top
-		parent_list = _get_flat_parent_map(leaf_bom, child_parent_map)
-
-		if not parent_list:
-			continue
-
-		bom_list.extend(parent_list)
-		bom_list = list(dict.fromkeys(bom_list).keys())  # remove duplicates
-
-	return bom_list
-
-
 def add_additional_cost(stock_entry, work_order):
 	# Add non stock items cost in the additional cost
 	stock_entry.additional_costs = []

erpnext/manufacturing/doctype/bom_update_tool/bom_update_tool.py

@@ -2,7 +2,8 @@
 # For license information, please see license.txt
 
 import json
-from typing import TYPE_CHECKING, Dict, Optional, Union
+from collections import defaultdict
+from typing import TYPE_CHECKING, Dict, List, Optional, Union
 
 from typing_extensions import Literal
 
@@ -12,8 +13,6 @@ if TYPE_CHECKING:
 import frappe
 from frappe.model.document import Document
 
-from erpnext.manufacturing.doctype.bom.bom import get_boms_in_bottom_up_order
-
 
 class BOMUpdateTool(Document):
 	pass
@@ -49,7 +48,10 @@ def update_cost() -> None:
 	"""Updates Cost for all BOMs from bottom to top."""
 	bom_list = get_boms_in_bottom_up_order()
 	for bom in bom_list:
-		frappe.get_doc("BOM", bom).update_cost(update_parent=False, from_child_bom=True)
+		bom_doc = frappe.get_doc("BOM", bom)
+		bom_doc.calculate_cost(save_updates=True, update_hour_rate=True)
+		# bom_doc.update_exploded_items(save=True) #TODO: edit exploded items rate
+		bom_doc.db_update()
 
 
 def create_bom_update_log(
@@ -69,3 +71,90 @@ def create_bom_update_log(
 			"update_type": update_type,
 		}
 	).submit()
+
+
+def get_boms_in_bottom_up_order(bom_no: Optional[str] = None) -> List:
+	"""
+	Eg: Main BOM
+	        |- Sub BOM 1
+	                |- Leaf BOM 1
+	        |- Sub BOM 2
+	                |- Leaf BOM 2
+	Result: [Leaf BOM 1, Leaf BOM 2, Sub BOM 1, Sub BOM 2, Main BOM]
+	"""
+	leaf_boms = []
+	if bom_no:
+		leaf_boms.append(bom_no)
+	else:
+		leaf_boms = _get_leaf_boms()
+
+	child_parent_map = _generate_child_parent_map()
+	bom_list = leaf_boms.copy()
+
+	for leaf_bom in leaf_boms:
+		parent_list = _get_flat_parent_map(leaf_bom, child_parent_map)
+
+		if not parent_list:
+			continue
+
+		bom_list.extend(parent_list)
+		bom_list = list(dict.fromkeys(bom_list).keys())  # remove duplicates
+
+	return bom_list
+
+
+def _generate_child_parent_map():
+	bom = frappe.qb.DocType("BOM")
+	bom_item = frappe.qb.DocType("BOM Item")
+
+	bom_parents = (
+		frappe.qb.from_(bom_item)
+		.join(bom)
+		.on(bom_item.parent == bom.name)
+		.select(bom_item.bom_no, bom_item.parent)
+		.where(
+			(bom_item.bom_no.isnotnull())
+			& (bom_item.bom_no != "")
+			& (bom.docstatus == 1)
+			& (bom.is_active == 1)
+			& (bom_item.parenttype == "BOM")
+		)
+	).run(as_dict=True)
+
+	child_parent_map = defaultdict(list)
+	for bom in bom_parents:
+		child_parent_map[bom.bom_no].append(bom.parent)
+
+	return child_parent_map
+
+
+def _get_flat_parent_map(leaf, child_parent_map):
+	"Get ancestors at all levels of a leaf BOM."
+	parents_list = []
+
+	def _get_parents(node, parents_list):
+		"Returns recursively updated ancestors list."
+		first_parents = child_parent_map.get(node)  # immediate parents of node
+		if not first_parents:  # top most node
+			return parents_list
+
+		parents_list.extend(first_parents)
+		parents_list = list(dict.fromkeys(parents_list).keys())  # remove duplicates
+
+		for nth_node in first_parents:
+			# recursively find parents
+			parents_list = _get_parents(nth_node, parents_list)
+
+		return parents_list
+
+	parents_list = _get_parents(leaf, parents_list)
+	return parents_list
+
+
+def _get_leaf_boms():
+	return frappe.db.sql_list(
+		"""select name from `tabBOM` bom
+		where docstatus=1 and is_active=1
+			and not exists(select bom_no from `tabBOM Item`
+				where parent=bom.name and ifnull(bom_no, '')!='')"""
+	)