Improve performance for warehouse tree (#15207)

* Fix conflicts

* Modify query structure

* Remove whitespaces

erpnext/stock/doctype/warehouse/warehouse.py

@@ -139,7 +139,7 @@ class Warehouse(NestedSet):
 
 @frappe.whitelist()
 def get_children(doctype, parent=None, company=None, is_root=False):
-	from erpnext.stock.utils import get_stock_value_on
+	from erpnext.stock.utils import get_stock_value_from_bin
 
 	if is_root:
 		parent = ""
@@ -154,7 +154,7 @@ def get_children(doctype, parent=None, company=None, is_root=False):
 
 	# return warehouses
 	for wh in warehouses:
-		wh["balance"] = get_stock_value_on(warehouse=wh.value)
+		wh["balance"] = get_stock_value_from_bin(warehouse=wh.value)
 	return warehouses
 
 @frappe.whitelist()

erpnext/stock/utils.py

@@ -9,6 +9,30 @@ from frappe.utils import flt, cstr, nowdate, nowtime
 
 class InvalidWarehouseCompany(frappe.ValidationError): pass
 
+def get_stock_value_from_bin(warehouse=None, item_code=None):
+	values = {}
+	conditions = ""
+	if warehouse:
+		conditions += """ and warehouse in (
+						select w2.name from `tabWarehouse` w1
+						join `tabWarehouse` w2 on
+						w1.name = %(warehouse)s
+						and w2.lft between w1.lft and w1.rgt
+						) """
+
+		values['warehouse'] = warehouse
+
+	if item_code:
+		conditions += " and item_code = %(item_code)s"
+
+		values['item_code'] = item_code
+
+	query = "select sum(stock_value) from `tabBin` where 1 = 1 %s" % conditions
+
+	stock_value = frappe.db.sql(query, values)
+
+	return stock_value
+
 def get_stock_value_on(warehouse=None, posting_date=None, item_code=None):
 	if not posting_date: posting_date = nowdate()
 
@@ -219,4 +243,3 @@ def validate_warehouse_company(warehouse, company):
 def is_group_warehouse(warehouse):
 	if frappe.db.get_value("Warehouse", warehouse, "is_group"):
 		frappe.throw(_("Group node warehouse is not allowed to select for transactions"))
-