[FIX] stock, purchase_stock: read virtual_available in batch

Performance improvement for missing products computation.
- Call _prepare_sellers only once
- _compute_quantities works in batch for product with the same
context. Use this advantage to speedup the computation of virtual
available for each warehouse and delivery date.

2 files changed, 19 insertions, 9 deletions

diff --git a/addons/purchase_stock/models/stock_rule.py b/addons/purchase_stock/models/stock_rule.py
index 51c68706d31..f6a14616e50 100644
--- a/addons/purchase_stock/models/stock_rule.py
+++ b/addons/purchase_stock/models/stock_rule.py
@@ -149,10 +149,11 @@ class StockRule(models.Model):
         """
         delay, delay_description = super()._get_lead_days(product)
         buy_rule = self.filtered(lambda r: r.action == 'buy')
-        if not buy_rule or not product._prepare_sellers():
+        seller = product._prepare_sellers()
+        if not buy_rule or not seller:
             return delay, delay_description
         buy_rule.ensure_one()
-        supplier_delay = product._prepare_sellers()[0].delay
+        supplier_delay = seller[0].delay
         if supplier_delay:
             delay_description += '<tr><td>%s</td><td class="text-right">+ %d %s</td></tr>' % (_('Vendor Lead Time'), supplier_delay, _('day(s)'))
         security_delay = buy_rule.picking_type_id.company_id.po_lead
diff --git a/addons/stock/models/stock_orderpoint.py b/addons/stock/models/stock_orderpoint.py
index d45d3d72d24..c2b61ea4771 100644
--- a/addons/stock/models/stock_orderpoint.py
+++ b/addons/stock/models/stock_orderpoint.py
@@ -319,19 +319,28 @@ class StockWarehouseOrderpoint(models.Model):
         # Recompute the forecasted quantity for missing product today but at this time
         # with their real lead days.
         key_to_remove = []
+
+        # group product by lead_days and warehouse in order to read virtual_available
+        # in batch
+        pwh_per_day = defaultdict(list)
         for (product, warehouse), quantity in to_refill.items():
             product = self.env['product.product'].browse(product)
             warehouse = self.env['stock.warehouse'].browse(warehouse)
             rules = product._get_rules_from_location(warehouse.lot_stock_id)
             lead_days = rules._get_lead_days(product)[0]
-            virtual_available = product.with_context(
+            pwh_per_day[(lead_days, warehouse)].append(product.id)
+        for (days, warehouse), p_ids in pwh_per_day.items():
+            products = self.env['product.product'].browse(p_ids)
+            qties = products.with_context(
                 warehouse=warehouse.id,
-                to_date=fields.datetime.now() + relativedelta.relativedelta(days=lead_days)
-            ).virtual_available
-            if float_compare(virtual_available, 0, precision_rounding=product.uom_id.rounding) >= 0:
-                key_to_remove.append((product.id, warehouse.id))
-            else:
-                to_refill[(product.id, warehouse.id)] = virtual_available
+                to_date=fields.datetime.now() + relativedelta.relativedelta(days=days)
+            ).read(['virtual_available'])
+            for qty in qties:
+                if float_compare(qty['virtual_available'], 0, precision_rounding=product.uom_id.rounding) >= 0:
+                    key_to_remove.append((qty['id'], warehouse.id))
+                else:
+                    to_refill[(qty['id'], warehouse.id)] = qty['virtual_available']
+
         for key in key_to_remove:
             del to_refill[key]
         if not to_refill: