From d92e61e89f468c2db2fbd68b2f0d6b36c77f1065 Mon Sep 17 00:00:00 2001
From: Jeremy Kersten <jke@odoo.com>
Date: Fri, 25 Sep 2020 15:06:36 +0000
Subject: [FIX] tools.sql, website_*: increment counter with skip lock
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*blog, forum, slides

Based on https://github.com/odoo/odoo/pull/48552#discussion_r440061218 suggestion

Add a new method 'increment_skip_lock' in tools.sql to allow to easily
increment a specific field of 1 if the record is not locked.

The method return boolean if at least 1 record has been incremented.

closes odoo/odoo#58534

Signed-off-by: Jérémy Kersten (jke) <jke@openerp.com>
---
 odoo/tools/sql.py | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

(limited to 'odoo/tools/sql.py')

diff --git a/odoo/tools/sql.py b/odoo/tools/sql.py
index 69968f78de8..fc3d6f5524e 100644
--- a/odoo/tools/sql.py
+++ b/odoo/tools/sql.py
@@ -253,3 +253,27 @@ def reverse_order(order):
         direction = 'asc' if item[1:] == ['desc'] else 'desc'
         items.append('%s %s' % (item[0], direction))
     return ', '.join(items)
+
+
+def increment_field_skiplock(record, field):
+    """
+        Increment 'friendly' the [field] of the current [record](s)
+        If record is locked, we just skip the update.
+        It doesn't invalidate the cache since the update is not critical.
+
+        :rtype: bool - if field has been incremented or not
+    """
+    if not record:
+        return False
+
+    assert record._fields[field].type == 'integer'
+
+    cr = record._cr
+    query = """
+        UPDATE {table} SET {field} = {field} + 1 WHERE id IN (
+            SELECT id from {table} WHERE id in %(ids)s FOR UPDATE SKIP LOCKED
+        ) RETURNING id
+    """.format(table=record._table, field=field)
+    cr.execute(query, {'ids': tuple(record.ids)})
+
+    return bool(cr.fetchone())
-- 
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