From b173169528cba8f33fa0b3b397fa1e474f5653a1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89ric=20Falconnier?= <eric@zentral.com>
Date: Sun, 8 Sep 2024 15:35:55 +0200
Subject: [PATCH] Use table lock on santa_targetcounter to avoid deadlocks

---
 zentral/contrib/santa/utils.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/zentral/contrib/santa/utils.py b/zentral/contrib/santa/utils.py
index 9762c37bda..083a866a3d 100644
--- a/zentral/contrib/santa/utils.py
+++ b/zentral/contrib/santa/utils.py
@@ -150,6 +150,9 @@ def update_or_create_targets(configuration, targets):
         ') select * from observed_targets;'
     )
     with connection.cursor() as cursor:
+        # To avoid deadlocks between transactions updating the same counters we need to lock the table.
+        # TODO find a better way.
+        cursor.execute("LOCK TABLE ONLY santa_targetcounter IN SHARE ROW EXCLUSIVE MODE")
         result = psycopg2.extras.execute_values(
             cursor, query,
             ((target_type.value, target_identifier, configuration.id,