From d10ee544b2619c7b23b5fa8f2be35a82a41a3459 Mon Sep 17 00:00:00 2001
From: Nurmatov Mamatisa <nurmatov.mamatisa@huawei.com>
Date: Fri, 4 Jun 2021 12:04:27 +0300
Subject: [PATCH] [DHCP] Fix cleanup_deleted_ports method

Assume that only one port is deleted within 24 hours, in method
cleanup_deleted_ports the port removes from deleted_ports but not
removes from deleted_ports_ts
In this fix ports older than 1 day will be dropped from
deleted_ports and deleted_ports_ts properly

Closes-Bug: #1930838
Change-Id: I1af32e72abb9f101f9729aa6d1354c33a95c98ee
(cherry picked from commit 383f209b502493ca6b059394e2644def754b2de1)
---
 neutron/agent/dhcp/agent.py                 | 5 +++--
 neutron/tests/unit/agent/dhcp/test_agent.py | 6 ++++++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/neutron/agent/dhcp/agent.py b/neutron/agent/dhcp/agent.py
index 4ed96537d6a..6b5a41ad735 100644
--- a/neutron/agent/dhcp/agent.py
+++ b/neutron/agent/dhcp/agent.py
@@ -1003,11 +1003,12 @@ class NetworkCache(object):
         "self._deleted_ports" and "self._deleted_ports_ts".
         """
         timestamp_min = timeutils.utcnow_ts() - DELETED_PORT_MAX_AGE
-        idx = None
-        for idx, (ts, port_id) in enumerate(self._deleted_ports_ts):
+        idx = 0
+        for (ts, port_id) in self._deleted_ports_ts:
             if ts > timestamp_min:
                 break
             self._deleted_ports.remove(port_id)
+            idx += 1
 
         if idx:
             self._deleted_ports_ts = self._deleted_ports_ts[idx:]
diff --git a/neutron/tests/unit/agent/dhcp/test_agent.py b/neutron/tests/unit/agent/dhcp/test_agent.py
index 494c20702fb..bf4b96624ba 100644
--- a/neutron/tests/unit/agent/dhcp/test_agent.py
+++ b/neutron/tests/unit/agent/dhcp/test_agent.py
@@ -1655,6 +1655,12 @@ class TestNetworkCache(base.BaseTestCase):
         nc = dhcp_agent.NetworkCache()
         nc.add_to_deleted_ports(fake_port1.id)
         utils.wait_until_true(lambda: nc._deleted_ports == set(), timeout=7)
+        self.assertEqual([], self.nc._deleted_ports_ts)
+
+        # check the second iteration is ok too
+        nc.add_to_deleted_ports(fake_port2.id)
+        utils.wait_until_true(lambda: nc._deleted_ports == set(), timeout=7)
+        self.assertEqual([], self.nc._deleted_ports_ts)
 
 
 class FakePort1(object):