openstack
/
charm-interface-mysql-router
Code Issues Proposed changes

Wipe 'prefixes' key on relation departed 

The prefix key is used to track requests that have been proxied
to mysql-innodb-cluster. When a request for a username and password
is made the prefix used is stored locally in a list *1. This list
of prefixes is also used to check that requests are complete *2
However the list presists after a relation is removed. If
the relation is added back the charm reads the old list of
prefixes and will not raise the db-router.available flag
because it thinks there is an oustanding request *3.

*1 https://opendev.org/openstack/charm-interface-mysql-router/src/branch/master/requires.py#L61
*2 https://opendev.org/openstack/charm-interface-mysql-router/src/branch/master/requires.py#L151
*3 https://opendev.org/openstack/charm-interface-mysql-router/src/branch/master/requires.py#L20

Closes-Bug: #1972883
Change-Id: I8ce022a44db37ab83c03442c5f97a843521286d2
This commit is contained in:
Liam Young 2022-05-12 12:11:05 +00:00
parent 21586be61f
commit 77dc778e60
2 changed files with 17 additions and 0 deletions
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5
requires.py
View File

@ -41,12 +41,17 @@ class MySQLRouterRequires(reactive.RelationBase):
self.remove_state('{relation_name}.proxy.available')
self.remove_state('{relation_name}.available.ssl')
# Check if this is the last unit
last_unit = True
for conversation in self.conversations():
for rel_id in conversation.relation_ids:
if len(hookenv.related_units(rel_id)) > 0:
# This is not the last unit so reevaluate state
self.joined()
self.changed()
last_unit = False
if last_unit:
# Bug #1972883
self.set_local('prefixes', [])
def configure_db_router(self, username, hostname, prefix):
"""

12
unit_tests/test_requires.py
View File

@ -271,3 +271,15 @@ class TestMySQLRouterRequires(unittest.TestCase):
_second = "secondprefix"
self.mysql_router.set_prefix(_second)
self.set_local.assert_called_once_with("prefixes", [_prefix, _second])
@mock.patch.object(requires.hookenv, 'related_units')
def test_ly_departed(self, related_units):
self._local_data = {"prefixes": ["myprefix"]}
related_units.return_value = ['unit/1']
self.mysql_router.departed()
self.assertFalse(self.set_local.called)
related_units.return_value = []
self.mysql_router.departed()
self.set_local.assert_called_once_with("prefixes", [])