integration tests fail in the CI with mysql-k8s unit in error

[NohaIhab]

Bug Description

integration test test_add_relational_db_with_relation_expect_active fails with mysql-k8s unit in error with hook failed: "config-changed", observed in the CI of PR #223

To Reproduce

run the CI in PR #223

Environment

mysql-k8s 8.0/stable

Relevant Log Output

unit-mysql-k8s-0: 13:10:22 ERROR unit.mysql-k8s/0.juju-log Uncaught exception while in charm code:
Traceback (most recent call last):
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/./src/charm.py", line 786, in <module>
    main(MySQLOperatorCharm)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/main.py", line 436, in main
    _emit_charm_event(charm, dispatcher.event_name)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/main.py", line 144, in _emit_charm_event
    event_to_emit.emit(*args, **kwargs)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/framework.py", line 351, in emit
    framework._emit(event)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/framework.py", line 853, in _emit
    self._reemit(event_path)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/framework.py", line 942, in _reemit
    custom_handler(event)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/./src/charm.py", line 412, in _on_config_changed
    if not self._mysql.is_mysqld_running():
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/src/mysql_k8s_helpers.py", line 564, in is_mysqld_running
    return self.container.exists(MYSQLD_SOCK_FILE)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/model.py", line 2547, in exists
    self._pebble.list_files(str(path), itself=True)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/pebble.py", line 2219, in list_files
    resp = self._request('GET', '/v1/files', query)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/pebble.py", line 1655, in _request
    response = self._request_raw(method, path, query, headers, data)
  File "/var/lib/juju/agents/unit-mysql-k8s-0/charm/venv/ops/pebble.py", line 1704, in _request_raw
    raise ConnectionError(
ops.pebble.ConnectionError: Could not connect to Pebble: socket not found at '/charm/containers/mysql/pebble.socket' (container restarted?)
unit-mysql-k8s-0: 13:10:23 ERROR juju.worker.uniter.operation hook "config-changed" (via hook dispatching script: dispatch) failed: exit status 1

Additional Context

No response

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Thank you for reporting us your feedback!

The internal ticket has been created: https://warthogs.atlassian.net/browse/KF-5349.

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[NohaIhab]

from the juju logs above, it is the same issue we've seen in kfp integration tests canonical/kfp-operators#377
even tho the final error message is different, but it is the same traceback. The message is only different because it was changed in the operator code, see canonical/operator#1049
The fix in mysql was published in 8.0/edge but it has not yet been promoted to 8.0/stable, see the issue in mysql canonical/mysql-k8s-operator#337
so to move on, we should use 8.0/edge in mlflow integration tests as well and change it back to stable once the fix is promoted