Port over charm lib changes from k8s charm relating to pod reschdule …

…during cluster setup (#518)

* Port over charm lib changes from k8s charm relating to pod reschdule during cluster setup

* Update outdated cos_agent charmlib

* Add unit test

* Update outdated tracing charm lib

* Fix typo

lib/charms/mysql/v0/backups.py

@@ -60,9 +60,9 @@ def is_unit_blocked(self) -> bool:
     MySQLDeleteTempRestoreDirectoryError,
     MySQLEmptyDataDirectoryError,
     MySQLExecuteBackupCommandsError,
-    MySQLGetMemberStateError,
     MySQLInitializeJujuOperationsTableError,
     MySQLKillSessionError,
+    MySQLNoMemberStateError,
     MySQLOfflineModeAndHiddenInstanceExistsError,
     MySQLPrepareBackupForRestoreError,
     MySQLRescanClusterError,
@@ -73,6 +73,7 @@ def is_unit_blocked(self) -> bool:
     MySQLSetInstanceOptionError,
     MySQLStartMySQLDError,
     MySQLStopMySQLDError,
+    MySQLUnableToGetMemberStateError,
 )
 from charms.mysql.v0.s3_helpers import (
     fetch_and_check_existence_of_s3_path,
@@ -99,7 +100,7 @@ def is_unit_blocked(self) -> bool:
 
 # Increment this PATCH version before using `charmcraft publish-lib` or reset
 # to 0 if you are raising the major API version
-LIBPATCH = 11
+LIBPATCH = 12
 
 
 if typing.TYPE_CHECKING:
@@ -339,7 +340,7 @@ def _can_unit_perform_backup(self) -> Tuple[bool, Optional[str]]:
 
         try:
             state, role = self.charm._mysql.get_member_state()
-        except MySQLGetMemberStateError:
+        except (MySQLNoMemberStateError, MySQLUnableToGetMemberStateError):
             return False, "Error obtaining member state"
 
         if role == "primary" and self.charm.app.planned_units() > 1:

lib/charms/mysql/v0/mysql.py

@@ -134,7 +134,7 @@ def wait_until_mysql_connection(self) -> None:
 # Increment this major API version when introducing breaking changes
 LIBAPI = 0
 
-LIBPATCH = 72
+LIBPATCH = 73
 
 UNIT_TEARDOWN_LOCKNAME = "unit-teardown"
 UNIT_ADD_LOCKNAME = "unit-add"
@@ -276,8 +276,12 @@ class MySQLGrantPrivilegesToUserError(Error):
     """Exception raised when there is an issue granting privileges to user."""
 
 
-class MySQLGetMemberStateError(Error):
-    """Exception raised when there is an issue getting member state."""
+class MySQLNoMemberStateError(Error):
+    """Exception raised when there is no member state."""
+
+
+class MySQLUnableToGetMemberStateError(Error):
+    """Exception raised when unable to get member state."""
 
 
 class MySQLGetClusterEndpointsError(Error):
@@ -620,6 +624,26 @@ def cluster_initialized(self) -> bool:
 
         return False
 
+    @property
+    def only_one_cluster_node_thats_uninitialized(self) -> Optional[bool]:
+        """Check if only a single cluster node exists across all units."""
+        if not self.app_peer_data.get("cluster-name"):
+            return None
+
+        total_cluster_nodes = 0
+        for unit in self.app_units:
+            total_cluster_nodes += self._mysql.get_cluster_node_count(
+                from_instance=self.get_unit_address(unit)
+            )
+
+        total_online_cluster_nodes = 0
+        for unit in self.app_units:
+            total_online_cluster_nodes += self._mysql.get_cluster_node_count(
+                from_instance=self.get_unit_address(unit), node_status=MySQLMemberState["ONLINE"]
+            )
+
+        return total_cluster_nodes == 1 and total_online_cluster_nodes == 0
+
     @property
     def cluster_fully_initialized(self) -> bool:
         """Returns True if the cluster is fully initialized.
@@ -1728,6 +1752,18 @@ def is_instance_configured_for_innodb(
             )
             return False
 
+    def drop_group_replication_metadata_schema(self) -> None:
+        """Drop the group replication metadata schema from current unit."""
+        commands = (
+            f"shell.connect('{self.instance_def(self.server_config_user)}')",
+            "dba.drop_metadata_schema()",
+        )
+
+        try:
+            self._run_mysqlsh_script("\n".join(commands))
+        except MySQLClientError:
+            logger.exception("Failed to drop group replication metadata schema")
+
     def are_locks_acquired(self, from_instance: Optional[str] = None) -> bool:
         """Report if any topology change is being executed."""
         commands = (
@@ -2356,13 +2392,13 @@ def get_member_state(self) -> Tuple[str, str]:
             logger.error(
                 "Failed to get member state: mysqld daemon is down",
             )
-            raise MySQLGetMemberStateError(e.message)
+            raise MySQLUnableToGetMemberStateError(e.message)
 
         # output is like:
         # 'MEMBER_STATE\tMEMBER_ROLE\tMEMBER_ID\t@@server_uuid\nONLINE\tPRIMARY\t<uuid>\t<uuid>\n'
         lines = output.strip().lower().split("\n")
         if len(lines) < 2:
-            raise MySQLGetMemberStateError("No member state retrieved")
+            raise MySQLNoMemberStateError("No member state retrieved")
 
         if len(lines) == 2:
             # Instance just know it own state
@@ -2378,7 +2414,7 @@ def get_member_state(self) -> Tuple[str, str]:
                 # filter server uuid
                 return results[0], results[1] or "unknown"
 
-        raise MySQLGetMemberStateError("No member state retrieved")
+        raise MySQLNoMemberStateError("No member state retrieved")
 
     def is_cluster_replica(self, from_instance: Optional[str] = None) -> Optional[bool]:
         """Check if this cluster is a replica in a cluster set."""
@@ -2435,7 +2471,7 @@ def hold_if_recovering(self) -> None:
         while True:
             try:
                 member_state, _ = self.get_member_state()
-            except MySQLGetMemberStateError:
+            except (MySQLNoMemberStateError, MySQLUnableToGetMemberStateError):
                 break
             if member_state == MySQLMemberState.RECOVERING:
                 logger.debug("Unit is recovering")

lib/charms/tempo_k8s/v2/tracing.py

@@ -97,7 +97,7 @@ def __init__(self, *args):
 )
 from ops.framework import EventSource, Object
 from ops.model import ModelError, Relation
-from pydantic import BaseModel, ConfigDict, Field
+from pydantic import BaseModel, Field
 
 # The unique Charmhub library identifier, never change it
 LIBID = "12977e9aa0b34367903d8afeb8c3d85d"
@@ -107,7 +107,7 @@ def __init__(self, *args):
 
 # Increment this PATCH version before using `charmcraft publish-lib` or reset
 # to 0 if you are raising the major API version
-LIBPATCH = 8
+LIBPATCH = 9
 
 PYDEPS = ["pydantic"]
 
@@ -338,7 +338,7 @@ class Config:
     class ProtocolType(BaseModel):
         """Protocol Type."""
 
-        model_config = ConfigDict(
+        model_config = ConfigDict(  # type: ignore
             # Allow serializing enum values.
             use_enum_values=True
         )
@@ -925,7 +925,7 @@ def get_endpoint(
 def charm_tracing_config(
     endpoint_requirer: TracingEndpointRequirer, cert_path: Optional[Union[Path, str]]
 ) -> Tuple[Optional[str], Optional[str]]:
-    """Utility function to determine the charm_tracing config you will likely want.
+    """Return the charm_tracing config you likely want.
 
     If no endpoint is provided:
      disable charm tracing.

src/charm.py

@@ -30,13 +30,14 @@
     MySQLCreateClusterError,
     MySQLCreateClusterSetError,
     MySQLGetClusterPrimaryAddressError,
-    MySQLGetMemberStateError,
     MySQLGetMySQLVersionError,
     MySQLInitializeJujuOperationsTableError,
     MySQLLockAcquisitionError,
+    MySQLNoMemberStateError,
     MySQLPluginInstallError,
     MySQLRebootFromCompleteOutageError,
     MySQLSetClusterPrimaryError,
+    MySQLUnableToGetMemberStateError,
 )
 from charms.mysql.v0.tls import MySQLTLS
 from charms.rolling_ops.v0.rollingops import RollingOpsManager
@@ -511,7 +512,7 @@ def _on_update_status(self, _) -> None:  # noqa: C901
             state, role = self._mysql.get_member_state()
             self.unit_peer_data["member-role"] = role
             self.unit_peer_data["member-state"] = state
-        except MySQLGetMemberStateError:
+        except (MySQLNoMemberStateError, MySQLUnableToGetMemberStateError):
             role = self.unit_peer_data["member-role"] = "unknown"
             state = self.unit_peer_data["member-state"] = "unreachable"
         logger.info(f"Unit workload member-state is {state} with member-role {role}")

tests/unit/test_backups.py

@@ -11,8 +11,8 @@
     MySQLDeleteTempRestoreDirectoryError,
     MySQLEmptyDataDirectoryError,
     MySQLExecuteBackupCommandsError,
-    MySQLGetMemberStateError,
     MySQLInitializeJujuOperationsTableError,
+    MySQLNoMemberStateError,
     MySQLOfflineModeAndHiddenInstanceExistsError,
     MySQLPrepareBackupForRestoreError,
     MySQLRescanClusterError,
@@ -356,7 +356,7 @@ def test_can_unit_perform_backup_failure(
         self.harness.remove_relation_unit(self.peer_relation_id, "mysql/1")
 
         # test error getting member state
-        _get_member_state.side_effect = MySQLGetMemberStateError
+        _get_member_state.side_effect = MySQLNoMemberStateError
 
         success, error_message = self.mysql_backups._can_unit_perform_backup()
         self.assertFalse(success)

tests/unit/test_mysql.py

@@ -29,12 +29,12 @@
     MySQLExecuteBackupCommandsError,
     MySQLGetAutoTuningParametersError,
     MySQLGetClusterPrimaryAddressError,
-    MySQLGetMemberStateError,
     MySQLGetMySQLVersionError,
     MySQLGetRouterUsersError,
     MySQLGetVariableError,
     MySQLInitializeJujuOperationsTableError,
     MySQLMemberState,
+    MySQLNoMemberStateError,
     MySQLOfflineModeAndHiddenInstanceExistsError,
     MySQLPluginInstallError,
     MySQLPrepareBackupForRestoreError,
@@ -463,6 +463,21 @@ def test_is_instance_configured_for_innodb(self, _run_mysqlsh_script):
         )
         self.assertFalse(is_instance_configured)
 
+    @patch("charms.mysql.v0.mysql.MySQLBase._run_mysqlsh_script")
+    def test_drop_group_replication_metadata_schema(self, _run_mysqlsh_script):
+        """Test with no exceptions while calling the drop_group_replication_metadata_schema method."""
+        # test successfully configured instance
+        drop_group_replication_metadata_schema_commands = (
+            "shell.connect('serverconfig:serverconfigpassword@127.0.0.1:33062')",
+            "dba.drop_metadata_schema()",
+        )
+
+        self.mysql.drop_group_replication_metadata_schema()
+
+        _run_mysqlsh_script.assert_called_once_with(
+            "\n".join(drop_group_replication_metadata_schema_commands)
+        )
+
     @patch("charms.mysql.v0.mysql.MySQLBase._run_mysqlsh_script")
     def test_is_instance_configured_for_innodb_exceptions(self, _run_mysqlsh_script):
         """Test an exception while calling the is_instance_configured_for_innodb method."""
@@ -835,7 +850,7 @@ def test_get_member_state(self, _run_mysqlcli_script):
 
         _run_mysqlcli_script.return_value = "MEMBER_STATE\tMEMBER_ROLE\tMEMBER_ID\t@@server_uuid\n"
 
-        with self.assertRaises(MySQLGetMemberStateError):
+        with self.assertRaises(MySQLNoMemberStateError):
             self.mysql.get_member_state()
 
     @patch("charms.mysql.v0.mysql.MySQLBase._run_mysqlsh_script")