DPE-4699 backup logging and other fixes (#471)

* port refactoring from k8s

* port backup refactor from k8s

* tests refactoring after changes

* bump libs

* remove duplicate call and missing mock

* split backup in three (aws, ceph, gcp)

Author: paulomach

lib/charms/mysql/v0/backups.py

@@ -55,12 +55,14 @@ def is_unit_blocked(self) -> bool:
 from charms.mysql.v0.mysql import (
     MySQLConfigureInstanceError,
     MySQLCreateClusterError,
+    MySQLCreateClusterSetError,
     MySQLDeleteTempBackupDirectoryError,
     MySQLDeleteTempRestoreDirectoryError,
     MySQLEmptyDataDirectoryError,
     MySQLExecuteBackupCommandsError,
     MySQLGetMemberStateError,
     MySQLInitializeJujuOperationsTableError,
+    MySQLKillSessionError,
     MySQLOfflineModeAndHiddenInstanceExistsError,
     MySQLPrepareBackupForRestoreError,
     MySQLRescanClusterError,
@@ -80,13 +82,14 @@ def is_unit_blocked(self) -> bool:
 from ops.charm import ActionEvent
 from ops.framework import Object
 from ops.jujuversion import JujuVersion
-from ops.model import ActiveStatus, BlockedStatus
+from ops.model import BlockedStatus, MaintenanceStatus
 
 from constants import MYSQL_DATA_DIR
 
 logger = logging.getLogger(__name__)
 
 MYSQL_BACKUPS = "mysql-backups"
+S3_INTEGRATOR_RELATION_NAME = "s3-parameters"
 
 # The unique Charmhub library identifier, never change it
 LIBID = "183844304be247129572309a5fb1e47c"
@@ -96,7 +99,7 @@ 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 = 8
+LIBPATCH = 9
 
 
 if typing.TYPE_CHECKING:
@@ -117,6 +120,10 @@ def __init__(self, charm: "MySQLOperatorCharm", s3_integrator: S3Requirer) -> No
         self.framework.observe(self.charm.on.restore_action, self._on_restore)
 
     # ------------------ Helpers ------------------
+    @property
+    def _s3_integrator_relation_exists(self) -> bool:
+        """Returns whether a relation with the s3-integrator exists."""
+        return bool(self.model.get_relation(S3_INTEGRATOR_RELATION_NAME))
 
     def _retrieve_s3_parameters(self) -> Tuple[Dict[str, str], List[str]]:
         """Retrieve S3 parameters from the S3 integrator relation.
@@ -176,11 +183,7 @@ def _upload_logs_to_s3(
 
         Returns: bool indicating success
         """
-        logs = f"""Stdout:
-{stdout}
-
-Stderr:
-{stderr}"""
+        logs = f"Stdout:\n{stdout}\n\nStderr:\n{stderr}"
         logger.debug(f"Logs to upload to S3 at location {log_filename}:\n{logs}")
 
         logger.info(
@@ -206,7 +209,7 @@ def _on_list_backups(self, event: ActionEvent) -> None:
 
         List backups available to restore by this application.
         """
-        if not self.charm.s3_integrator_relation_exists:
+        if not self._s3_integrator_relation_exists:
             event.fail("Missing relation with S3 integrator charm")
             return
 
@@ -222,7 +225,9 @@ def _on_list_backups(self, event: ActionEvent) -> None:
             event.set_results({"backups": self._format_backups_list(backups)})
         except Exception as e:
             error_message = (
-                e.message if hasattr(e, "message") else "Failed to retrieve backup ids from S3"
+                getattr(e, "message")
+                if hasattr(e, "message")
+                else "Failed to retrieve backup ids from S3"
             )
             logger.error(error_message)
             event.fail(error_message)
@@ -233,7 +238,7 @@ def _on_create_backup(self, event: ActionEvent) -> None:
         """Handle the create backup action."""
         logger.info("A backup has been requested on unit")
 
-        if not self.charm.s3_integrator_relation_exists:
+        if not self._s3_integrator_relation_exists:
             logger.error("Backup failed: missing relation with S3 integrator charm")
             event.fail("Missing relation with S3 integrator charm")
             return
@@ -263,12 +268,13 @@ def _on_create_backup(self, event: ActionEvent) -> None:
 
         # Test uploading metadata to S3 to test credentials before backup
         juju_version = JujuVersion.from_environ()
-        metadata = f"""Date Backup Requested: {datetime_backup_requested}
-Model Name: {self.model.name}
-Application Name: {self.model.app.name}
-Unit Name: {self.charm.unit.name}
-Juju Version: {str(juju_version)}
-"""
+        metadata = (
+            f"Date Backup Requested: {datetime_backup_requested}\n"
+            f"Model Name: {self.model.name}\n"
+            f"Application Name: {self.model.app.name}\n"
+            f"Unit Name: {self.charm.unit.name}\n"
+            f"Juju Version: {str(juju_version)}\n"
+        )
 
         if not upload_content_to_s3(metadata, f"{backup_path}.metadata", s3_parameters):
             logger.error("Backup failed: Failed to upload metadata to provided S3")
@@ -313,6 +319,7 @@ def _on_create_backup(self, event: ActionEvent) -> None:
                 "backup-id": datetime_backup_requested,
             }
         )
+        self.charm._on_update_status(None)
 
     def _can_unit_perform_backup(self) -> Tuple[bool, Optional[str]]:
         """Validates whether this unit can perform a backup.
@@ -380,8 +387,9 @@ def _backup(self, backup_path: str, s3_parameters: Dict) -> Tuple[bool, Optional
         Returns: tuple of (success, error_message)
         """
         try:
+            self.charm.unit.status = MaintenanceStatus("Running backup...")
             logger.info("Running the xtrabackup commands")
-            stdout = self.charm._mysql.execute_backup_commands(
+            stdout, _ = self.charm._mysql.execute_backup_commands(
                 backup_path,
                 s3_parameters,
             )
@@ -436,7 +444,7 @@ def _pre_restore_checks(self, event: ActionEvent) -> bool:
 
         Returns: a boolean indicating whether restore should be run
         """
-        if not self.charm.s3_integrator_relation_exists:
+        if not self._s3_integrator_relation_exists:
             error_message = "Missing relation with S3 integrator charm"
             logger.error(f"Restore failed: {error_message}")
             event.fail(error_message)
@@ -481,7 +489,7 @@ def _on_restore(self, event: ActionEvent) -> None:
         if not self._pre_restore_checks(event):
             return
 
-        backup_id = event.params.get("backup-id").strip().strip("/")
+        backup_id = event.params["backup-id"].strip().strip("/")
         logger.info(f"A restore with backup-id {backup_id} has been requested on unit")
 
         # Retrieve and validate missing S3 parameters
@@ -500,6 +508,7 @@ def _on_restore(self, event: ActionEvent) -> None:
             return
 
         # Run operations to prepare for the restore
+        self.charm.unit.status = MaintenanceStatus("Running pre-restore operations")
         success, error_message = self._pre_restore()
         if not success:
             logger.error(f"Restore failed: {error_message}")
@@ -520,6 +529,7 @@ def _on_restore(self, event: ActionEvent) -> None:
             return
 
         # Run post-restore operations
+        self.charm.unit.status = MaintenanceStatus("Running post-restore operations")
         success, error_message = self._post_restore()
         if not success:
             logger.error(f"Restore failed: {error_message}")
@@ -533,22 +543,29 @@ def _on_restore(self, event: ActionEvent) -> None:
                 "completed": "ok",
             }
         )
+        # update status as soon as possible
+        self.charm._on_update_status(None)
 
-    def _pre_restore(self) -> Tuple[bool, Optional[str]]:
+    def _pre_restore(self) -> Tuple[bool, str]:
         """Perform operations that need to be done before performing a restore.
 
         Returns: tuple of (success, error_message)
         """
+        if not self.charm._mysql.is_mysqld_running():
+            return True, ""
+
         try:
+            logger.info("Stopping mysqld before restoring the backup")
+            self.charm._mysql.kill_client_sessions()
             self.charm._mysql.stop_mysqld()
+        except MySQLKillSessionError:
+            return False, "Failed to kill client sessions"
         except MySQLStopMySQLDError:
             return False, "Failed to stop mysqld"
 
-        return True, None
+        return True, ""
 
-    def _restore(
-        self, backup_id: str, s3_parameters: Dict[str, str]
-    ) -> Tuple[bool, bool, Optional[str]]:
+    def _restore(self, backup_id: str, s3_parameters: Dict[str, str]) -> Tuple[bool, bool, str]:
         """Run the restore operations.
 
         Args:
@@ -558,18 +575,21 @@ def _restore(
         Returns: tuple of (success, recoverable_error, error_message)
         """
         try:
-            logger.info("Running xbcloud get commands to retrieve the backup")
+            logger.info(
+                "Running xbcloud get commands to retrieve the backup\n"
+                "This operation can take long time depending on backup size and network speed"
+            )
+            self.charm.unit.status = MaintenanceStatus("Downloading backup...")
             stdout, stderr, backup_location = self.charm._mysql.retrieve_backup_with_xbcloud(
                 backup_id,
                 s3_parameters,
             )
-            logger.debug(f"Stdout of xbcloud get commands: {stdout}")
-            logger.debug(f"Stderr of xbcloud get commands: {stderr}")
         except MySQLRetrieveBackupWithXBCloudError:
             return False, True, f"Failed to retrieve backup {backup_id}"
 
         try:
             logger.info("Preparing retrieved backup using xtrabackup prepare")
+            self.charm.unit.status = MaintenanceStatus("Preparing for restore backup...")
             stdout, stderr = self.charm._mysql.prepare_backup_for_restore(backup_location)
             logger.debug(f"Stdout of xtrabackup prepare command: {stdout}")
             logger.debug(f"Stderr of xtrabackup prepare command: {stderr}")
@@ -583,16 +603,17 @@ def _restore(
             return False, False, "Failed to empty the data directory"
 
         try:
+            self.charm.unit.status = MaintenanceStatus("Restoring backup...")
             logger.info("Restoring the backup")
             stdout, stderr = self.charm._mysql.restore_backup(backup_location)
             logger.debug(f"Stdout of xtrabackup move-back command: {stdout}")
             logger.debug(f"Stderr of xtrabackup move-back command: {stderr}")
         except MySQLRestoreBackupError:
             return False, False, f"Failed to restore backup {backup_id}"
 
-        return True, True, None
+        return True, True, ""
 
-    def _clean_data_dir_and_start_mysqld(self) -> Tuple[bool, Optional[str]]:
+    def _clean_data_dir_and_start_mysqld(self) -> Tuple[bool, str]:
         """Run idempotent operations run after restoring a backup.
 
         Returns tuple of (success, error_message)
@@ -613,9 +634,9 @@ def _clean_data_dir_and_start_mysqld(self) -> Tuple[bool, Optional[str]]:
         except MySQLStartMySQLDError:
             return False, "Failed to start mysqld"
 
-        return True, None
+        return True, ""
 
-    def _post_restore(self) -> Tuple[bool, Optional[str]]:
+    def _post_restore(self) -> Tuple[bool, str]:
         """Run operations required after restoring a backup.
 
         Returns: tuple of (success, error_message)
@@ -638,24 +659,18 @@ def _post_restore(self) -> Tuple[bool, Optional[str]]:
             logger.info("Creating cluster on restored node")
             unit_label = self.charm.unit.name.replace("/", "-")
             self.charm._mysql.create_cluster(unit_label)
+            self.charm._mysql.create_cluster_set()
             self.charm._mysql.initialize_juju_units_operations_table()
 
             self.charm._mysql.rescan_cluster()
 
-            logger.info("Retrieving instance cluster state and role")
-            state, role = self.charm._mysql.get_member_state()
         except MySQLCreateClusterError:
             return False, "Failed to create InnoDB cluster on restored instance"
+        except MySQLCreateClusterSetError:
+            return False, "Failed to create InnoDB cluster-set on restored instance"
         except MySQLInitializeJujuOperationsTableError:
             return False, "Failed to initialize the juju operations table"
         except MySQLRescanClusterError:
             return False, "Failed to rescan the cluster"
-        except MySQLGetMemberStateError:
-            return False, "Failed to retrieve member state in restored instance"
 
-        self.charm.unit_peer_data["member-role"] = role
-        self.charm.unit_peer_data["member-state"] = state
-
-        self.charm.unit.status = ActiveStatus()
-
-        return True, None
+        return True, ""