fix(longevity): get table for 'add_drop_column'

If run disrupt_add_remove_dc nemesis in parallel to the disrupt_add_drop_column one then we can
get following error:

  KeyError: 'keyspace_new_dc'

It is caused by the concurrency of a new keyspace addition (disrupt_add_remove_dc nemesis)
and driver session update in addition to the unsafe coding assuming driver's session
(disrupt_add_drop_column nemesis) knows about that newly added keyspace.
Another possible problem: new added keyspace was dropped in exacly time when we run
describe of the table.

Fixes: #7240

sdcm/nemesis.py

@@ -2040,7 +2040,7 @@ def _get_all_tables_with_no_compact_storage(self, tables_to_skip=None):
         if tables_to_skip is None:
             tables_to_skip = {}
         to_be_skipped_default = tables_to_skip.get('*', '').split(',')
-        with self.cluster.cql_connection_patient(self.tester.db_cluster.nodes[0]) as session:
+        with self.cluster.cql_connection_patient(self.target_node) as session:
             query_result = session.execute('SELECT keyspace_name FROM system_schema.keyspaces;')
             for result_rows in query_result:
                 keyspaces.extend([row.lower()
@@ -2055,7 +2055,10 @@ def _get_all_tables_with_no_compact_storage(self, tables_to_skip=None):
                     to_be_skipped = []
                 else:
                     to_be_skipped = to_be_skipped.split(',') + to_be_skipped_default
-                tables = get_db_tables(session, ks, with_compact_storage=False)
+                tables = get_db_tables(session=session,
+                                       keyspace_name=ks,
+                                       node=self.target_node,
+                                       with_compact_storage=False)
                 if to_be_skipped:
                     tables = [table for table in tables if table not in to_be_skipped]
                 if not tables:

sdcm/utils/common.py

@@ -54,6 +54,7 @@
 
 import requests
 import boto3
+from invoke import UnexpectedExit
 from mypy_boto3_s3 import S3Client, S3ServiceResource
 from mypy_boto3_ec2 import EC2Client, EC2ServiceResource
 from mypy_boto3_ec2.service_resource import Image as EC2Image
@@ -67,6 +68,7 @@
 
 from sdcm.provision.aws.capacity_reservation import SCTCapacityReservation
 from sdcm.provision.azure.provisioner import AzureProvisioner
+from sdcm.remote.libssh2_client import UnexpectedExit as Libssh2_UnexpectedExit
 from sdcm.sct_events import Severity
 from sdcm.sct_events.system import CpuNotHighEnoughEvent, SoftTimeoutEvent
 from sdcm.utils.argus import ArgusError, get_argus_client, terminate_resource_in_argus
@@ -2106,7 +2108,7 @@ def get_ami_tags(ami_id, region_name):
             return {}
 
 
-def get_db_tables(session, ks, with_compact_storage=True):
+def get_db_tables(session, keyspace_name, node, with_compact_storage=True):
     """
     Return tables from keystore based on their compact storage feature
     Arguments:
@@ -2116,12 +2118,19 @@ def get_db_tables(session, ks, with_compact_storage=True):
 
     """
     output = []
-    for table in list(session.cluster.metadata.keyspaces[ks].tables.keys()):
-        table_code = session.cluster.metadata.keyspaces[ks].tables[table].as_cql_query()
-        if with_compact_storage is None:
-            output.append(table)
-        elif ("with compact storage" in table_code.lower()) == with_compact_storage:
-            output.append(table)
+    for row in list(session.execute(f"select table_name from system_schema.tables where keyspace_name='{keyspace_name}'")):
+        try:
+            create_table_statement = node.run_cqlsh(f"describe {keyspace_name}.{row.table_name}").stdout.upper()
+        except (UnexpectedExit, Libssh2_UnexpectedExit) as err:
+            # SCT issue https://github.com/scylladb/scylla-cluster-tests/issues/7240
+            # May happen when disrupt_add_remove_dc nemesis run in parallel to the disrupt_add_drop_column
+            LOGGER.error("Failed to describe '%s.%s' table. Maybe the table has been deleted. Error: %s",
+                         keyspace_name, row.table_name, err.result.stderr)
+            continue
+
+        if with_compact_storage is None or (("WITH COMPACT STORAGE" in create_table_statement) == with_compact_storage):
+            output.append(row.table_name)
+
     return output