dump_instance.sh and load_instance.sh scripts

Issue #65 - Prepare regression test covering database backup/restore

Issue #4 use database backup to restore HAF

The scripts save or load the haf database along with the hived state.

OPTIONS:
  --backup-dir=DIR                 Allows to specify where the dumps are located, required
  --hived-executable-path=PATH     Allows to specify where the main executable is located, required
  --hived-data-dir=DIR             Allows to specify where node data is located, required
  --haf-db-name=NAME               Allows to specify a name of database to store HAF data, required
  --haf-db-admin=NAME              Allows to specify a name of database admin role having permission to create the database
  --haf-db-host=VALUE              Allows to specify a PostgreSQL host location
  --haf-db-port=NUMBER             Allows to specify a PostgreSQL operating port
  --haf-db-jobs=NUMBER             Allows to specify how many processes are run during dump/restore
  --override-existing-backup-dir   Erases backup directory and its contents
  --help                           Display this help screen and exit

A note using Docker: hivemind SELECT * on hivemind_app view issues an error "could not resize shared memory segment" . Fixed by adding --shm-size=2gb to the docker run command.

tests/integration/system/haf/test_pg_dump.py

@@ -104,8 +104,8 @@ def pg_restore(target_db_name):
 
 def compare_databases(source_session, target_session):
     ask_for_tables_and_views_sql = f"select table_name from information_schema.tables where table_schema = 'hive'"
-    source_tables = execute_sql_one_column(source_session, ask_for_tables_and_views_sql)
-    target_tables = execute_sql_one_column(target_session, ask_for_tables_and_views_sql)
+    source_tables = execute_sql_col(source_session, ask_for_tables_and_views_sql)
+    target_tables = execute_sql_col(target_session, ask_for_tables_and_views_sql)
 
     source_tables.sort()
     target_tables.sort()
@@ -121,9 +121,9 @@ def compare_databases(source_session, target_session):
 
         
 def take_table_contents(session, table):
-    recordset = execute_sql(session, f"SELECT column_name FROM information_schema.columns  WHERE table_schema = 'hive' AND table_name   = '{table}';")
+    recordset = execute_sql_row(session, f"SELECT column_name FROM information_schema.columns  WHERE table_schema = 'hive' AND table_name   = '{table}';")
     columns = ', '.join([e[0] for e in (recordset)])
-    return execute_sql(session, f"SELECT * FROM hive.{table} ORDER BY {columns}")
+    return execute_sql_row(session, f"SELECT * FROM hive.{table} ORDER BY {columns}")
 
 
 def compare_psql_tool_dumped_schemas(source_session, target_session):
@@ -146,11 +146,11 @@ def shell(command):
     subprocess.call(command, shell=True)
 
 
-def execute_sql_one_column(session, s):
+def execute_sql_col(session, s):
     return [e[0] for e in session.execute(s)]
 
 
-def execute_sql(session, s):
+def execute_sql_row(session, s):
     return [e for e in session.execute(s)]