PG 9.6 and lower does not have function called 'pg_current_wal_lsn()':
Bootstrap execution have exited with an error: {'S': 'ERROR', 'V': 'ERROR', 'C': '42883', 'M': 'function pg_current_wal_lsn() does not exist', 'H': 'No function matches the given name and argument types. You might need to add explicit type casts.', 'P': '3182', 'F': 'parse_func.c', 'L': '523', 'R': 'ParseFuncOrColumn'}
PG 9.6 and lower does not have function called 'pg_current_wal_lsn()':
Use instead pg_current_xlog_location().