#!/usr/bin/env python3 import configparser import fcntl import json import logging import os import socket import ssl import struct import subprocess import sys import xml.etree.ElementTree as ET from urllib.request import Request, urlopen from urllib.error import HTTPError, URLError MCS_SYSCONF_DIR = '@ENGINE_SYSCONFDIR@' MCS_ETC_PATH = os.path.join(MCS_SYSCONF_DIR, 'columnstore') CMAPI_CONFIG_PATH = os.path.join(MCS_ETC_PATH, 'cmapi_server.conf') MCS_CONFIG_PATH = os.path.join(MCS_ETC_PATH, 'Columnstore.xml') SM_CONFIG_PATH = os.path.join(MCS_ETC_PATH, 'storagemanager.cnf') MCS_BIN_DIR = '@ENGINE_BINDIR@' SAVEBRM = os.path.join(MCS_BIN_DIR, 'save_brm') HALF_A_MINUTE = 30 LOCALHOST = '127.0.0.1' # according to https://www.ibm.com/docs/en/storage-sentinel/1.1.2?topic=installation-map-your-local-host-loopback-address LOCALHOSTS = ( '127.0.0.1', 'localhost', 'localhost.localdomain', 'localhost4', 'localhost4.localdomain4', '::1', 'localhost6', 'localhost6.localdomain6', ) API_VERSION = '0.4.0' API_PORT = '8640' def get_api_key(): """Get API key from cmapi config file. :return: return api key :rtype: str """ cmapi_config = configparser.ConfigParser() cmapi_config.read(CMAPI_CONFIG_PATH) # dequote? return cmapi_config.get('Authentication', 'x-api-key', fallback='') def get_unverified_context(): ctx = ssl.create_default_context() ctx.check_hostname = False ctx.verify_mode = ssl.CERT_NONE return ctx def cmapi_available(): """Check if CMAPI server is running. :return: is CMAPI running or not :rtype: bool """ logging.debug('Detecting CMAPI is up and running.') url = 'https://{}:{}/notfound'.format(LOCALHOST, API_PORT) request = Request(method='POST', url=url) ctx = get_unverified_context() try: with urlopen(request, context=ctx, timeout=HALF_A_MINUTE) as req: _ = req.read().decode('utf-8') except HTTPError as exc: if exc.code == 404: return True except URLError: logging.info('CMAPI seems to be unavailable.') except Exception: logging.error( 'Undefined error while trying to check CMAPI availabale.', exc_info=True ) return False def get_ip_address_by_nic(ifname): """Get ip address for nic. :param ifname: network intarface name :type ifname: str :return: ip address :rtype: str """ # doesn't work on windows, # OpenBSD and probably doesn't on FreeBSD/pfSense either ip_addr = '' try: s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) ip_addr = socket.inet_ntoa( fcntl.ioctl( s.fileno(), 0x8915, # SIOCGIFADDR "socket ioctl get interface address" struct.pack('256s', bytes(ifname[:15], 'utf-8')) )[20:24] ) except Exception as exc: logging.debug( 'Exception while getting IP address of an "{}" interface'.format( ifname ), exc_info=True ) finally: s.close() return ip_addr def is_primary_fallback(current_hostname): """Detect is node primary or not without cmapi. :param current_hostname: hostname or FQDN :type current_hostname: str :return: is node primary :rtype: bool """ logging.debug( 'Current DBRM_Controller/IPAddr is {}'.format(current_hostname) ) hostnames = set() for _, nic_name in socket.if_nameindex(): ip_addr = get_ip_address_by_nic(nic_name) try: hostnames_3tuple = socket.gethostbyaddr(ip_addr) hostnames.update([hostnames_3tuple[0], *hostnames_3tuple[1]]) except: pass logging.debug('Found hostnames {}.'.format(hostnames)) return current_hostname in LOCALHOSTS or current_hostname in hostnames def is_node_primary(conf_root): """Detect is current node primary or not. :param conf_root: xml config root element :type conf_root: xml.etree.ElementTree.ElementTree :return: primary or not :rtype: bool """ if cmapi_available(): url = 'https://{}:{}/cmapi/{}/node/primary'.format( LOCALHOST, API_PORT, API_VERSION ) ctx = get_unverified_context() # Actually for this endpoint no need to provide api key cause it's # not required request = Request( method='GET', url=url, headers={'x-api-key': get_api_key()} ) success = False try: with urlopen(request, context=ctx, timeout=HALF_A_MINUTE) as req: response = req.read() success = True except HTTPError as exc: logging.warning( 'Something goes wrong while requesting primary status ', 'through api.', 'Got response code "{}" with reason "{}".'.format( exc.code, exc.reason ) ) except URLError: logging.warning( 'CMAPI became unavailable while trying', 'to request primary status.' ) except Exception: logging.error( 'Undefined exception while trying to request primary status.', exc_info=True ) if success: dict_response = json.loads(response.decode('utf-8')) is_primary = dict_response.get('is_primary', False) if is_primary and is_primary in ('True', 'true'): is_primary = True else: is_primary = False return is_primary logging.info('Trying to detect primary without cmapi running.') # text in tag have to be hostname or FQDN return is_primary_fallback(conf_root.find('./DBRM_Controller/IPAddr').text) if __name__ == '__main__': master_addr = '' pm_count = 0 logging.basicConfig( format='%(levelname)s: %(message)s', level=logging.DEBUG ) logging.debug('Loading Columnstore.xml.') try: cs_config = ET.parse(MCS_CONFIG_PATH) config_root = cs_config.getroot() master_addr = config_root.find('./DBRM_Controller/IPAddr').text pm_count = int( config_root.find('./SystemModuleConfig/ModuleCount3').text ) logging.debug('Succesfully loaded Columnstore.xml.') except (FileNotFoundError, AttributeError, ValueError) as e: # is it correct case? logging.error( 'Exception while loading Columnstore.xml. Continue anyway.', exc_info=True ) logging.debug('Reading SM config.') sm_config = configparser.ConfigParser() files_read = len(sm_config.read(SM_CONFIG_PATH)) storage = sm_config.get( 'ObjectStorage', 'service', fallback='LocalStorage' ) if is_node_primary(config_root): try: retcode = subprocess.check_call(SAVEBRM, shell=True) except subprocess.CalledProcessError as exc: logging.error('{} exits with {}.'.format(exc.cmd, exc.returncode)) sys.exit(1) except OSError: logging.error('Os error while calling savebrm', exc_info=True) sys.exit(0) sys.exit(0)