How to use the glances.logger.logger.critical function in Glances

# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program. If not, see .

import sys

from glances.logger import logger

# Import mandatory PySNMP lib
try:
    from pysnmp.entity.rfc3413.oneliner import cmdgen
except ImportError:
    logger.critical("PySNMP library not found. To install it: pip install pysnmp")
    sys.exit(2)


class GlancesSNMPClient(object):

    """SNMP client class (based on pysnmp library)."""

    def __init__(self, host='localhost', port=161, version='2c',
                 community='public', user='private', auth=''):

        super(GlancesSNMPClient, self).__init__()
        self.cmdGen = cmdgen.CommandGenerator()

        self.version = version

        self.host = host

def init(self):
        """Init the connection to the Kafka server."""
        if not self.export_enable:
            return None

        # Build the server URI with host and port
        server_uri = '{}:{}'.format(self.host, self.port)

        try:
            s = KafkaProducer(bootstrap_servers=server_uri,
                              value_serializer=lambda v: json.dumps(v).encode('utf-8'),
                              compression_type=self.compression)
        except Exception as e:
            logger.critical("Cannot connect to Kafka server %s (%s)" % (server_uri, e))
            sys.exit(2)
        else:
            logger.info("Connected to the Kafka server %s" % server_uri)

        return s

def init(self):
        """Init the connection to the ES server."""
        if not self.export_enable:
            return None

        try:
            es = Elasticsearch(hosts=['{}:{}'.format(self.host, self.port)])
        except Exception as e:
            logger.critical("Cannot connect to ElasticSearch server %s:%s (%s)" % (self.host, self.port, e))
            sys.exit(2)
        else:
            logger.info("Connected to the ElasticSearch server %s:%s" % (self.host, self.port))

        try:
            index_count = es.count(index=self.index)['count']
        except Exception as e:
            # Index did not exist, it will be created at the first write
            # Create it...
            es.indices.create(self.index)
        else:
            logger.info("There is already %s entries in the ElasticSearch %s index" % (index_count, self.index))

        return es

from glances.compat import to_ascii, nativestr, b, u, itervalues
from glances.globals import MACOS, WINDOWS
from glances.logger import logger
from glances.events import glances_events
from glances.processes import glances_processes
from glances.timer import Timer

# Import curses library for "normal" operating system
if not WINDOWS:
    try:
        import curses
        import curses.panel
        from curses.textpad import Textbox
    except ImportError:
        logger.critical("Curses module not found. Glances cannot start in standalone mode.")
        sys.exit(1)


class _GlancesCurses(object):

    """This class manages the curses display (and key pressed).

    Note: It is a private class, use GlancesCursesClient or GlancesCursesBrowser.
    """

    _hotkeys = {
        '0': {'switch': 'disable_irix'},
        '1': {'switch': 'percpu'},
        '2': {'switch': 'disable_left_sidebar'},
        '3': {'switch': 'disable_quicklook'},
        '6': {'switch': 'meangpu'},

# Init
        self.config = config
        self.args = args

        # Init windows positions
        self.term_w = 80
        self.term_h = 24

        # Space between stats
        self.space_between_column = 3
        self.space_between_line = 2

        # Init the curses screen
        self.screen = curses.initscr()
        if not self.screen:
            logger.critical("Cannot init the curses library.\n")
            sys.exit(1)

        # Load the 'outputs' section of the configuration file
        # - Init the theme (default is black)
        self.theme = {'name': 'black'}

        # Load configuration file
        self.load_config(config)

        # Init cursor
        self._init_cursor()

        # Init the colors
        self._init_colors()

        # Init main window

def init(self):
        """Init the connection to the InfluxDB server."""
        if not self.export_enable:
            return None

        # Cluster
        try:
            cluster = Cluster([self.host],
                              port=int(self.port),
                              protocol_version=int(self.protocol_version))
            session = cluster.connect()
        except Exception as e:
            logger.critical("Cannot connect to Cassandra cluster '%s:%s' (%s)" % (self.host, self.port, e))
            sys.exit(2)

        # Keyspace
        try:
            session.set_keyspace(self.keyspace)
        except InvalidRequest as e:
            logger.info("Create keyspace {} on the Cassandra cluster".format(self.keyspace))
            c = "CREATE KEYSPACE %s WITH replication = { 'class': 'SimpleStrategy', 'replication_factor': '%s' }" % (self.keyspace, self.replication_factor)
            session.execute(c)
            session.set_keyspace(self.keyspace)

        logger.info(
            "Stats will be exported to Cassandra cluster {} ({}) in keyspace {}".format(
                cluster.metadata.cluster_name, cluster.metadata.all_hosts(), self.keyspace))

        # Table

def update(self):
        """Update stats from Glances/SNMP server."""
        if self.client_mode == 'glances':
            return self.update_glances()
        elif self.client_mode == 'snmp':
            return self.update_snmp()
        else:
            self.end()
            logger.critical("Unknown server mode: {}".format(self.client_mode))
            sys.exit(2)

# Should be set to True to generate graphs
        args.generate_graph = False

        # Control parameter and exit if it is not OK
        self.args = args

        # Export is only available in standalone or client mode (issue #614)
        export_tag = self.args.export is not None and any(self.args.export)
        if WINDOWS and export_tag:
            # On Windows, export is possible but only in quiet mode
            # See issue #1038
            logger.info("On Windows OS, export disable the Web interface")
            self.args.quiet = True
            self.args.webserver = False
        elif not (self.is_standalone() or self.is_client()) and export_tag:
            logger.critical("Export is only available in standalone or client mode")
            sys.exit(2)

        # Filter is only available in standalone mode
        if args.process_filter is not None and not self.is_standalone():
            logger.critical(
                "Process filter is only available in standalone mode")
            sys.exit(2)

        # Disable HDDTemp if sensors are disabled
        if getattr(args, 'disable_sensors', False):
            disable(args, 'hddtemp')
            logger.debug("Sensors and HDDTemp are disabled")

        return args

# The key is the plugin name
        # for example, the file glances_xxx.py
        # generate self._plugins_list["xxx"] = ...
        name = plugin_script[len(self.header):-3].lower()
        try:
            # Import the plugin
            plugin = __import__(plugin_script[:-3])
            # Init and add the plugin to the dictionary
            if name in ('help', 'amps', 'ports'):
                self._plugins[name] = plugin.Plugin(args=args, config=config)
            else:
                self._plugins[name] = plugin.Plugin(args=args)
        except Exception as e:
            # If a plugin can not be log, display a critical message
            # on the console but do not crash
            logger.critical("Error while initializing the {} plugin ({})".format(name, e))
            logger.error(traceback.format_exc())

"""Load the plugin (script), init it and add to the _plugin dict."""
        # The key is the plugin name
        # for example, the file glances_xxx.py
        # generate self._plugins_list["xxx"] = ...
        name = plugin_script[len(self.header):-3].lower()

        # Loaf the plugin class
        try:
            # Import the plugin
            plugin = __import__(plugin_script[:-3])
            # Init and add the plugin to the dictionary
            self._plugins[name] = plugin.Plugin(args=args, config=config)
        except Exception as e:
            # If a plugin can not be loaded, display a critical message
            # on the console but do not crash
            logger.critical("Error while initializing the {} plugin ({})".format(name, e))
            logger.error(traceback.format_exc())
            # Disable the plugin
            if args is not None:
                setattr(args,
                        'disable_' + name,
                        False)
        else:
            # Set the disable_ to False by default
            if args is not None:
                setattr(args,
                        'disable_' + name,
                        getattr(args, 'disable_' + name, False))