# -*- coding: utf-8 -*-
#
# This file is part of Glances.
#
# SPDX-FileCopyrightText: 2022 Nicolas Hennion <nicolas@nicolargo.com>
#
# SPDX-License-Identifier: LGPL-3.0-only
#
"""ZeroMQ interface class."""
import sys
from glances.compat import b
from glances.logger import logger
from glances.exports.glances_export import GlancesExport
from glances.globals import json_dumps
import zmq
from zmq.utils.strtypes import asbytes
class Export(GlancesExport):
"""This class manages the ZeroMQ export module."""
def __init__(self, config=None, args=None):
"""Init the ZeroMQ export IF."""
super(Export, self).__init__(config=config, args=args)
# Mandatory configuration keys (additional to host and port)
self.prefix = None
# Optionals configuration keys
# N/A
# Load the ZeroMQ configuration file section ([export_zeromq])
self.export_enable = self.load_conf('zeromq', mandatories=['host', 'port', 'prefix'], options=[])
if not self.export_enable:
exit('Missing ZEROMQ config')
# Init the ZeroMQ context
self.context = None
self.client = self.init()
def init(self):
"""Init the connection to the CouchDB server."""
if not self.export_enable:
return None
server_uri = 'tcp://{}:{}'.format(self.host, self.port)
try:
self.context = zmq.Context()
publisher = self.context.socket(zmq.PUB)
publisher.bind(server_uri)
except Exception as e:
logger.critical("Cannot connect to ZeroMQ server %s (%s)" % (server_uri, e))
sys.exit(2)
else:
logger.info("Connected to the ZeroMQ server %s" % server_uri)
return publisher
def exit(self):
"""Close the socket and context"""
if self.client is not None:
self.client.close()
if self.context is not None:
self.context.destroy()
def export(self, name, columns, points):
"""Write the points to the ZeroMQ server."""
logger.debug("Export {} stats to ZeroMQ".format(name))
# Create DB input
data = dict(zip(columns, points))
# Do not publish empty stats
if data == {}:
return False
# Glances envelopes the stats in a publish message with two frames:
# - First frame containing the following prefix (STRING)
# - Second frame with the Glances plugin name (STRING)
# - Third frame with the Glances plugin stats (JSON)
message = [b(self.prefix), b(name), asbytes(json_dumps(data))]
# Write data to the ZeroMQ bus
# Result can be view: tcp://host:port
try:
self.client.send_multipart(message)
except Exception as e:
logger.error("Cannot export {} stats to ZeroMQ ({})".format(name, e))
return True
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