prometheus-pve-sd/prometheuspvesd/cli.py
2021-06-09 20:44:10 +02:00

112 lines
3.6 KiB
Python

#!/usr/bin/env python3
"""Entrypoint and CLI handler."""
import argparse
import json
import shutil
import signal
import tempfile
from time import sleep
import prometheuspvesd.exception
from prometheuspvesd import __version__
from prometheuspvesd.config import SingleConfig
from prometheuspvesd.discovery import Discovery
from prometheuspvesd.model import HostList
from prometheuspvesd.utils import SingleLog
class PrometheusSD:
"""Main Prometheus SD object."""
def __init__(self):
self.log = SingleLog()
self.logger = self.log.logger
self.args = self._cli_args()
self.config = self._get_config()
self.discovery = Discovery()
self._fetch()
def _cli_args(self):
"""
Use argparse for parsing CLI arguments.
:return: args objec
"""
parser = argparse.ArgumentParser(description="Prometheus Service Discovery for Proxmox VE")
parser.add_argument(
"-c", "--config", dest="config_file", help="location of configuration file"
)
parser.add_argument(
"-o", "--output", dest="output_file", action="store", help="output file"
)
parser.add_argument(
"-v", dest="logging.level", action="append_const", const=-1, help="increase log level"
)
parser.add_argument(
"-q", dest="logging.level", action="append_const", const=1, help="decrease log level"
)
parser.add_argument(
"--version", action="version", version="%(prog)s {}".format(__version__)
)
return parser.parse_args().__dict__
def _get_config(self):
try:
config = SingleConfig(args=self.args)
except prometheuspvesd.exception.ConfigError as e:
self.log.sysexit_with_message(e)
try:
self.log.set_level(config.config["logging"]["level"])
except ValueError as e:
self.log.sysexit_with_message("Can not set log level.\n{}".format(str(e)))
required = [("pve.server", config.config["pve"]["server"]),
("pve.user", config.config["pve"]["user"]),
("pve.password", config.config["pve"]["password"])]
for name, value in required:
if not value:
self.log.sysexit_with_message("Option '{}' is required but not set".format(name))
self.logger.info("Using config file {}".format(config.config_file))
return config
def _fetch(self):
signal.signal(signal.SIGINT, self._terminate)
signal.signal(signal.SIGTERM, self._terminate)
loop_delay = self.config.config["loop_delay"]
output_file = self.config.config["output_file"]
self.logger.info("Writes targets to {}".format(output_file))
while True:
self.logger.debug("Propagate from PVE")
self._write(self.discovery.propagate())
self.logger.info("Waiting {} seconds for next loop".format(loop_delay))
sleep(self.config.config["loop_delay"])
def _write(self, host_list: HostList):
output = []
for host in host_list.hosts:
output.append(host.to_sd_json())
# Write to tmp file and move after write
temp_file = tempfile.NamedTemporaryFile(mode="w", prefix="prometheus-pve-sd", delete=False)
with temp_file as tf:
json.dump(output, tf, indent=4)
shutil.move(temp_file.name, self.config.config["output_file"])
def _terminate(self, signal, frame):
self.log.sysexit_with_message("Terminating", code=0)
def main():
PrometheusSD()