icinga2-checks/check_nginx.py

#!/usr/bin/env python

import argparse
import sys

import requests

from checker import nagios


def check_nginx_status(url):
    try:
        response = requests.get(url)
        response.raise_for_status()
        return response.text
    except requests.exceptions.RequestException as e:
        print("CRITICAL - Unable to connect to Nginx stub_status: {}".format(e))
        sys.exit(2)


def parse_nginx_status(status):
    try:
        lines = status.strip().split("\n")
        data = {}
        for line in lines:
            parts = line.split()
            if "Active" in line:
                data["active_connections"] = int(parts[2])
            elif "server accepts handled requests" in line:
                continue
            elif len(parts) == 3 and parts[1].isdigit():
                data["accepted"] = int(parts[0])
                data["handled"] = int(parts[1])
                data["requests"] = int(parts[2])
            elif "Reading" in line:
                data["reading"] = int(parts[1])
                data["writing"] = int(parts[3])
                data["waiting"] = int(parts[5])
        return data
    except Exception as e:
        print(f'UNKNOWN: failed to parse status page: {e}')
        sys.exit(nagios.UNKNOWN)


def main():
    parser = argparse.ArgumentParser(description="Check Nginx status using stub_status.")
    parser.add_argument("--url", required=True, help="URL to Nginx stub_status.")
    parser.add_argument("--critical-active", type=int, default=0, help="Critical threshold for active connections. Default: disabled")
    parser.add_argument("--warning-active", type=int, default=0, help="Warning threshold for active connections. Default: disabled")
    parser.add_argument("--critical-waiting", type=int, default=0, help="Critical threshold for waiting connections. Default: disabled")
    parser.add_argument("--warning-waiting", type=int, default=0, help="Warning threshold for waiting connections. Default: disabled")
    args = parser.parse_args()

    status = check_nginx_status(args.url)
    data = parse_nginx_status(status)

    status_str = "Active connections: {active_connections}, Waiting: {waiting}, Accepted: {accepted}, Handled: {handled}, Requests: {requests}, Reading: {reading}, Writing: {writing}".format(**data)

    if args.warning_active > 0 and args.critical_active > 0 and args.warning_waiting > 0 and args.critical_waiting > 0:
        perfdata = "| active_connections={active_connections};{warning};{critical} waiting={waiting};{warning_waiting};{critical_waiting} accepted={accepted} handled={handled} requests={requests} reading={reading} writing={writing}".format(
            warning=args.warning_active,
            critical=args.critical_active,
            warning_waiting=args.warning_waiting,
            critical_waiting=args.critical_waiting,
            **data
        )
        if data["active_connections"] >= args.critical_active or data["waiting"] >= args.critical_waiting:
            print("CRITICAL:", status_str, perfdata)
            sys.exit(nagios.CRITICAL)
        elif data["active_connections"] >= args.warning_active or data["waiting"] >= args.warning_waiting:
            print("WARNING:", status_str, perfdata)
            sys.exit(nagios.WARNING)
        else:
            print("OK:", status_str)
            sys.exit(nagios.OK)
    else:
        perfdata = "| active_connections={active_connections} waiting={waiting} accepted={accepted} handled={handled} requests={requests} reading={reading} writing={writing}".format(
            **data
        )
        print("OK:", status_str)
        print('Critical and warning levels disabled.', perfdata)
        sys.exit(nagios.OK)


if __name__ == "__main__":
    main()