Uptime Healthcheck Monitor

I have designed a lightweight Python monitor for your HTTP endpoint and Docker container. The implementation uses a state-change logic to ensure you only receive Telegram notifications when a service goes down or recovers.

Uptime Monitor Implementation

1. Python Monitor Script (monitor.py)

import os
import json
import requests
import subprocess
from datetime import datetime

# Configuration from environment
TELEGRAM_TOKEN = os.getenv("TELEGRAM_TOKEN")
CHAT_ID = os.getenv("CHAT_ID")
STATE_FILE = "monitor_state.json"

TARGETS = [
    {"type": "http", "name": "example-site", "url": "https://example.com", "timeout": 10},
    {"type": "docker", "name": "db-worker", "container": "db-worker"}
]

def get_state():
    if os.path.exists(STATE_FILE):
        with open(STATE_FILE, 'r') as f:
            return json.load(f)
    return {}

def save_state(state):
    with open(STATE_FILE, 'w') as f:
        json.dump(state, f)

def notify(msg):
    url = f"https://api.telegram.org/bot{TELEGRAM_TOKEN}/sendMessage"
    payload = {"chat_id": CHAT_ID, "text": msg, "parse_mode": "Markdown"}
    try:
        requests.post(url, json=payload, timeout=10)
    except Exception as e:
        print(f"Failed to send alert: {e}")

def check_http(target):
    try:
        r = requests.get(target['url'], timeout=target['timeout'])
        return "UP" if r.status_code == 200 else "DOWN"
    except:
        return "DOWN"

def check_docker(target):
    try:
        res = subprocess.run(["docker", "inspect", "-f", "{{.State.Running}}", target['container']], 
                             capture_output=True, text=True)
        return "UP" if res.stdout.strip() == "true" else "DOWN"
    except:
        return "DOWN"

def main():
    current_state = get_state()
    for t in TARGETS:
        status = check_http(t) if t['type'] == 'http' else check_docker(t)
        last_status = current_state.get(t['name'])
        
        if last_status and status != last_status:
            emoji = "✅" if status == "UP" else "🚨"
            notify(f"{emoji} *{t['name']}* state changed to {status}")
        
        current_state[t['name']] = status
    save_state(current_state)

if __name__ == "__main__":
    main()

2. Systemd Configuration (uptime-monitor.timer)

[Unit]
Description=Run Uptime Monitor every 5 minutes

[Timer]
OnBootSec=2min
OnUnitActiveSec=5min
Unit=uptime-monitor.service

[Install]
WantedBy=timers.target

Next steps

• Create a .env file with your TELEGRAM_TOKEN and CHAT_ID.
• Ensure your user is in the docker group to allow the script to inspect containers.
• Copy the unit files to /etc/systemd/system/ and run systemctl enable --now uptime-monitor.timer.