health-checks

A Simple Health Check Tool

Background

CloudFlare provides Health Checks but you have to be on a paid plan. Vultr provides Free-Tier VPS (512 MB, 1 Core, 10 GB SSD, 2 TB Bandwidth).

This lightweight VPS does not have much RAM - so it cannot run heavy applications, but this (health check) tool should be a good use case for it.

Acknowledgement

Most code at the "init commit" is done by ChatGPT. Thank you!

How to Run?

No docker - as you probably can't run docker on it. You can either run it in screen or pm2 (install via npm install pm2 -g) so that it will stay in background.

Config.json

Change config.json.sample to config.json and modify the content necessary - which should be pretty straightforward. If expectedContent is empty, this check will be ignored.

Run npm install to install the missing dependencies.

Here is a sample JSON config:

{
  "urls": [
    {
      "name": "Example Website",
      "url": "https://example.com",
      "interval": 60,
      "expectedStatusCode": 200,
      "expectedContent": "Example Domain",
      "ignore_period": 1800
    },
    {
      "name": "Google",
      "url": "https://www.google.com",
      "interval": 30,
      "expectedStatusCode": 200,
      "expectedContent": "Google",
      "ignore_period": 1800
    }
  ],
  "email": {
    "service": "Gmail",
    "auth": {
        "user": "your gmail account",
        "pass": "your gmail temp app password"
    },
    "destination": "email address that you wish to receive the notification",
    "interval": 3,
    "enabled": true
  }
}

The ignore_period for each url specifies the period that no two notifications will be handled. The email.enabled when set to false, will print to console instead of sending emails. The emails will be sent one per interval seconds.

Run Health-Checks

Simply Run node health-checks.js,

Example:

In case of failures:

You should get an email, if configured correctedly.

TODO:

Configure a max email per period (PR welcome)

Support

If you find this useful, why not buy me a coffee? Thanks!