HTTP Health Check Script

The health_check.py script performs a HTTP health check on given URLs and outputs the health status in JSON format. It checks the URLs using a multi-threaded approach and supports both full and simple reporting.

Requirements

This script was tested with the following software and system

Python 3
Ubuntu 22.04

Software Packages to be Installed

nginx
uwsgi-plugin-python3
uwsgi
uwsgi-emperor

Usage

The script accepts the following arguments:

--report: Output full status in JSON format.
--simple: Output simple status in JSON format. (Note: If no argument is specified, the default behaviour is to output a Healthy or Unhealthy status in plain text.)

Configuration

The URLs to be checked and other configurations are specified in the config.json file. The configuration options are as follows:

urls: A list of URLs to be checked.
timeout: The timeout (in seconds) for each HTTP request.
success_codes: A list of HTTP status codes considered as successful responses.
verify_tls: A boolean value indicating whether TLS verification should be enabled or disabled.

Example config.json:

{
    "urls": [
        "https://google.com",
        "https://apple.com"
    ],
    "timeout": 5,
    "success_codes": [200, 301, 401, 404, 502],
    "verify_tls": true
}

Install Software

sudo apt-get update
sudo apt-get install nginx uwsgi uwsgi-plugin-python3 uwsgi-emperor

Installation of Script

Create the /opt/healthcheck directory
```
mkdir /opt/healthcheck
```

Copy the script and example configuration

cp health_check.py /opt/healthcheck
cp config.json /opt/healthcheck

Set up permissions

chown -R www-data:www-data /opt/healthcheck
chmod 755 /opt/healthcheck/health_check.py
chmod 644 /opt/healthcheck/config.json

Running the Script (Command Line)

To run the script with its default behaviour:

/opt/healthcheck/health_check.py

To get the full status in JSON format:

/opt/healthcheck/health_check.py --report

To get the simple status in JSON format:

/opt/healthcheck/health_check.py --simple

Configure uWSGI Emperor

Copy the health_check.ini uWSGI app configuration

cp health_check.ini /etc/uwsgi-emperor/vassals

Set up permissions

chown root:root /etc/uwsgi-emperor/vassals/health_check.ini
chmod 644 /etc/uwsgi-emperor/vassals/health_check.ini

NGINX Configuration

Below is an NGINX proxy configuration to the uWSGI app:

server {
    listen 80 default_server;

    server_name _;

    location / {
        return 200 '';
        add_header Content-Type text/html;
    }

    location /healthcheck {
        include uwsgi_params;
        uwsgi_pass unix:/opt/healthcheck/health_check.sock;
    }
}

meappy / healthcheck