GitHub - bjarneo/uptime-cron-alerts: Poor man's uptime alerts

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Service Health Check Script

This Bash script checks the health of specified services and sends notifications to Slack if any service is not responding with a 200 OK status.

Note: This is as basic as it gets

Features

  • Checks the health of multiple services
  • Sends Slack notifications when a service goes down or comes back up
  • Runs checks in parallel for efficiency
  • Maintains service status in a JSON file to track changes

How it works

  1. The script iterates through the list of services.
  2. For each service, it sends a GET request and checks the HTTP status code.
  3. If a service is down (non-200 response) and was previously up, it sends a Slack notification.
  4. If a service is up (200 response) and was previously down, it sends a Slack notification.
  5. The current status of each service is stored in a JSON file (service_status.json).

Prerequisites

  • Bash shell
  • curl command-line tool
  • Slack webhook URL
  • jq command-line JSON processor

Configuration

  1. Edit the services array to include the URLs of the services you want to monitor.
  2. Set the slack_webhook variable with your Slack webhook URL.

Usage

  1. Make the script executable:

  2. Run the script:

It's recommended to set up a cron job to run this script at regular intervals.

Running with Cron

To run this script every minute using cron:

  1. Open the crontab file:

  2. Add the following line to run the script every minute:

    * * * * * /path/to/uptime.sh

    Replace /path/to/ with the actual path to your script.

  3. Save and exit the crontab editor.

The script will now run automatically every minute.

Customization

  • Add more services to the services array as needed.
  • Modify the check_service function to adjust the health check criteria or add more complex checks.

Note

Please ensure the Slack webhook URL is kept confidential and not shared publicly.