tonisanta / monitoring-service

Background task to check the status of a given url. Exposes metrics using Prometheus to keep track of the evolution

Monitoring service

This background task checks the status of a given URL. If the request takes longer than a specific timeout, is cancelled (and it's considered as a 499 status code).

For every request, we store some Prometheus metrics that will be helpful to create a dashboard to visualize the status and the evolution of the system. Metrics are exposed in http://localhost:port/metrics, port can be adjusted with --port=8080

Run commands

Additionally, the server exposes the /exec endpoint that allows running any command. Once the command has been executed, creates a new annotation in the Grafana, this way you can track the evolution since that specific moment (in this dashboard we use a dashed blue line).

For example, we can see that the response time decreases after a restart of a specific service in our docker-compose.

Example request - POST http://localhost:port/exec

{
    "command": "docker compose restart"
}

Configuration

Flag	Default	Description
url	https://google.com/	Url to monitor
token	Non valid token	Grafana API token
host	http://localhost:3000	Grafana host
frequency	1m	Status check frequency
timeout	30s	Request timeout
port	8080	Port used by the server