How to make Docker Hub rate limit monitoring a breeze

What this post added

This post introduces a Python script (`check_docker_hub_limit.py`) and a Prometheus exporter (`docker-hub-limit-exporter`) to monitor Docker Hub rate limits. The script allows users to check the current limit and remaining pull requests, set warning and critical thresholds, and provides performance metrics. The Prometheus exporter exposes these metrics via an HTTP endpoint for scraping by Prometheus, with a demo environment including Grafana for visualization. The post also references existing GitLab blog posts on mitigating Docker Hub rate limits and using the Dependency Proxy.