#!/usr/bin/env bash
# install-prometheus.sh
# Prometheus — Pull-based metrics collection, storage, and alerting.
# Target: Ubuntu / Debian. Safe to re-run.
# Source guide: devops-hub/tools/prometheus.html

set -euo pipefail

if [[ $EUID -eq 0 ]]; then
  echo "Run this as a regular sudo-capable user, not root." >&2
  exit 1
fi

echo "==> Create a system user"
sudo useradd --no-create-home --shell /bin/false prometheus

echo "==> Download and extract the release"
curl -LO https://github.com/prometheus/prometheus/releases/latest/download/prometheus-linux-amd64.tar.gz
tar xvf prometheus-linux-amd64.tar.gz

echo "==> Install binaries and config"
sudo mv prometheus-*/prometheus prometheus-*/promtool /usr/local/bin/
sudo mkdir -p /etc/prometheus /var/lib/prometheus
sudo mv prometheus-*/consoles prometheus-*/console_libraries /etc/prometheus/

echo "==> Run it"
prometheus --config.file=/etc/prometheus/prometheus.yml

echo "==> Done. Prometheus installation finished."