#!/usr/bin/env bash

set -e

NODE_EXPORTER_VERSION=0.14.0

BASE_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# Download and install Prometheus Node Exporter
ARM_VERSION=v7
if $(uname -m | grep -Eq ^armv6); then
    ARM_VERSION=v6
elif ! [ -z $(uname -m | grep aarch64)]; then
    ARM_VERSION=64
fi
mkdir "$BASE_DIR/tmp"
wget "https://github.com/prometheus/node_exporter/releases/download/v${NODE_EXPORTER_VERSION}/node_exporter-${NODE_EXPORTER_VERSION}.linux-arm${ARM_VERSION}.tar.gz" -O "$BASE_DIR/tmp/node_exporter.tar.gz"
tar xvfz "$BASE_DIR/tmp/node_exporter.tar.gz" -C "$BASE_DIR/tmp" --strip 1
sudo cp "$BASE_DIR/tmp/node_exporter" /usr/local/bin/node_exporter
sudo chown root:staff /usr/local/bin/node_exporter
rm -rf "$BASE_DIR/tmp"

# Configure systemd to start prometheus-node-exporter.service on system boot
sudo cp "$BASE_DIR/prometheus-node-exporter.service" /lib/systemd/system/prometheus-node-exporter.service
sudo systemctl daemon-reload
sudo systemctl enable prometheus-node-exporter.service
sudo systemctl start prometheus-node-exporter.service
