Get Kubernetes CPU and Memory requested

k8s-cpumem-reqlim.sh

#!/bin/bash -eu
#
# Get Kubernetes CPU and memory requested
#

main() {
	declare kubeconfig=$1
	declare node_match="${2:-""}"

	if [[ ! -f $kubeconfig ]]; then
		echo 2> "kubeconfig $kubeconfig not found"
		exit 1
	fi

	local node_count=0
	local total_percent_cpu=0
	local total_percent_mem=0
	local kubectl="kubectl --kubeconfig $kubeconfig"
	local nodes=$($kubectl get nodes --no-headers -o custom-columns=NAME:.metadata.name)
	local comma=""

	echo '{"nodes": ['
	for node in $nodes; do

		local requests=$($kubectl describe node $node | grep -A2 -E "^\\s*CPU Requests" | tail -n1)
		local value_cpu=$(echo $requests | awk -F "[()%]" '{print $1}')
		local percent_cpu=$(echo $requests | awk -F "[()%]" '{print $2}')
		local value_mem=$(echo $requests | awk -F "[()%]" '{print $7}')
		local percent_mem=$(echo $requests | awk -F "[()%]" '{print $8}')
		
		echo $comma'
		{
			"node": "'${node}'",
			"value_cpu": "'${value_cpu}'",
			"percent_cpu": "'${percent_cpu}'",
			"value_mem": "'${value_mem}'",
			"percent_mem": "'${percent_mem}'"
		}'
		comma=,

		if [[ ! "$node" =~ "$node_match" ]]; then
			continue
		fi

		node_count=$((node_count + 1))
		total_percent_cpu=$((total_percent_cpu + percent_cpu))
		total_percent_mem=$((total_percent_mem + percent_mem))
	
	done
	echo ']'

	if [[ $node_count != 0 ]]; then

		local avg_percent_cpu=$((total_percent_cpu / node_count))
		local avg_percent_mem=$((total_percent_mem / node_count))

		echo ',
			"avg": {
				"percent_cpu": "'${avg_percent_cpu}'",
				"percent_mem": "'${avg_percent_mem}'",
				"node_count": "'${node_count}'",
				"node_match": "'${node_match}'"
			}'
	fi
	
	echo '}'
}

main "$@"