kubectl wrapper

kubektl

#!/usr/bin/env bash

#
# WHAT
#
# kubektl - interactive kubectl wrapper
#
# Dixit "Claude Snonnet 4" -- This is a well-designed utility that significantly improves the developer experience
# when working with Kubernetes clusters, especially in environments with many contexts, namespaces, and resources!
#
# INSTALLATION
#
# ln -s ${PWD}/kubektl $(brew --prefix)/bin/
# sudo ln -s ${PWD}/kubektl /usr/local/bin/
#
# PREREQUISITES
#
# brew install fzf
# brew install lolcat
#

# define the cache directory
export cache_home=${XDG_CACHE_HOME:-$HOME/.cache}/kubektl ;

# view the cache directory
# lsd --tree ${XDG_CACHE_HOME:-$HOME/.cache}/kubektl/ ;

# clear the cache directory
# rm -rf ${XDG_CACHE_HOME:-$HOME/.cache}/kubektl/* ;

# by default do not refresh the cache
refresh_cache=false ;

# detect the optional --refresh clarg
if [[ "$1" = "--refresh" ]] ; then
	# set the refresh_cache flag
	refresh_cache=true ;
	# remove --refresh from arguments
	shift ;
fi

set -e ; # CTRL-C or ESC (empty selection) in fzf will exit the script

select_from_list() {
	label=$(echo "Select a ${1:-item} ..."|lolcat -f) ;
	fzf --height="~100%" --border --border-label-pos=5:top --border-label="> ${label} <" ;
}

select_from_list_or_exit() {
	selected_item=$(select_from_list "${1:-item}") ;
	if [[ -z "${selected_item}" ]] ; then
		> /dev/tty echo "No ${1:-item} selected, aborting!" ;
		/usr/bin/env false ;
	else
		highlighted_item=$(echo "\"${selected_item}\"" | lolcat -f) ;
		> /dev/tty printf "Selected ${1:-item}: %s\n" "${highlighted_item}" ;
		echo "${selected_item}" ;
	fi
}

export kube_context="";
export kube_namespace="";
export kube_pod="";
export pod_container="";

context() {
	[[ -z "${kube_context}" ]] && kube_context=$(
		cache_dir="${cache_home}" ;
		cache_file="${cache_dir}/kube_contexts.txt" ;
		[[ "${refresh_cache}" == "true" ]] && rm -f "${cache_file}" ;
		[[ -f "${cache_file}" ]] || (
			mkdir -p "${cache_dir}" ;
			command kubectl config view | \
			yq '.contexts[].name' \
			> "${cache_file}" ;
		) ;
		< "${cache_file}" select_from_list_or_exit 'kube context' ;
	) ;
	echo "${kube_context}" ;
}

namespace() {
	> /dev/null context ; # prime the kube context

	[[ -z "${kube_namespace}" ]] && kube_namespace=$(
		cache_dir="${cache_home}/${kube_context}" ;
		cache_file="${cache_dir}/kube_namespaces.txt" ;
		[[ "${refresh_cache}" == "true" ]] && rm -f "${cache_file}" ;
		[[ -f "${cache_file}" ]] || (
			mkdir -p "${cache_dir}" ;
			command kubectl --output=json --context "$(context)" get namespaces | \
			jq -r '.items[].metadata.name' \
			> "${cache_file}" ;
			# jq -r '.items[] | select(.status.phase=="Active") | .metadata.name'
		) ;
		< "${cache_file}" select_from_list_or_exit 'kube namespace' ;
	) ;
	echo "${kube_namespace}" ;
}

pod() {
	> /dev/null namespace ; # prime the kube namespace (and context)

	[[ -z "${kube_pod}" ]] && kube_pod=$(
		cache_dir="${cache_home}/${kube_context}/${kube_namespace}" ;
		cache_file="${cache_dir}/kube_pods.txt" ;
		[[ "${refresh_cache}" == "true" ]] && rm -f "${cache_file}" ;
		[[ -f "${cache_file}" ]] || (
			mkdir -p "${cache_dir}" ;
			command kubectl --output=json --context "$(context)" --namespace "$(namespace)" get pods | \
			jq -r '.items[]|.metadata.name' \
			> "${cache_file}" ;
			# jq -r '.items[] | select(.status.phase=="Running") | .metadata.name'
		)
		< "${cache_file}" select_from_list_or_exit 'kube pod' ;
	) ;
	echo "${kube_pod}" ;
}

container() {
	> /dev/null pod ; # prime the kube pod (and namespace, and context)

	[[ -z "${pod_container}" ]] && pod_container=$(
		cache_dir="${cache_home}/${kube_context}/${kube_namespace}/${kube_pod}" ;
		cache_file="${cache_dir}/pod_containers.txt" ;
		[[ "${refresh_cache}" == "true" ]] && rm -f "${cache_file}" ;
		[[ -f "${cache_file}" ]] || (
			mkdir -p "${cache_dir}" ;
			command kubectl --output=json --context "$(context)" --namespace "$(namespace)" get pods "$(pod)" | \
			jq -r '.spec.containers[].name' \
			> "${cache_file}" ;
		)
		< "${cache_file}" select_from_list_or_exit 'pod container' ;
	) ;
	echo "${pod_container}" ;
}

kubectl_cmd="$1" ; shift ;

case "${kubectl_cmd}" in
	"exec")
		> /dev/null container ; # prime the pod container

		[[ $# -eq 0 ]] && (
		command kubectl --context "$(context)" exec -it --namespace "$(namespace)" "$(pod)" --container "$(container)" -- /bin/sh ;
		)
		[[ $# -ne 0 ]] && (
		command kubectl --context "$(context)" exec -it --namespace "$(namespace)" "$(pod)" --container "$(container)" -- /bin/sh -c "$*" ;
		)

		;;
	"logs")
		> /dev/null container ; # prime the pod container

		command kubectl --context "$(context)" logs "$@" --namespace "$(namespace)" "$(pod)" --container "$(container)" ;

		;;
	"pods")
		> /dev/null namespace ; # prime the kube namespace

		command kubectl --context "$(context)" get pods -o wide --namespace "$(namespace)" ;

		;;
	"port-forward")
		> /dev/null pod ; # prime the kube pod

		command kubectl --context "$(context)" --namespace "$(namespace)" port-forward pod/"$(pod)" "$@" ;

		;;
	"delete")
		> /dev/null pod ; # prime the kube pod

		command kubectl --context "$(context)" delete pod --namespace "$(namespace)" "$(pod)" --now --interactive ;

		;;
	*)
		> /dev/null context ; # prime the kube context

		command kubectl --context "$(context)" "$@" ;

		;;
esac

# That's all Folks!