stack

#!/bin/bash

#set -ex

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"

DEPLOYMENT_DIR=${SCRIPT_DIR}/deployments
IMAGE="airbusutm/hello-spring"

usage() {
	printf "Usage:\n"
	printf "  help\t\tShow this help\n"
	printf "\n"
	printf "  build\t\tBuild the stack. Tag defaults to 'latest'.\n"
	printf "  \t\tSyntax: build [<tag>]\n"
	printf "  \t\tExample: build e0daeddc1f1f39f1f305e4cc5c4db6a247d05123\n"
	printf "\n"
	printf "  expose\tExpose the service. Port defaults to 8080.\n"
	printf "  \t\tSyntax: expose [<port>]\n"
	printf "  \t\tExample: expose\n"
	printf "\n"
	printf "  push\t\tPush containers to registry. Tag defaults to 'latest'\n"
	printf "  \t\tSyntax: push [<tag>]\n"
	printf "  \t\tExample: push e0daeddc1f1f39f1f305e4cc5c4db6a247d05123\n"
	printf "\n"
	printf "  logs\t\tSee logs.\n"
	printf "  \t\tSyntax: logs\n"
	printf "  \t\tExample: logs\n"
	printf "\n"
	printf "  up | down\tDeploy or destroy the stack. Tag defaults to 'latest'.\n"
	printf "  \t\tSyntax: up [<tag>]\n"
	printf "  \t\tExample: up e0daeddc1f1f39f1f305e4cc5c4db6a247d05123\n"
	printf "\n"
}

validate_empty_input() {
	local user_input="$1"
	local err_msg="$2"

	[[ -z "$user_input" ]] && printf "$err_msg\n" && exit 1
}

validate_target_env() {
	local target_env="$1"
	validate_empty_input "$target_env" "Error: target environment (allowed values: local, remote) can't be empty."
}

build_stack() {
	local tag=${1:-latest}

	# Cleanup old jars
	rm -rf target/*-SNAPSHOT.jar
	docker run --rm -v $PWD:/src -w /src maven:3.8-openjdk-18-slim /bin/bash -c "mvn clean install"
	docker build --platform=linux/amd64 -t ${IMAGE}:${tag} -f Dockerfile .
}

push_images() {
	local tag=${1:-latest}

	docker push ${IMAGE}:${tag}
}

deploy_or_destroy_stack() {
	local action="$1"

	validate_empty_input "$action" "Error: action (e.g. up, down) can't be empty."

	if [[ "$action" == "up" ]]; then
		kubectl apply -f ${DEPLOYMENT_DIR}/
		kubectl get pods
	elif [[ "$action" == "down" ]]; then
		kubectl delete -f ${DEPLOYMENT_DIR}/
	fi
}

expose_service(){
	local port="${1-:${CONTAINER_PORT}}"

	kubectl port-forward deployments/greetings ${port}:8080
}

print_logs() {
	kubectl logs -f deployment/greetings
}

case "$1" in
	build)
		build_stack "${@:2}"
		;;
	expose)
		expose_service "${@:2}"
		;;
	push)
		push_images "${@:2}"
		;;
	logs)
		print_logs
		;;
	up | down)
		deploy_or_destroy_stack "${@:1}"
		;;
	* | -h | help)
		usage
		;;
esac