stack

#!/bin/bash

#set -ex

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

DEPLOYMENT_DIR=${SCRIPT_DIR}/deployments
IMAGE="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 "  dev\t\tDevelop the service. Port defaults to 8080.\n"
	printf "  \t\tSyntax: dev [action]\n"
	printf "  \t\tExample: dev up\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 "  install\tInstall dependencies.\n"
	printf "  \t\tSyntax: install\n"
	printf "  \t\tExample: install\n"
	printf "\n"
	printf "  logs\t\tSee logs.\n"
	printf "  \t\tSyntax: logs\n"
	printf "  \t\tExample: logs\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 "  up | down\tDeploy or destroy the stack. Tag defaults to 'latest'.\n"
	printf "  \t\tSyntax: up [<tag>]\n"
	printf "  \t\tExample: up v0.1.0\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."
}

install_if_doesnt_exist(){
	local tool=$1
	local cmd=$2
	type $tool > /dev/null 2>&1
	if [[ "$?" == "1" ]]; then
		printf "Installing ${tool} ...\n"
		echo "$cmd" | /bin/bash
	else
		printf "${tool} is already installed.\n"
	fi
}

install_tools() {
	KUBECTL_VERSION=${KUBECTL_VERSION:-v1.28.4}
	MINIKUBE_VERSION=${MINIKUBE_VERSION:-v1.31.1}
	echo $KUBECTL_VERSION
	install_if_doesnt_exist "kubectl" "curl -LO https://dl.k8s.io/release/${KUBECTL_VERSION}/bin/$(uname -s | tr 'A-Z' 'a-z')/$(uname -m)/kubectl && chmod +x ./kubectl && sudo mv ./kubectl /usr/local/bin/kubectl"
	install_if_doesnt_exist "minikube" "curl -Lo minikube https://storage.googleapis.com/minikube/releases/v1.31.1/minikube-$(uname -s | tr 'A-Z' 'a-z')-$(uname -m) && chmod +x minikube && sudo cp minikube /usr/local/bin/ && rm minikube"
	install_if_doesnt_exist "kubetpl" "curl -sSL https://github.com/shyiko/kubetpl/releases/download/0.9.0/kubetpl-0.9.0-$(bash -c '[[ $OSTYPE == darwin* ]] && echo darwin || echo linux')-amd64 -o kubetpl && chmod a+x kubetpl && sudo mv kubetpl /usr/local/bin/"
}

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}
}

develop() {
	local action="$1"

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

	if [[ "$action" == "up" ]]; then
		tilt up
	elif [[ "$action" == "down" ]]; then
		tilt down
	fi
}

deploy_or_destroy_stack() {
	local action="$1"
	local target_env="$2"
	local tag=${3:-latest}

	validate_empty_input "$action" "Error: action (e.g. up, down) can't be empty."
	validate_empty_input "$target_env" "Error: target environmnet (e.g. local, dev, etc.) can't be empty."

	if [[ "$action" == "up" ]]; then
		kubetpl render ${DEPLOYMENT_DIR}/app.yaml -i ${DEPLOYMENT_DIR}/config-${target_env}.env -s IMAGE_TAG=$tag | kubectl apply -f -
		kubectl get pods
	elif [[ "$action" == "down" ]]; then
		kubetpl render ${DEPLOYMENT_DIR}/app.yaml -i ${DEPLOYMENT_DIR}/config-${target_env}.env -s IMAGE_TAG=$tag | kubectl delete -f -
	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}"
		;;
	dev)
		develop "${@:2}"
		;;
	expose)
		expose_service "${@:2}"
		;;
	install)
		install_tools "${@:2}"
		;;
	logs)
		print_logs
		;;
	push)
		push_images "${@:2}"
		;;
	up | down)
		deploy_or_destroy_stack "${@:1}"
		;;
	* | -h | help)
		usage
		;;
esac