start.sh

#!/usr/bin/env bash

set -o pipefail;
set -o errexit;
set -o errtrace;
set -o nounset;

_main_src_dir="$(dirname "$(readlink -f "$0")")";
_jdk_dir="$_main_src_dir/jdk";
_jdk_link='https://github.com/AdoptOpenJDK/openjdk16-binaries/releases/download/jdk-16.0.1%2B9/OpenJDK16U-jdk_x64_linux_hotspot_16.0.1_9.tar.gz';
_paper_jar="$_main_src_dir/paper.jar";
_ngrok_bin="$_main_src_dir/ngrok";
_cloudflared_bin="$_main_src_dir/cloudflared";
_paper_jar_link="https://papermc.io/api/v2/projects/paper/versions/1.16.5/builds/783/downloads/paper-1.16.5-783.jar"
_arg_mem="${ALLOC_MEM:-"1G"}";

if test ! -e "$_paper_jar"; then
	echo '------- Downloading paper server'
	curl -L "$_paper_jar_link" -o "$_paper_jar";
fi

if test ! -e "$_jdk_dir"; then
	echo '------- Downloading JDK'
	mkdir -p "$_jdk_dir";
	curl -L "$_jdk_link" | tar --strip-components=1 -C "$_jdk_dir" -xpzf -;
fi

if test "${TUNNEL:-ngrok}" == ngrok; then {
	if test ! -e "$_ngrok_bin"; then
		echo '------ Downloading ngrok';
		_ngrok_dw_link="https://bin.equinox.io/c/4VmDzA7iaHb/ngrok-stable-linux-amd64.zip";
		curl -L "$_ngrok_dw_link" -o "$_main_src_dir/ngrok.zip";
		unzip -p "$_main_src_dir/ngrok.zip" ngrok > "$_ngrok_bin";
		rm "$_main_src_dir/ngrok.zip";
	fi
	chmod +x "$_ngrok_bin";
	if test -z "${1:-}"; then {
		echo '------ ERROR: Ngrok authtoken not provided';
		exit 1;
	} fi
	"$_ngrok_bin" authtoken "${1}";
	"$_ngrok_bin" tcp --log "stdout" 25565 > "$_main_src_dir/ngrok.log" 2>&1 &

	echo '------- Fetching address for sharing....'
	while true; do {
		if _fetch="$(grep 'url=.*ngrok\.io.*' "$_main_src_dir/ngrok.log")"; then {
			echo -e "\n-------------------------------------------------"
			echo "+++ Server address for sharing: $(awk -F 'url=tcp://' '{print $2}' <<<"$_fetch")";
			echo -e "-------------------------------------------------\n"
			break;
		} else {
			sleep 1;
		} fi
	} done
} else {
	if test ! -e "$_cloudflared_bin"; then {
		echo '------- Downloading Cloudflared';
		_cloudflared_dw_link="https://github.com/cloudflare/cloudflared/releases/download/2021.8.2/cloudflared-linux-amd64";
		curl -L "$_cloudflared_dw_link" -o "$_cloudflared_bin";
	} fi

	pkill -9 cloudflared || true;
	chmod +x "$_cloudflared_bin";
	"$_cloudflared_bin" tunnel --url tcp://127.0.0.1:25565 > "$_main_src_dir/cloudflared.log" 2>&1 &
	echo '------- Fetching address for sharing....'
	while true; do {
		if _fetch="$(grep -o -m1 'https://.*.trycloudflare.com' "$_main_src_dir/cloudflared.log")"; then {
			echo -e "\n-------------------------------------------------"
			echo "+++ Server address for sharing: $_fetch";
			echo '+++ Note: It can take 1-2 minutes to propagate for everyone';
			echo '+++ Note: Your firends can not connect to it directly, they have to connect via cloudflared first, check README.md';
			echo -e "-------------------------------------------------\n"
			break;
		} else {
			sleep 1;
		} fi
	} done
} fi

echo '------- Starting the server...'
export PATH="$_jdk_dir/bin:$PATH";
java -Xms${_arg_mem} -Xmx${_arg_mem} -jar "$_paper_jar" --nogui;