minecraft_server.sh

#!/bin/bash

printf "\033c"

if [ "$(id -u)" != "0" ]; then
	echo -e "\n---------------------------------------------------------------------------------\n"
	echo -e "PLEASE EXECUTE THIS SCRIPT AS ROOT OR SUDO!\n"
	echo "sudo ${0}"
	echo -e "\n---------------------------------------------------------------------------------"
	exit 1
fi

DEPENDENCIES="ca-certificates screen default-jre-headless wget host"
dpkg -s $DEPENDENCIES &>/dev/null
if [ $? -ne 0 ]; then
	echo -e "For Minecraft to work we need to install the following dependencies:\n"
	for DEPENDENCY in $DEPENDENCIES; do
		echo "- $DEPENDENCY"
	done
	echo ""
	read -r -p "Please insert 'YES' to allow the installation. Otherwise this script will exit here: " ANSWER
	if [ "$ANSWER" == "YES" ]; then
		apt-get update
		apt-get -y install $DEPENDENCIES
		if [ $? -ne 0 ]; then
			echo -e "\n---------------------------------------------------------------------------------\n"
			echo "Installation failed, trying to fix..."
			echo -e "\n---------------------------------------------------------------------------------\n"
			sleep 3
			apt-get -f -y install
			if [ $? -ne 0 ]; then
				echo "Could not install dependencies. Will exit now."
				exit 1
			fi
		fi
	else
		echo "Your answer was \"$ANSWER\" and not YES. So this script will exit now."
		exit 1
	fi
fi

USERNAME=""
while [ -z "$USERNAME" ] || [ "$USERNAME" == "root" ]; do
	echo -e "---------------------------------------------------------------------------------\n"
	echo "Please insert your desired username that is used to manage the Minecraft server."
	echo -e "The server will get created in the home directory of the user entered.\n"
	read -r -p "The user gets created if it does not already exist: " USERNAME
done


id -g $USERNAME &>/dev/null
if [ $? -ne 0 ]; then
        groupadd "$USERNAME"
fi

id -u $USERNAME &>/dev/null
if [ $? -ne 0 ]; then
	echo -e "\n---------------------------------------------------------------------------------\n"
	echo "User does not exist! To create this user, we need a password!"
	echo -e "\n---------------------------------------------------------------------------------\n"
	PASSWORD=""
	while [ -z "$PASSWORD" ]; do
        	read -r -s -p "Please insert the desired password for User $USERNAME: " PASSWORD
	done
        useradd -g "$USERNAME" -d /home/"$USERNAME" -m -s /bin/bash -p $(echo "$PASSWORD" | openssl passwd -1 -stdin) "$USERNAME"
fi

echo -e "\n---------------------------------------------------------------------------------\n"

echo -e "What Software should the server run on?\n"
echo "[1] VANILLA"
echo "[2] SPIGOT"
echo "[3] CRAFTBUKKIT"
echo "[4] PAPERSPIGOT"

echo ""

CASE=1
while [ $CASE -ne 0 ]; do
	read -r -p "Please enter the number of your choice: " TYPE_INT
	case $TYPE_INT in
		1)
		TYPE="minecraft_server"
		CASE=0
		;;
		2)
		TYPE="spigot"
		CASE=0
		;;
		3)
		TYPE="craftbukkit"
		CASE=0
		;;
		4)
		TYPE="paperspigot"
		CASE=0
		;;
	esac
done

echo "Which version would you like to use?"
read -r -p "Please enter the version of your choice [ 1.8.8 / 1.12.2 / 1.15.2 ]: " VERSION

echo -e "\n---------------------------------------------------------------------------------\n"
echo "Your server is getting created... Please wait..."
echo -e "\n---------------------------------------------------------------------------------\n"

rm -f /home/"$USERNAME"/*.jar

wget -q https://minecraft-mirror.io/"$TYPE"-"$VERSION".jar -O /home/"$USERNAME"/"$TYPE"-"$VERSION".jar
echo "eula=true" > /home/"$USERNAME"/eula.txt

cat > /home/"$USERNAME"/start.sh << EOF
#!/bin/bash

screen -S minecraft java -jar $TYPE-$VERSION.jar nogui

EOF

chmod +x /home/"$USERNAME"/start.sh
chown -R "$USERNAME":"$USERNAME" /home/"$USERNAME"

echo -e "\n---------------------------------------------------------------------------------"
echo "---------------------------------------------------------------------------------"
echo -e "---------------------------------------------------------------------------------\n"
echo "SETUP COMPLETED SUCCESSFULLY"

echo -e "\n---------------------------------------------------------------------------------"
echo "---------------------------------------------------------------------------------"
echo -e "---------------------------------------------------------------------------------\n"

PASSWORD_OUTPUT=${PASSWORD:=Password for the user was not created with this script, so it existed before.}

echo "Please connect via SSH (e.g. with Putty or another SSH client) using the following credentials:"
echo -e "\n---------------------------------------------------------------------------------\n"

echo "- Username: $USERNAME"
echo "- Password: $PASSWORD_OUTPUT"

echo -e "\n---------------------------------------------------------------------------------\n"

echo "Then execute this command and the server will start:"
echo -e "\n---------------------------------------------------------------------------------\n"

echo "cd /home/"$USERNAME" && ./start.sh"

echo -e "\n---------------------------------------------------------------------------------\n"

IP=$(host myip.opendns.com resolver1.opendns.com | grep "myip.opendns.com has address" | awk '{ print $NF }')

echo "Enter this address into your minecraft client and connect to the server:"
echo -e "\n---------------------------------------------------------------------------------\n"

echo "$IP:25565"

echo -e "\n---------------------------------------------------------------------------------\n"