Installing minecraft server on raspberry pi

install_minecraft_on_pi.sh

# This can be replaced with something that identifies the most current java8 version and automatically sets the following
# 3 variables
JAVA8_TARBALL = "jdk-8u171-linux-arm32-vfp-hflt.tar.gz"
JAVA8_URL = "http://download.oracle.com/otn-pub/java/jdk/8u171-b11/512cd62ec5174c3487ac17c61aaa89e8/${JAVA8_TARBALL}"
JDK_PATH = "jdk1.8.0_171"

MINECRAFT_VERSION = "1.13.1"

# connect to pi
ssh pi@minecraftpi

# get and unpack java8
cd /opt
sudo wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" ${JAVA8_URL}
sudo tar -zxvf ${JAVA8_TARBALL}

# Add this new version of java to the java registry
sudo update-alternatives --install /usr/bin/java java /opt/${JDK_PATH}/bin/java 1
sudo update-alternatives --install /usr/bin/javac javac /opt/${JDK_PATH}/bin/javac 1

# select the correct version of java to use (i.e. the on installed in /opt)
sudo update-alternatives --config java
sudo update-alternatives --config javac

# validate the correct version is used by default
java -version
javac -version

# clean up
sudo rm /opt/${JAVA8_TARBALL}

# update and upgrade
sudo apt-get update && sudo apt-get -y upgrade

# install git and screen
sudo apt-get install git
sudo apt-get install screen

# install minecraft
cd ~
mkdir minecraft
cd minecraft
wget https://hub.spigotmc.org/jenkins/job/BuildTools/lastSuccessfulBuild/artifact/target/BuildTools.jar

# build minecraft (NOTE:  This will take upwards of an hour)
sudo java -jar BuildTools.jar --rev ${MINECRAFT_VERSION}

# run and configure Spigot Minecraft server
sudo java -Xms512M -Xmx1008M -jar /home/pi/minecraft/spigot-${MINECRAFT_VERSION}.jar nogui

# stop the server, edit the EULA, changing 'eula=true'
sudo nano eula.txt

# download and replace the server.properties file
wget https://www.linuxnorth.org/minecraft/server.properties

# Install the RaspberryJuice plugin to activate the Minecraft API
wget -O ~/minecraft/plugins/RaspberryJuice.jar https://dev.bukkit.org/projects/raspberryjuice/files/latest

# run the server a second time to build the initial world
sudo java -Xms512M -Xmx1008M -jar /home/pi/minecraft/spigot-${MINECRAFT_VERSION}.jar nogui

References:

• https://www.r-bloggers.com/a-maze-solving-minecraft-robot-in-r/
• https://www.linuxnorth.org/minecraft/

Finally, edit/create /home/pi/startup/minecraft.sh:

if ! screen -list | grep -q "minecraft"; then
  cd /home/pi/minecraft && java -jar  -Xms512M -Xmx1008M spigot-${MINECRAFT_VERSION}.jar nogui
fi

And, to auto launch on boot, edit /etc/rc.local, adding before exit 0:

screen -S minecraft -d -m /home/pi/startup/minecraft.sh