Host a Minecraft - Java Edition (Velocity) Dedicated Server

# Update system and install Docker
sudo apt update && sudo apt install -y docker.io
sudo systemctl enable --now docker

# Create game server directory
sudo mkdir -p /opt/gameserver

# Server configuration
export PLAYER_INFO_FORWARDING="modern"
export ONLINE_MODE="true"

# Pull the container image
docker pull eclipse-temurin:21-jre-alpine

#!/bin/bash

apt update
apt install -y wget curl jq

cd /opt/gameserver || { echo "Failed to change directory to /opt/gameserver"; exit 1; }

# Resolve Velocity version
VEL_VERSION="${VELOCITY_VERSION:-latest}"
VELOCITY_API="https://api.papermc.io/v2/projects/velocity"

if [ "$VEL_VERSION" = "latest" ]; then
  echo "Fetching latest Velocity version..."
  VEL_VERSION=$(curl -sSL "$VELOCITY_API" | jq -r '.versions[-1]')
  echo "Latest Velocity version: $VEL_VERSION"
else
  echo "Using specified version: $VEL_VERSION"
fi

# Verify version exists
VER_CHECK=$(curl -sSL "$VELOCITY_API" | jq -r --arg V "$VEL_VERSION" '.versions[] | select(. == $V)')
if [ -z "$VER_CHECK" ]; then
  echo "WARNING: Version $VEL_VERSION not found. Falling back to latest..."
  VEL_VERSION=$(curl -sSL "$VELOCITY_API" | jq -r '.versions[-1]')
fi

# Get latest build
echo "Fetching latest Velocity build for $VEL_VERSION..."
BUILD_INFO=$(curl -sSL "$VELOCITY_API/versions/$VEL_VERSION/builds")
LATEST_BUILD=$(echo "$BUILD_INFO" | jq -r '.builds[-1].build')
JAR_NAME=$(echo "$BUILD_INFO" | jq -r '.builds[-1].downloads.application.name')

if [ -z "$LATEST_BUILD" ] || [ "$LATEST_BUILD" = "null" ]; then
  echo "ERROR: Could not determine latest build for Velocity $VEL_VERSION!"
  exit 1
fi

DOWNLOAD_URL="$VELOCITY_API/versions/$VEL_VERSION/builds/$LATEST_BUILD/downloads/$JAR_NAME"
echo "Downloading Velocity $VEL_VERSION build $LATEST_BUILD..."
wget -q "$DOWNLOAD_URL" -O velocity.jar
echo "Velocity download completed."

# Generate forwarding secret if it doesn't exist
if [ ! -f forwarding.secret ]; then
  echo "Generating forwarding secret..."
  date +%s | sha256sum | base64 | head -c 24 > forwarding.secret
  echo "Forwarding secret created."
else
  echo "Forwarding secret already exists, keeping it."
fi

echo "Install Completed"

sudo ufw allow 25565/tcp