infra.yml

AWSTemplateFormatVersion: 2010-09-09
Description: Valheim server
Parameters:
  ServerName:
    Type: String
    Description: The public name for your Valheim dedicated server
    Default: "Dedicated Valheim server"
  AMI:
    Type: String
    Description: The Base image for your server, defaults to Amazon AMI eu-west-2
    Default: "ami-0ffd774e02309201f"
  ServerPassword:
    Type: String
    Description: The password for your Valheim dedicated server
  EmailAddress:
    Type: String
    Description: An email address to use for server change notifications. (restarted|updated|crashed|backup)
  S3BucketName:
    Type: String
    Description: The unique name of an S3 bucket to restore and backup to

Resources:
  EC2Instance:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: t2.medium
      IamInstanceProfile: !Ref InstanceProfile
      SecurityGroups:
        - Ref: InstanceSecurityGroup
      ImageId: !Ref AMI
      UserData:
        Fn::Base64: !Sub |
          Content-Type: multipart/mixed; boundary="//"
          MIME-Version: 1.0

          --//
          Content-Type: text/cloud-config; charset="us-ascii"
          MIME-Version: 1.0
          Content-Transfer-Encoding: 7bit
          Content-Disposition: attachment; filename="cloud-config.txt"

          #cloud-config
          cloud_final_modules:
          - [scripts-user, always]

          --//
          Content-Type: text/x-shellscript; charset="us-ascii"
          MIME-Version: 1.0
          Content-Transfer-Encoding: 7bit
          Content-Disposition: attachment; filename="userdata.txt"

          #!/bin/bash

          # Update server and install dependencies
          yum update -y
          yum install epel-release -y
          yum install curl wget tar bzip2 gzip unzip python3 binutils bc jq tmux glibc.i686 libstdc++ libstdc++.i686 -y

          # Create new user to use
          adduser vhserver
          su - vhserver
          cd /home/vhserver

          # Use LinuxGSM automated install
          sudo -u vhserver wget -O linuxgsm.sh https://linuxgsm.sh --output-file=wget_error.log
          sudo -u vhserver chmod +x linuxgsm.sh
          sudo -u vhserver bash linuxgsm.sh vhserver

          # Install Valheim
          sudo -u vhserver /home/vhserver/vhserver auto-install

          # Configure the server with our parameters
          echo 'startparameters="-name '${ServerName}' -password ${ServerPassword} -port 2456 -world '${ServerName}' -public 1"' >> /home/vhserver/lgsm/config-lgsm/vhserver/vhserver.cfg

          # Create cron tasks
          touch /tmp/crontab_template
          touch /tmp/global_crontab_template
          echo 'MAILTO="${EmailAddress}"' >> /tmp/crontab_template
          echo '*/5 * * * * /home/vhserver/vhserver monitor > /dev/null 2>&1' >> /tmp/crontab_template
          echo '*/30 * * * * /home/vhserver/vhserver update > /dev/null 2>&1' >> /tmp/crontab_template
          echo '0 0 * * 0 /home/vhserver/vhserver update-lgsm > /dev/null 2>&1' >> /tmp/crontab_template

          # Setup Automated Half Hourly Backups
          if [[ -z "${S3BucketName}" ]]; then
            echo 'No S3 Bucket Set - Skipping Backup Setup'
          else
            touch /home/vhserver/backup_worlds.sh
            chmod +x /home/vhserver/backup_worlds.sh
            echo '#!/bin/sh' >> /home/vhserver/backup_worlds.sh
            echo '' >> /home/vhserver/backup_worlds.sh
            echo 'aws s3 cp /home/vhserver/.config/unity3d/IronGate/Valheim/worlds s3://${S3BucketName}/vhserver/ --recursive' >> /home/vhserver/backup_worlds.sh
            echo 'MAILTO="${EmailAddress}"' >> /tmp/global_crontab_template
            echo '*/30 * * * * /home/vhserver/backup_worlds.sh > /dev/null 2>&1' >> /tmp/global_crontab_template
          fi

          # Restore Existing Worlds / From Backup
          if [[ -z "${S3BucketName}" ]]; then
            echo 'NO S3 Bucket Set - Skipping Restore Setup'
          else
            aws s3 cp s3://${S3BucketName}/vhserver/ /home/vhserver/.config/unity3d/IronGate/Valheim/worlds --recursive --exclude "*" --include "${ServerName}.*"
          fi

          # Ensure vhserver owns all files and folders
          sudo chown -R vhserver:vhserver /home/vhserver

          # Add cron tasks
          sudo -u vhserver crontab /tmp/crontab_template
          sudo crontab /tmp/global_crontab_template
            
          # Start the server
          sudo -u vhserver /home/vhserver/vhserver start

          # Check everything is working
          sudo -u vhserver /home/vhserver/vhserver monitor

      Tags:
        - Key: Name
          Value: Valheim-EC2Instance

  # Create security rules for the instance
  InstanceSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Valheim inbound and outbound security
      SecurityGroupIngress:
        - Description: Valheim default UDP ports.
          IpProtocol: udp
          FromPort: 2456
          ToPort: 2458
          CidrIp: 0.0.0.0/0
        - Description: SSH traffic
          IpProtocol: tcp
          FromPort: 22
          ToPort: 22
          CidrIp: 0.0.0.0/0
      Tags:
        - Key: Name
          Value: Valheim-EC2SecurityGroup

  # Create and associate an elastic IP to the instance
  ElasticIPAddress:
    DependsOn: EC2Instance
    Type: AWS::EC2::EIP
    Properties:
      InstanceId: !Ref EC2Instance
      Tags:
        - Key: Name
          Value: Valheim-EC2ElasticIPAddress

  # Create a role for the instance
  InstanceRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: Valheim-IAMRole
      Path: /
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/service-role/AmazonEC2RoleforSSM
      AssumeRolePolicyDocument:
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - ec2.amazonaws.com
            Action:
              - sts:AssumeRole
      Policies:
        - PolicyName: DistAccess
          PolicyDocument:
            Statement:
              - Effect: Allow
                Action:
                  - s3:GetObject
                  - s3:PutObject
                Resource:
                  - !Sub arn:aws:s3::*:${S3BucketName}/*
      Tags:
        - Key: Name
          Value: Valheim-IAMRole

  # Create an IAM profile for the instance
  InstanceProfile:
    Type: AWS::IAM::InstanceProfile
    Properties:
      InstanceProfileName: Valheim-IAMInstanceProfile
      Path: /
      Roles:
        - !Ref InstanceRole

Outputs:
  FullServerAddress:
    Description: The full address you can use to connect to your server
    Value: !Sub "${EC2Instance.PublicIp}:2456"