base.json

{
  "variables": {
  },
  "builders": [
    {
      "type" : "amazon-ebs",
      "ami_name": "chromium-builder.{{timestamp}}",
      "region" : "us-east-2",
      "instance_type" : "c5.xlarge",
      "spot_price": "0.1",
      "block_duration_minutes": 60,
      "source_ami_filter": {
        "most_recent": true,
        "filters": {
          "name": "ubuntu/images/hvm-ssd/ubuntu-bionic-18.04-amd64-server-*",
          "virtualization-type": "hvm",
          "root-device-type": "ebs"
        },
        "owners": ["099720109477"]
      },
      "launch_block_device_mappings": [
        {
          "device_name": "/dev/sda1",
          "volume_size": 40,
          "volume_type": "gp2",
          "delete_on_termination": true
        }
      ],
      "ssh_username" : "ubuntu"
    }
  ],
  "provisioners": [
    {
      "type": "shell",
      "inline": [
        "while ! systemctl is-active cloud-init.target; do sleep 1; done"
      ]
    },
    {
      "type": "shell",
      "scripts": [
        "scripts/prepare.sh"
      ]
    }
  ]
}