packer_custom.json

{
  "variables": {
    "vpc_region": "eu-west-1",
    "ssh_username": "ubuntu",
    "vpc_id":  "{{env `VPC_ID`}}",
    "subnet_id": "{{env `SUBNET_ID`}}"
  },
  "builders": [
    {
      "type": "amazon-ebs",
      "name": "ubuntu-20.04-custom",
      "vpc_id":  "{{user `vpc_id`}}",
      "subnet_id": "{{user `subnet_id`}}",
      "region": "{{user `vpc_region`}}",
      "source_ami_filter": {
        "filters": {
          "virtualization-type": "hvm",
          "name": "ubuntu/images/*ubuntu-focal-20.04-amd64-server-*",
          "root-device-type": "ebs"
        },
        "owners": ["099720109477"],
        "most_recent": true
      },
      "instance_type": "m5a.large",
      "ssh_username": "{{user `ssh_username`}}",
      "ami_name": "jenkins-custom-amd64-{{isotime \"2006-01-02-1504\"}}",
      "ami_regions": ["eu-west-1" ],
      "launch_block_device_mappings": [
        {
          "device_name": "/dev/sda1",
          "volume_type": "gp2",
          "volume_size": "80",
          "delete_on_termination": true
        }
      ],
      "run_tags": {
        "Name": "packer_builder"
      }
    }
  ],
  "provisioners": [
    {
      "type": "shell",
      "inline": [ "sleep 60" ]
    },
    {
      "type": "shell",
      "script": "custom.sh",
      "execute_command": "{{.Vars}} sudo -E sh -eux '{{.Path}}'"
    }
  ]
}