Taskfile.yml

# https://taskfile.dev

version: "2"

vars:
  config_path: ./ubuntu-18.04.json

  # Configure your var paths here with the `-var-file="./path/file.json" flag`
  # or any other packer options you need to pass into commands
  packer_args: '-var-file="./config.json"'

  ubuntu_18_04_iso_name: ubuntu-18.04.4-server-amd64.iso
  ubuntu_18_04_iso_url: http://cdimage.ubuntu.com/releases/18.04/release/ubuntu-18.04.4-server-amd64.iso

tasks:
  init:
    cmds:
      - cp ./example-vars.json ./config.json
    status:
      - test -f config.json

  build:
    cmds:
      - packer build {{.packer_args}} {{.config_path}}

  validate:
    cmds:
      - packer validate {{.packer_args}} {{.config_path}}

  cleanup-isos:
    cmds:
      - rm -rf ./isos

  ubuntu-18-iso:
    cmds:
      - mkdir -p ./isos
      - curl -C - -o ./isos/{{.ubuntu_18_04_iso_name}} {{.ubuntu_18_04_iso_url}}