{ "variables": { "bucket_name": null, "account_file": null, "project_id": null }, "builders": [{ "type": "googlecompute", "bucket_name": "{{user `bucket_name`}}", "account_file": "{{user `account_file`}}", "project_id": "{{user `project_id`}}", "image_name": "packerbats-minimal-{{timestamp}}", "source_image": "debian-7-wheezy-v20141108", "zone": "us-central1-a" }] }