- `bucket_name` (string) - The name of the bucket your image is in. - `channel` (string) - The name of the channel to use when retrieving your image. Either this or `iteration_id` MUST be set. Mutually exclusive with `iteration_id`. If using several images from a single iteration, you may prefer sourcing an iteration first, and referencing it for subsequent uses, as every `hcp_packer_image` with the channel set will generate a potentially billable HCP Packer request, but if several `hcp_packer_image`s use a shared `hcp_packer_iteration` that will only generate one potentially billable request. - `iteration_id` (string) - The ID of the iteration to use when retrieving your image Either this or `channel` MUST be set. Mutually exclusive with `channel` - `cloud_provider` (string) - The name of the cloud provider that your image is for. For example, "aws" or "gce". - `region` (string) - The name of the cloud region your image is in. For example "us-east-1".