ansible inventory files from terraform

gistfile1.txt

### variables

variable "env" {}
variable "riak_count" {}
variable "elastic_count" {}

### hostname.tpl
${name}-${env}-${format("%02s",index)} ${extra}

### ansible.tpl
[riak]
${riak_hosts}
[elastic]
${elastic_hosts}

[${env}:children]
riak
elastic


#### outputs.tf
data "null_data_source" "inventory" {
  inputs = {
    riak = "${join(",",vsphere_virtual_machine.riak.*.network_interface.0.ipv4_address)}",
    elastic = "${join(",", vsphere_virtual_machine.elastic.*.network_interface.0.ipv4_address)}"
    }
}


data "template_file" "riak_ansible" {
  count = "${var.riak_count}"
  template = "${file("${path.module}/hostname.tpl")}"
  vars {
    index = "${count.index + 1}"
    name  = "riak"
    env   = "${var.env}"
    extra = " ansible_host=${element(split(",",data.null_data_source.inventory.inputs.riak),count.index)}"
    # extra = ""
  }
}
data "template_file" "elastic_ansible" {
  count = "${var.elastic_count}"
  template = "${file("${path.module}/hostname.tpl")}"
  vars {
    index = "${count.index + 1}"
    name  = "elastic"
    env   = "${var.env}"
    extra = " ansible_host=${element(split(",",data.null_data_source.inventory.inputs.elastic),count.index)}"
    # extra = ""
  }
}

data "template_file" "ansible_hosts" {
  template = "${file("${path.module}/ansible.tpl")}"
  vars {
    env         = "${var.env}"
    riak_hosts   = "${join("\n",data.template_file.riak_ansible.*.rendered)}"
    elastic_hosts   = "${join("\n",data.template_file.elastic_ansible.*.rendered)}"
  }
}

output "ansible_hosts" {
	value = "${data.template_file.ansible_hosts.rendered}"
}