Instance sample includes ssh_key_thumbnail

instance.tf.json

{
  "variable": {
    "base_image": {
      "default": "Ubuntu Server 14.04 LTS"
    },
    "ssh_username": {
      "default": "terraform"
    },
    "instance_type": {
      "default": "Basic_A2"
    }
  },
  "resource": {
    "azure_instance": {
      "gamma": {
        "depends_on": ["null_resource.ssh_key"],
        "name": "test-gamma",
        "image": "${var.base_image}",
        "size": "${var.instance_type}",
        "location": "${module.azure.region}",
        "username": "${var.ssh_username}",
        "ssh_key_thumbprint": "${file(\"./ssl/ssh_thumbprint\")}",
        "storage_service_name": "${azure_storage_service.test.name}",
        "hosted_service_name": "${azure_hosted_service.terraform.name}",
        "subnet": "subnet_gamma",
        "virtual_network": "${azure_virtual_network.default.name}",
        "endpoint": {
          "name": "SSH",
          "protocol": "tcp",
          "public_port": 22,
          "private_port": 22
        }
      }
    }
  }
}