How to for_each through a list(objects) in Terraform 0.12

Question

I need to deploy a list of GCP compute instances. How do I loop for_each through the "vms" in a list of objects like this:

    "gcp_zone": "us-central1-a",     "image_name": "centos-cloud/centos-7",     "vms": [       {         "hostname": "test1-srfe",         "cpu": 1,         "ram": 4,         "hdd": 15,         "log_drive": 300,         "template": "Template-New",         "service_types": [           "sql",           "db01",           "db02"         ]       },       {         "hostname": "test1-second",         "cpu": 1,         "ram": 4,         "hdd": 15,         "template": "APPs-Template",         "service_types": [           "configs"         ]       }     ]     } 

Answer 1

Seem's like I found what to do. If you pass not the maps of maps but the list of maps you can use such code

resource "google_compute_instance" "node" {     for_each = {for vm in var.vms:  vm.hostname => vm}      name         = "${each.value.hostname}"     machine_type = "custom-${each.value.cpu}-${each.value.ram*1024}"     zone         = "${var.gcp_zone}"      boot_disk {         initialize_params {         image = "${var.image_name}"         size = "${each.value.hdd}"         }     }      network_interface {         network = "${var.network}"     }      metadata = {         env_id = "${var.env_id}"         service_types = "${join(",",each.value.service_types)}"   } } 

It will create actual number of instance and when you remove for example middle one of three(if you create three:)), terraform will remove what we asked.