Terraform attach disks dynamic - terraform

Question

Point: I need to dynamically attach disks created with a for_each loop to VM
resource "yandex_compute_disk" "volume" {
for_each = var.volumes
name = each.value["name"]
size = each.value["size"]
type = each.value["type"]
resource "yandex_compute_instance" "vps" {
count = var.server_count
name = var.server_count > 1 ? "${var.server_name}${count.index}" : var.server_name
platform_id = var.platform_id
zone = var.zone
....
....
....
dynamic "secondary_disk" {
for_each = var.volumes
content {
disk_id = yandex_compute_disk.volume.id -- here is problem
auto_delete = var.server_volume_auto_delete
}
}
error:
│
│ For example, to correlate with indices of a referring resource, use:
│ yandex_compute_disk.volume[each.key]```
But its not work like that yandex_compute_disk.volume[each.key].id

Answer 1

If the requested attribute is being exported, then this might work:
resource "yandex_compute_instance" "vps" {
count = var.server_count
name = var.server_count > 1 ? "${var.server_name}${count.index}" : var.server_name
platform_id = var.platform_id
zone = var.zone
....
....
....
dynamic "secondary_disk" {
for_each = var.volumes
content {
disk_id = yandex_compute_disk.volume[secondary_disk.name].id
auto_delete = var.server_volume_auto_delete
}
}
The important thing to note about using dynamic blocks is the iterator [1] name. If you do not set it, it will default to the label of the dynamic block, i.e., secondary_disk in this case. At a very high level, you could say that iterator name replaces the each object.
[1] https://developer.hashicorp.com/terraform/language/expressions/dynamic-blocks