Terraform - Reference for_each from a module output - terraform

Question

I am trying to use Terraform to create multiple storage containers, and then upload multiple blobs to each container.
I have the part of creating multiple containers working, but can't figure out how to reference the for_each output of each container when uploading the blobs.
Storage Container Module (Works)
resource "azurerm_storage_container" "azure" {
for_each = toset(var.storage_containers)
name = each.value
storage_account_name = var.storage_account_name
container_access_type = var.storage_account_container_access_type
}
output "azurerm_storage_container_name" {
value = toset(keys(azurerm_storage_container.azure))
}
Child Module (Works)
module "storage_container" {
source = "C:/TerraformModules/modules/azurerm/azurerm_storage_container"
storage_account_name = module.storage_account.azurerm_storage_account_name
storage_containers = var.STORAGE_CONTAINER_NAMES
tags = var.TAGS
}
Code to upload blob (doesn't work for trying to upload into each container)
**In a variables.tf file**
variable "STORAGE_CONTAINER_DEFAULT_BLOBS" {
description = "The default blobs in each storage container"
type = list(string)
}
**In a vars.auto.tfvars file**
STORAGE_CONTAINER_DEFAULT_BLOBS = ["one", "two", "three"]
**In a main.tf file**
resource "azurerm_storage_blob" "storage_blob" {
for_each = toset(var.STORAGE_CONTAINER_DEFAULT_BLOBS)
name = each.value
storage_account_name = module.storage_account.azurerm_storage_account_name
storage_container_name = module.storage_container[each.value].azurerm_storage_container_name
type = "Block"
source_content = "blob file"
}
If I were to set the container name in storage_container_name, it works and the container gets each blob. But I'm not able to reference the container from the module.
I have this error:
Error: Invalid index
on storage_blobs.tf line 5, in resource "azurerm_storage_blob" "storage_blob":
5: storage_container_name = module.storage_container[each.value].azurerm_storage_container_name
|----------------
| each.value is "two"
| module.storage_container is object with 1 attribute "azurerm_storage_container_name"
The given key does not identify an element in this collection value.
What I need to achieve:
resource "azurerm_storage_blob" "storage_blob" {
for_each = toset(var.STORAGE_CONTAINER_DEFAULT_BLOBS)
name = each.value
storage_account_name = module.storage_account.azurerm_storage_account_name
storage_container_name = # How to reference the storage accounts created with the `storage_container ` module? #
type = "Block"
source_content = "blob file"
}

Answer 1

storage_container_name takes only one value, not a list of values. So if you have 3 STORAGE_CONTAINER_DEFAULT_BLOBS and n number of var.storage_containers you have to iterate n*3 times in azurerm_storage_blob.
Thus, you can try the following with setproduct:
resource "azurerm_storage_blob" "storage_blob" {
for_each = {for idx, val in setproduct(module.storage_container.azurerm_storage_container_name, var.STORAGE_CONTAINER_DEFAULT_BLOBS): idx=>val}
name = each.value[1]
storage_account_name = module.storage_account.azurerm_storage_account_name
storage_container_name = each.value[0]
type = "Block"
source_content = "blob file"
}