Terraform : for_each one by one

Question

I have created a module on terraform, this module creates aws_servicecatalog_provisioned_product resources.
When I call this module from the root I am using for_each to run into a list of objects.
The module runs into this list of objects and creates the aws_servicecatalog_provisioned_product resources in parallel.
Is there a way to create the resources one by one? I want that the module will wait for the first iteration to be done and to create the next just after.

Answer 1

I am using terraform templatefile that creates resources with a depends on order, and then terraform creates resources one by one.

Here is the code:

locals {

     expanded_accounts = [ 
      {
          AccountEmail                           = [email protected]
          AccountName                         = example1
          ManagedOrganizationalUnit           = example_ou1
          SSOUserEmail                        = [email protected]
          SSOUserFirstName                    = Daniel
          SSOUserLastName                     = Wor
          ou_id                               = ou_id1
      },
      {
          AccountEmail                           = [email protected]
          AccountName                         = example2
          ManagedOrganizationalUnit           = example_ou2
          SSOUserEmail                        = [email protected]
          SSOUserFirstName                    = Ben
          SSOUserLastName                     = John
          ou_id                               = ou_id2
     }
     ]

  previous_resource = [
    for acc in local.expanded_accounts :
    acc.AccountName
  ]

     resources = { res = local.expanded_accounts, previous = concat([""], local.previous_resource)
}

resource "local_file" "this" {
  content              = templatefile("./provisioned_accounts.tpl", local.resources)
  filename             = "./generated_provisioned_accounts.tf"
  directory_permission = "0777"
  file_permission      = "0777"

  lifecycle {
    ignore_changes = [directory_permission, file_permission, filename]
  }
}

provisioned_accounts.tpl configuration:

%{ for acc in res }
resource "aws_servicecatalog_provisioned_product" "${acc.AccountName}" {
  name                     = "${acc.AccountName}"
  product_id               = replace(data.local_file.product_name.content, "\n", "")
  provisioning_artifact_id = replace(data.local_file.pa_name.content, "\n", "")
  

  provisioning_parameters {
    key   = "SSOUserEmail"
    value = "${acc.SSOUserEmail}"
  }
  provisioning_parameters {
    key   = "AccountEmail"
    value = "${acc.AccountEmail}"
  }
  provisioning_parameters {
    key   = "AccountName"
    value = "${acc.AccountName}"
  }
  provisioning_parameters {
    key   = "ManagedOrganizationalUnit"
    value = "${acc.ManagedOrganizationalUnit} (${acc.ou_id})"
  }
  provisioning_parameters {
    key   = "SSOUserLastName"
    value = "${acc.SSOUserLastName}"
  }
  provisioning_parameters {
    key   = "SSOUserFirstName"
    value = "${acc.SSOUserFirstName}"
  }

  timeouts {
    create = "60m"
  }

%{if index != 0 }
  depends_on = [aws_servicecatalog_provisioned_product.${previous[index]}]
%{ endif }

}

%{~ endfor ~}

Answer 2

Is there a way to create the resources one by one?

Sadly, there is not such way, unless you remove for_each and create all the modules separately with depends_on.

TF is not a procedural language, and it always will do things in parallel for for_each and count.