creating a list of list objects terraform - terraform

Question

I'm setting up a terraform repo for my snowflake instance and bringing in a list of users to start managing.
I have a module called users
and have the following files:
I have a variable defined as follows.
variable "users" {
type = list(object(
{
name = string
comment = string
default_role = string
disabled = bool
must_change_password = bool
display_name = string
email = string
first_name = string
last_name = string
default_warehouse = string
}
)
)
}
now inside users.tf I want to hold a list of all my users based on the above variable, I thought I could define it as follows:
users {
user_1 = {
name = 'x'
},
user_2 = {
name = 'y'
}
}
however, when I run Terraform validate on this it gives me the error that a user block is not expected here.
Can someone tell me my error and give me some guidance if I'm doing this correctly?
My intention is to have a file to hold all my users that I then define with a dynamic block inside my main.tf file within this module.
I can then reference the dynamic block inside the outputs.tf which will give me access to the users inside said module in the global project namespace.

Answer 1

Looks to me like you are attempting to configuring your users as an object:
users {
user_1 = {
name = "x"
},
user_2 = {
name = "y"
}
}
but you actually set your variable constraint to a list of objects. So it should be:
users = [
{
name = "user_1"
# other fields
},
{
name = "user_2"
# other fields
}
]
Here is a full working example:
modules/users/variables.tf
variable "users" {
type = list(object({
name = string
}))
}
modules/users/outputs.tf
output "users" {
value = var.users
}
main.tf
module "users" {
source = "./modules/users"
users = [
{ name = "user_1" },
{ name = "user_2" }
]
}
output "users" {
value = module.users.users
}
plan output
Changes to Outputs:
+ users = [
+ {
+ name = "user_1"
},
+ {
+ name = "user_2"
},
]

Answer 2

Your config syntax and usage is completely correct here. Your config file organization is the issue here. users.tf is a Terraform variables file, and therefore should have the .tfvars extension. If you rename the file from users.tf to e.g. users.tfvars, then you can specify it as an input with the -var-file=users.tfvars argument with the CLI or otherwise as per standard usage. You can see more information in the documentation.
On a side note: it is not really best practices to manage an entire module just for managing a set of users for a specific service. If you follow this design pattern in the future, then your codebase will not scale very well, and could easily become unmanageably large.