how to same variable with different values in different env in terraform module - variables

Question

I am using the terraform s3 module https://github.com/terraform-aws-modules/terraform-aws-s3-bucket. I created a wrapper module around this module for creating a s3 bucket. Currently there are 3 different aws account where in this s3 modules changes should be used for creating the buckets. Since there are 3 different accounts, the grant and the owner values are different for each of the account. Currently, I have hardcoded these value for the buckets that I create
s3_bucket.tf
module "sample_bucket" {
source = "../../../../modules/aws/data/s3_bucket"
bucket = "sample_bucket"
lifecycle_rule = [
rule here
]
}
>../../../../modules/aws/data/s3_bucket/main.tf file
module "s3_bucket" {
source = "terraform-aws-modules/s3-bucket/aws"
version = "3.6.0"
bucket = var.bucket
attach_public_policy = var.attach_public_policy
server_side_encryption_configuration = var.server_side_encryption_configuration
grant = var.grant
owner = var.owner
cors_rule = var.cors_rule
lifecycle_rule = var.lifecycle_rule
tags = var.tags
versioning = var.versioning
replication_configuration = var.replication_configuration
force_destroy = var.force_destroy
}
> ../../../../modules/aws/data/s3_bucket/variable.tf file
variable "grant" {
description = "An ACL policy grant. Conflicts with `acl`"
type = any
default = []
}
variable "owner" {
description = "Bucket owner's display name and ID. Conflicts with `acl`"
type = map(string)
default = {}
}
I want to use the grant and the owner variable from the module file in the main.tf file and not hard code these values for each of the accounts in s3_bucket.tf for the buckets I create. Can someone help me here on how to use the same variable grant and onwer with different values for each of the account

Answer 1

You can use Terraform Workspaces for different environments. An example of how you could use workspaces:
module "sample_bucket" {
source = "../../../../modules/aws/data/s3_bucket"
bucket = "sample_bucket"
grant = "${var.grant}-${terraform.workspace}"
owner = "${var.owner}-${terraform.workspace}"
lifecycle_rule = [
rule here
]
}
P.S You might have to handle grant and owner differently from the above code since they are list and map
Update:
In case of different folder for each environment, you can define a separate variables.tfvars and pass it in as per the need. Read more about Input Variables here
Within each folder, you can run and terraform apply/plan and it will automatically detect your terraform.tfvars file.
s3_bucket
│ main.tf
└───dev
│ │ terraform.tfvars
│ │
└───stg
│ │ terraform.tfvars
│ │
└───prod
│ │ terraform.tfvars
│ │