Change Infrastructure

Now that we have bucket created, let’s modify it. Here’s the demo/main.tf again.

app/stacks/demo/main.tf

resource "random_pet" "this" {
  length = 2
}

module "bucket" {
  source     = "../../modules/example"
  bucket     = "bucket-${random_pet.this.id}"
  acl        = var.acl
}

As you can see there’s a var.acl variable. One way to update the infrastructure is to change the variable in the variables.tf file directly.

app/stacks/demo/variables.tf

variable "bucket" {
  description = "The name of the bucket. If omitted, Terraform will assign a random, unique name." # IE: terraform-2020052606510241590000000
  type        = string
  default     = null
}

variable "acl" {
  description = "The canned ACL to apply. Defaults to 'private'."
  type        = string
  default     = "private"
}

However, you can also use tfvars files. Terraspace will automatically use app/stacks/demo/tfvars files according the TS_ENV value. The default value is TS_ENV=dev. We’ll use tfvars files so we can use the same code for different environments.

Generate Starter Tfvars Files

Addtionally, Terraspace can generate starter tfvar files for us with the terraspace seed command.

$ terraspace seed demo
Reading: .terraspace-cache/us-west-2/dev/stacks/demo/variables.tf
      create  app/stacks/demo/tfvars/dev.tfvars
$

The produced file looks something like this:

app/stacks/demo/tfvars/dev.tfvars

# Optional variables:
# bucket = null
# acl  = "private" # <= change this line

Terraspace parses the demo/variables.tf file to generate the tfvars/dev.tfvars file. It detected that all the variables are optional. We’ll uncomment acl and change it to acl = "public-read".

app/stacks/demo/tfvars/dev.tfvars

# Optional variables:
# bucket = null
acl = "public-read" # <= was changed

Next, we’ll update the infrastructure.

More tools: