Getting Started with Terraform - Second Edition

Configuring modules

Let's list the data we need to pass to the module:

• Name of the application
• VPC ID
• Subnet ID

That should be sufficient for now. Update the module inside template.tf to look as follows:

module "mighty_trousers" { 
  source = "./modules/application" 
  vpc_id = "${aws_vpc.my_vpc.id}" 
  subnet_id = "${aws_subnet.public.id}" 
  name = "MightyTrousers" 
} 

Passing data like this is not enough though. We need to define variables inside the module template. The thing is, our tempate.tf is a module itself, a special module named root module. That's what you saw on the last graph we drew--resources were coming from the root module. So, we were actually already using modules all this time, and every module, including the root module, can ...