Terraform Modules

• Modules are reusable terraform templates
• modules will not have providers and can be called by multiple templates
  
• Modules can be present in (module sources)
  • local folder
  • git
  • Terraform Cloud
• To call a module we use a module block

module <name> {
    source = "<module-source>"
    arg1 = value1
    arg2 = value2
    ...
    argn = valuen
}

• To create a module, just create a new folder with some name, ensure you have
  • resources
  • variables (inputs/arguments)
  • outputs (outputs/attributes)
• Added module for security group locally
• Refer Here for modules for vpc, security group
• Terraform also has a registry where lots of modules are already available
• Refer Here for a community module on vpc and try creating vpc with this module

module "vpc" {
  source = "terraform-aws-modules/vpc/aws"
  version = "5.21.0"

  name = "my-vpc"
  cidr = "10.0.0.0/16"

  azs             = ["ap-south-1a", "ap-south-1b"]
  private_subnets = ["10.0.1.0/24", "10.0.2.0/24"]
  public_subnets  = ["10.0.101.0/24", "10.0.102.0/24"]

  enable_nat_gateway = false
  enable_vpn_gateway = false

  tags = {
    Terraform = "true"
    Environment = "dev"
  }
}