DataBricks Sample Terraform Code causes error in AWS VPC module-CodePudding

I'm completely new to DataBricks and trying to deploy an E2 workspace using the sample Terraform code provided by DataBricks. I've just started with the VPC part:

data "aws_availability_zones" "available" {}

module "vpc" {
  source  = "terraform-aws-modules/vpc/aws"
  # version = "3.2.0"

  name = local.prefix
  cidr = var.cidr_block
  azs  = data.aws_availability_zones.available.names

  enable_dns_hostnames = true
  enable_nat_gateway   = true
  single_nat_gateway   = true
  create_igw           = true

  private_subnets = [cidrsubnet(var.cidr_block, 3, 1),
                     cidrsubnet(var.cidr_block, 3, 2)]

  manage_default_security_group = true
  default_security_group_name = "${local.prefix}-sg"

  default_security_group_egress = [{
    cidr_blocks = "0.0.0.0/0"
  }]

  default_security_group_ingress = [{
    description = "Allow all internal TCP and UDP"
    self        = true
  }]
}

When I run terraform plan I get this error:

│ Error: Error in function call
│
│   on .terraform/modules/vpc/main.tf line 1090, in resource "aws_nat_gateway" "this":
│ 1090:   subnet_id = element(
│ 1091:     aws_subnet.public.*.id,
│ 1092:     var.single_nat_gateway ? 0 : count.index,
│ 1093:   )
│     ├────────────────
│     │ aws_subnet.public is empty tuple
│     │ count.index is 0
│     │ var.single_nat_gateway is true
│
│ Call to function "element" failed: cannot use element function with an empty list.

Would really appreciate any pointers on what is going wrong here.

CodePudding user response：

You set that you want internet gateway create_igw = true, but you haven't specified public_subnets. You must have public_subnets if you have igw.