Terraform aws - not able to output vpc main_route_table_id

[worldspawn]

Hi,

i'm trying to output a newly created vpc's main_route_table_id attribute.

output "main_route_table_id" {
  value "${aws_vpc.main.main_route_table_id}"
}

However it always comes out as blank.

As you can see I don't have trouble outputting other values.

I can see it's being set in the tfstate file.

"aws_vpc.main": {
                    "type": "aws_vpc",
                    "primary": {
                        "id": "vpc-7471e011",
                        "attributes": {
                            "cidr_block": "10.0.0.0/16",
                            "default_network_acl_id": "acl-510f6634",
                            "default_security_group_id": "sg-0d360968",
                            "dhcp_options_id": "dopt-18f6177d",
                            "enable_dns_hostnames": "true",
                            "enable_dns_support": "true",
                            "id": "vpc-7471e011",
                            "instance_tenancy": "default",
                            "main_route_table_id": "rtb-26fe9443",
                            "tags.#": "2",
                            "tags.Application": "test2",
                            "tags.Production": "0"
                        }
                    }
                }

Not sure what I'm doing wrong :'(

(Terraform v0.6.8)

[jen20]

Hi @worldspawn. Thanks for reporting this - your configuration looks correct as far as I can see, so this looks like a bug. Could you post the resource definitions for your VPC and routing table as well, and I'll try to reproduce/fix?

[worldspawn]

Here it is:

variable "aws_access_key" {}
variable "aws_secret_key" {}
variable "application_name" {}
variable "region" {
  default = "ap-southeast-2"
}
variable "production" {
  default = "false"
}

provider "aws" {
    access_key = "${var.aws_access_key}"
    secret_key = "${var.aws_secret_key}"
    region = "${var.region}"
}

resource "aws_vpc" "main" {
    cidr_block = "10.0.0.0/16"
    instance_tenancy = "default"
    enable_dns_support = true
    enable_dns_hostnames = true

    tags {
        Application = "${var.application_name}"
        Production = "${var.production}"
    }
}

resource "aws_subnet" "main" {
    vpc_id = "${aws_vpc.main.id}"
    cidr_block = "10.0.0.0/24"
    availability_zone = "${var.region}a"

    tags {
        Application = "${var.application_name}"
        Production = "${var.production}"
    }
}

resource "aws_subnet" "alt" {
    vpc_id = "${aws_vpc.main.id}"
    cidr_block = "10.0.1.0/24"
    availability_zone = "${var.region}b"

    tags {
        Application = "${var.application_name}"
        Production = "${var.production}"
    }
}

resource "aws_internet_gateway" "gw" {
    vpc_id = "${aws_vpc.main.id}"

    tags {
      Application = "${var.application_name}"
      Production = "${var.production}"
    }
}

output "vpc_id" {
  value = "${aws_vpc.main.id}"
}

output "main_subnet_id" {
  value = "${aws_subnet.main.id}"
}

output "alt_subnet_id" {
  value = "${aws_subnet.alt.id}"
}

output "main_route_table_id" {
  value "${aws_vpc.main.main_route_table_id}"
}

Note i'm not defining a route table, i'm expecting it to give me the name of the default route table created when i create the vpc.

[phinze]

Hi @worldspawn - just dug into this and verified the code is correct. That's when I noticed the cause - your main_route_table_id output is missing an equals sign. Easy fix! 😀

I'll look into whether we can provide a better error message for this, but in the meantime that should get you the proper behavior.

[worldspawn]

Sorry about that :) thanks

[ghost]

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