Resource does not have attribute for variable - Terraform remote state

Question

Having an issue getting Terraform remote state working in one of my projects. The statefile is remote in S3. I am importing like so:

data "terraform_remote_state" "management" {
  backend = "s3"

  config {
    bucket = "testbucket"
    key    = "subfolder/terraform.tfstate"
    region = "us-west-2"
  }
}

I can see the output at the root level of the above statefile:

            "outputs": {
            "cidr": {
                "sensitive": false,
                "type": "string",
                "value": "10.90.0.0/16"
            },

I am using the remote state like so:

module "dev-alpha-application" {
  source          = "../../modules/application"
  envname         = "test-app"
  baseami         = "ami-a042f4d8"
  key_name        = "pb-smarsh-test"
  clui_baseami    = "ami-xxxxxxxx"
  adui_baseami    = "ami-xxxxxxxx"
  cidr            = "10.80.0.0/16"
  management_cidr = "${data.terraform_remote_state.management.cidr}"

  vpn_gateway_id = "cgw-xxxxxxxx"

  cidrs = "${list("${data.terraform_remote_state.management.cidr}", "${module.dev-alpha-application.cidr}")}"

Unless I have overlooked something stupid, this should work, however when I run a terraform apply, I get the following error:

* module.dev-alpha-application.var.management_cidr: Resource 'data.terraform_remote_state.management' does not have attribute 'cidr' for variable 'data.terraform_remote_state.management.cidr'

Terraform init works as expected. Any assistance would be greatly appreciated. I have tried to include as much info as possible .

Edit - In Debug mode, it appears it is opening the remote state file ok

-----------------------------------------------------
2018/04/10 09:05:10 [DEBUG] [aws-sdk-go] <?xml version="1.0" encoding="UTF-8"?>
<ListBucketResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/"><Name>testbucket</Name><Prefix>env:/</Prefix><Marker></Marker><MaxKeys>1000</MaxKeys><IsTruncated>false</IsTruncated></ListBucketResult>
2018/04/10 09:05:10 [DEBUG] [aws-sdk-go] DEBUG: Request s3/GetObject Details:
---[ REQUEST POST-SIGN ]-----------------------------
GET /subfolder/terraform.tfstate HTTP/1.1
Host: testbucket.s3.us-west-2.amazonaws.com
User-Agent: aws-sdk-go/1.12.59 (go1.9.1; linux; amd64) APN/1.0 HashiCorp/1.0 Terraform/0.11.3
Authorization: AWS4-HMAC-SHA256 Credential=AKIAI6X7Y3APAUTZZQOQ/20180410/us-west-2/s3/aws4_request, SignedHeaders=host;x-amz-content-sha256;x-amz-date, Signature=716689e2124dd2a689b528c0cb51b07aeaf791cf577fa1a4fd17a79fb401b957
X-Amz-Content-Sha256: e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
X-Amz-Date: 20180410T080510Z
Accept-Encoding: gzip


-----------------------------------------------------
2018/04/10 09:05:11 [DEBUG] [aws-sdk-go] DEBUG: Response s3/GetObject Details:
---[ RESPONSE ]--------------------------------------
HTTP/1.1 200 OK
Connection: close
Content-Length: 386104
Accept-Ranges: bytes
Content-Type: application/json
Date: Tue, 10 Apr 2018 08:05:12 GMT
Etag: "1df4aaad48451707a79306a8f6a1c51c"
Last-Modified: Mon, 09 Apr 2018 14:53:03 GMT
Server: AmazonS3
X-Amz-Id-2: 92XqUEj319Uq5KhYFWvrLQ3O7VooOMMQ4GxY0keRKYY72Q5mpOgjeZ78w20AzjCSFLuZZycfEqU=
X-Amz-Request-Id: 448DB8C5E4B70A9A
X-Amz-Server-Side-Encryption: AES256
X-Amz-Version-Id: GjI6glV8oa9_.eOFSc5GFGVtTJBnrEmL

But I also see this in the debug logs:

2018/04/10 09:02:17 [DEBUG] Resource state not found for "data.terraform_remote_state.management": data.terraform_remote_state.management

Answer 1

For those who has similar problem. It is mostly because the documentation of terraform is not up-to-date. For terraform <=0.11 you need to access the output variables directly without 'outputs' e.g. data.terraform_remote_state.management.cidr.

With >=0.12 it will be with 'outputs' e.g. data.terraform_remote_state.management.outputs.cidr.

Documentation on the website will also be fixed but it is currently not deployed.

https://github.com/hashicorp/terraform/commit/142ecfefe063c8f78cdbcbaaa3b5bb963831a98e#diff-4b355b6363c6f1e57a6132decd8502e9