Hi - I have created a module I want to use across multiple providers (just two AWS providers for 2 regions). How can I set a resource’s provider value via variable from a calling module? I am calling a module codebuild.tf (which I want to be region agnostic) from a MGMT module named cicd.tf - Folder structure:
- main.tf
- /MGMT/
→ cicd.tf - /modules/codebuild/
→ codebuild.tf
main.tf:
terraform {
required_version = ">= 1.0.10"
backend "s3" {
}
required_providers {
aws = {
source = "hashicorp/aws"
version = "~> 3.0"
}
}
}
# default AWS provider for MGMT resources in us-east-1 and global
provider "aws" {
region = "us-east-1"
}
# DEV Account resources in us-east-1 and global
provider "aws" {
region = "us-east-1"
assume_role {
role_arn = "arn:aws:iam::accountid:role/dev-rolename"
}
alias = "dev_us-east-1"
}
# DEV Account resources in us-west-2 and global
provider "aws" {
region = "us-west-2"
assume_role {
role_arn = "arn:aws:iam::accountid:role/dev-rolename"
}
alias = "dev_us-west-2"
}
module "MGMT" {
source = "./MGMT"
count = var.aws_env == "MGMT" ? 1 : 0
aws_env = var.aws_env
}
When I build my TF, its under the MGMT AWS account which uses the the default aws provider that doesn’t have an alias - I am then trying to set a provider with an AWS IAM Role (that’s cross account) when I am calling the module (I made the resource a module because I want to run it in multiple regions):
/MGMT/cicd.tf:
# DEV in cicd.tf
# create the codebuild resource in the assumed role's us-east-1 region
module "dev_cicd_iac_us_east_1" {
source = "../modules/codebuild/"
input_aws_provider = "aws.dev_us-east-1"
input_aws_env = var.dev_aws_env
}
# create the codebuild resource in the assumed role's us-west-2 region
module "dev_cicd_iac_us_west_2" {
source = "../modules/codebuild/"
input_aws_provider = "aws.dev_us-west_2"
input_aws_env = var.dev_aws_env
}
/modules/codebuild/codebuild.tf:
# Code Build resource here
variable "input_aws_provider" {}
variable "input_aws_env" {}
resource "aws_codebuild_project" "codebuild-iac" {
provider = tostring(var.input_aws_provider) # trying to make it a string, with just the var there it looks for a var provider
name = "${var.input_aws_env}-CodeBuild-IaC"
# etc...
}
I get the following error when I plan the above:
│ Error: Invalid provider reference
│ On modules/codebuild/codebuild.tf line 25: Provider argument requires
│ a provider name followed by an optional alias, like "aws.foo".