Need to extract the subnet id from the data source based on the region

Question

I have data source module where I am extracting the subnet id by passing subnet name.

File is in the data module:

Module/data/data.tf

data "aws_vpc" "vpc-id" {
  provider = "${var.region}"
  filter {
    name   = "tag:Name"
    values = ["kdt-vpc"]
  }

}

data "aws_subnet" "subnetid" {
  provider = "${var.region}"
  filter {
    name   = "vpc-id"
    values = [data.aws_vpc.vpc-id.id]
  }

  filter {
    name   = "tag:Name"
    values = ["kdt-private-subnet-0"]
  }
}

Variables.tf

variable "region" {
  description = "vpc name"
  type        = string
  default     = "aws.west"
}

main.tf where Iam calling the data module.

module "data" {
    source  =   "./data"
    region = "aws.west"
}


output "subnet_id" {
    value = module.data.subnetid
}

Provider.tf

terraform {
    required_providers {
        aws = {
            source = "hashicorp/aws"
            #version = "~> 3.0"
            #configuration_aliases = [ aws.alternate ]
        }
    }
}

provider "aws" {
  region = "us-east-1" 

}

provider "aws" {
  alias  = "west"
  region = "us-east-2"

}

While running the terraform apply i am getting the below errors

Error: Invalid provider configuration reference │ │ on data\data.tf line 2, in data "aws_vpc" "vpc-id": │ 2: provider = "${var.region}" │ │ The provider argument requires a provider type name, optionally followed by a period and then a │ configuration alias. ╵ ╷ │ Error: Invalid provider configuration reference │ │ on data\data.tf line 11, in data "aws_subnet" "subnetid": │ 11: provider = "${var.region}" │ │ The provider argument requires a provider type name, optionally followed by a period and then a
│ configuration alias. ╵

Error: Unsupported attribute │ │ on main.tf line 18, in output "subnet_id": │ 18: value = module.data.subnetid │ ├──────────────── │ │ module.data is a object │ │ This object does not have an attribute named "subnetid".

Answer 1

Instead of passing a region name to the module, and then trying to use a specific provider based on that, you need to actually pass the provider itself into the module (documented here):

module "data" {
    source  =   "./data"
    providers = {
      aws = aws.west
    }
}

Then just completely remove the provider = "${var.region}" lines inside the data module code.