Terraform, instantiate the same module multiple times

main.tf

provider "aws" {
  region = "ap-southeast-2"
}

resource "aws_s3_bucket" "my_bucket" {
  bucket = "test-bucket-whatever-1jfibabl"
}

module "file_a" {
  source = "./mod-a"

  bucket_name = aws_s3_bucket.my_bucket.id
  file_path = "../foo.txt"
}

module "file_b" {
  source = "./mod-a"

  bucket_name = aws_s3_bucket.my_bucket.id
  file_path = "../bar.txt"
}

Makefile

export AWS_PROFILE := your-aws-profile

auto_approve_target = apply destroy

init apply destroy:
	cd infra && terraform $@ $(if $(filter $@,$(auto_approve_target)),-auto-approve)

mod-a_main.tf

# This file should be named as mod-a/main.tf

variable "file_path" {}
variable "bucket_name" {}

locals {
  path_in_bucket = "foo/${basename(var.file_path)}"
}

resource "aws_s3_bucket_object" "object" {
  bucket = var.bucket_name
  key    = local.path_in_bucket
  source = var.file_path
}

output "path_in_bucket" {
  value = local.path_in_bucket
}