Handle optional dynamic blocks for DynamoDB GSI

  dynamic "global_secondary_index" {
    for_each = var.global_secondary_index_map
    content {
      hash_key           = global_secondary_index.value.hash_key
      name               = global_secondary_index.value.name
      non_key_attributes = lookup(global_secondary_index.value, "non_key_attributes", null)
      projection_type    = global_secondary_index.value.projection_type
      range_key          = lookup(global_secondary_index.value, "range_key", null)
      read_capacity      = lookup(global_secondary_index.value, "read_capacity", null)
      write_capacity     = lookup(global_secondary_index.value, "write_capacity", null)
    }
  }

variable "global_secondary_index_map" {
  type = list(object({
    hash_key           = string
    name               = string
    non_key_attributes = list(string)
    projection_type    = string
    range_key          = string
    read_capacity      = number
    write_capacity     = number
  }))
  default = []

I am trying to use range_key, non_key_attributes as an optional unfortunately doesn’t working with null.