Terraform modules depends_on workaround

terraform.tf

# File fancy-app-module/variables.tf

variable depends_on { default = [], type = "list"}


# File my-app.tf

module "app" {
    source  = "modules/fancy-app-module"

    # Wait for resources and associations to be created
    depends_on = [
        "${aws_alb_target_group.app.arn}"
    ]
}

resource "aws_alb_target_group" "app" {
    name     = "app-group"
}

resource "aws_alb_listener" "front_end" {
   # Association of default_action takes some time and
   # if this action is required by you module, it's creation
   # might fail due to async provisioning of the
   # resources by terraform
   default_action {
        target_group_arn = "${aws_alb_target_group.app.id}"
        type             = "forward"
    }
}