Amazon web services 传递ec2实例ID时terraform中的属性值类型错误

我正在使用下面的代码创建3个ec2实例并向负载平衡器注册它们

变量 ec2创建 向负载平衡器注册 但是当我传递ec2实例ID时，如下所示

module "alb_engine-ui" {
  source = "./modules/load-balancer"
  env = "${lower(var.env)}"
  project = "engine-ui"
  vpc_id = "${data.aws_vpc.main.id}"
  public_subnet1_id = "${var.public_subnet1_id}"
  public_subnet2_id = "${var.public_subnet2_id}"
  health_check_target_group_path = "/"
  certificate_arn = "${var.certificate_arn}"
  alb_target_group_port = "2016"
  ec2_instance_ids = ["${aws_instance.ec2[*].id}"]
}

我得到下面的错误

Error: Incorrect attribute value type

  on provisioners/different-box/modules/load-balancer/resources.tf line 109, in resource "aws_alb_target_group_attachment" "alb_target_group_attachment":
 109:   target_id = "${var.ec2_instance_ids[count.index]}"

Inappropriate value for attribute "target_id": string required.

是否有办法避免此错误并将ec2 id传递给列表？

${aws_instance.ec2[*].id}已经是一个id列表，因此如果将其括在方括号中，它将成为一个列表

删除方括号会将其保留为字符串列表，因此在对其进行索引时，会得到一个字符串，这是目标\u id参数所需要的。

${aws\u instance.ec2[*].id}已经是一个id列表，因此将其包装在方括号中会使其成为列表。放下方括号，一切都会好起来的。

resource "aws_alb_target_group_attachment" "alb_target_group_attachment" {
  count = length("${var.ec2_instance_ids}")
  target_group_arn = "${aws_alb_target_group.alb_target_group.arn}"
  target_id = "${var.ec2_instance_ids[count.index]}"
  port = "${var.alb_target_group_port}"
}

module "alb_engine-ui" {
  source = "./modules/load-balancer"
  env = "${lower(var.env)}"
  project = "engine-ui"
  vpc_id = "${data.aws_vpc.main.id}"
  public_subnet1_id = "${var.public_subnet1_id}"
  public_subnet2_id = "${var.public_subnet2_id}"
  health_check_target_group_path = "/"
  certificate_arn = "${var.certificate_arn}"
  alb_target_group_port = "2016"
  ec2_instance_ids = ["${aws_instance.ec2[*].id}"]
}

variable "ec2_instance_ids" {
  description = "the ec2 instance ids to be used for alb target group"
  type = "list"
}

Error: Incorrect attribute value type

  on provisioners/different-box/modules/load-balancer/resources.tf line 109, in resource "aws_alb_target_group_attachment" "alb_target_group_attachment":
 109:   target_id = "${var.ec2_instance_ids[count.index]}"

Inappropriate value for attribute "target_id": string required.