将输出变量与terraform一起使用时，“模块的无效输出" [英] 'Not a valid output for module' when using output variable with terraform

问题描述

我正在尝试使用AWS上的Hashicorp Terraform为新项目设置一些IaC.我之所以使用模块，是因为我希望能够在多个环境(分段，生产，开发等)中重用东西

I'm trying to setup some IaC for a new project using Hashicorp Terraform on AWS. I'm using modules because I want to be able to reuse stuff across multiple environments (staging, prod, dev, etc.)

我正在努力了解我必须在一个模块内设置输出变量的位置，以及如何在另一个模块中使用该变量.对此的任何指示将不胜感激！

在创建EC2计算机时，我需要使用在VPC模块中创建的某些东西(子网ID).我的理解是，您无法从另一个模块中的某个模块引用某些内容，因此我尝试使用VPC模块中的输出变量.

I need to use some things created in my VPC module (subnet IDs) when creating EC2 machines. My understanding is that you can't reference something from one module in another, so I am trying to use an output variable from the VPC module.

我的网站main.tf

module "myapp-vpc" {
  source     = "dev/vpc"
  aws_region = "${var.aws_region}"
}

module "myapp-ec2" {
 source     = "dev/ec2"
 aws_region = "${var.aws_region}"
 subnet_id  = "${module.vpc.subnetid"}
}

dev/vpc只需设置一些值并使用我的vpc模块:

dev/vpc simply sets some values and uses my vpc module:

module "vpc" {
  source = "../../modules/vpc"

  aws_region = "${var.aws_region}"

  vpc-cidr            = "10.1.0.0/16"
  public-subnet-cidr  = "10.1.1.0/24"
  private-subnet-cidr = "10.1.2.0/24"
}

在我的vpc main.tf中，在aws_vpc和aws_subnet资源之后(显示子网资源)，我最后有以下内容:

In my vpc main.tf, I have the following at the very end, after the aws_vpc and aws_subnet resources (showing subnet resource):

resource "aws_subnet" "public" {
  vpc_id                  = "${aws_vpc.main.id}"
  map_public_ip_on_launch = true
  availability_zone       = "${var.aws_region}a"
  cidr_block              = "${var.public-subnet-cidr}"
}

output "subnetid" {
  value = "${aws_subnet.public.id}"
}

当我运行terraform plan时，出现以下错误消息:

When I run terraform plan I get the following error message:

错误:模块'vpc':"subnetid"不是模块"vpc"的有效输出

Error: module 'vpc': "subnetid" is not a valid output for module "vpc"

推荐答案

每次都需要显式地将输出传递给每个模块.

Outputs need to be passed up through each module explicitly each time.

例如，如果要从嵌套在另一个模块下面的模块向屏幕输出变量，则需要这样的内容:

For example if you wanted to output a variable to the screen from a module nested below another module you would need something like this:

output "child_foo" {
  value = "foobar"
}

parent-module.tf

module "child" {
  source = "path/to/child"
}

output "parent_foo" {
  value = "${module.child.child_foo}"
}

main.tf

module "parent" {
  source = "path/to/parent"
}

output "main_foo" {
  value = "${module.parent.parent_foo}"
}

这篇关于将输出变量与terraform一起使用时，“模块的无效输出"的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！