本地创建Terraform模块引用VPC资源时遇属性不支持错误求助

本地创建Terraform模块，在EC2实例和安全组模块中引用VPC相关资源时无法推进，报错提示module.vpc不存在vpc_id属性。以下是相关代码及错误信息：

EC2模块代码 #

data "aws_ami" "ubuntu" {
  owners      = ["373042721571"]
  most_recent = true

  filter {
    name   = "name"
    values = ["image-test"]
  }
}

# data "template_file" "user_data" {
# template = file("userdata.sh")
# }

resource "aws_instance" "web-1" {
  count                 = 1
  ami                   = "${data.aws_ami.ubuntu.id}"
  instance_type         = "t2.micro"
  key_name              = var.key_name
  subnet_id             = var.subnetid
  vpc_security_group_ids = var.securitygroupid
  associate_public_ip_address = true
  # user_data = data.template_file.user_data.rendered
  tags = {
    Name  = "Server-1"
    Owner = "Terraform"
  }
}

安全组模块代码 #

resource "aws_security_group" "allow_all" {
  name        = var.sg_name
  description = "allowing all traffic to the servers in public "
  vpc_id      = var.vpcid

  ingress {
    from_port        = 0
    to_port          = 0
    protocol         = "-1"
    cidr_blocks      = ["0.0.0.0/0"]
    ipv6_cidr_blocks = ["::/0"]
  }

  egress {
    from_port        = 0
    to_port          = 0
    protocol         = "-1"
    cidr_blocks      = ["0.0.0.0/0"]
    ipv6_cidr_blocks = ["::/0"]
  }

  tags = {
    Name = "allow_all_trafic"
  }
}

根模块调用代码 #

module "vpc" {
  source                    = "./module/vpc"
  vpc_cidr                  = var.vpc_cidr
  vpc_name                  = var.vpc_name
  IGW_name                  = var.IGW_name
  routing_table_public_name = var.routing_table_public_name
}

module "securitygroup" {
  source   = "./module/securitygroup"
  sg_name  = var.sg_name
  vpcid    = module.vpc.vpc_id
}

module "ec2" {
  source           = "./module/ec2"
  key_name         = var.key_name
  securitygroupid  = module.securitygroup.aws_security_group.allow_all.id
  subnetid         = module.vpcmodule.public[0]
}

错误信息 #

│ Error: Unsupported attribute
│
│ on output.tf line 3, in output "vpc_id":
│ 3: value = module.vpc.vpc_id
│ ├────────────────
│ │ module.vpc is a object, known only after apply
│
│ This object does not have an attribute named "vpc_id".

• 给VPC模块添加输出配置
  报错核心是VPC模块未导出vpc_id等属性，需在VPC模块目录下创建outputs.tf，显式导出所需资源属性：

  output "vpc_id" {
    description = "ID of the created VPC"
    value       = aws_vpc.your_vpc_resource.id # 替换为VPC模块中实际的aws_vpc资源名称
  }
  
  output "public_subnets" {
    description = "List of public subnet IDs"
    value       = aws_subnet.public_subnets.*.id # 替换为VPC模块中实际的公网子网资源名称
  }
  

• 修正根模块的子网引用错误
  根模块中EC2的subnetid = module.vpcmodule.public[0]属于拼写错误，应改为：

  subnetid = module.vpc.public_subnets[0]
  

• 修正安全组ID的传递方式
  EC2的vpc_security_group_ids要求传入列表类型，需先在安全组模块添加输出：

  # 安全组模块的outputs.tf
  output "sg_id" {
    description = "ID of the created security group"
    value       = aws_security_group.allow_all.id
  }
  

  再在根模块调用EC2时用列表传递：

  module "ec2" {
    # ...其他参数
    securitygroupid = [module.securitygroup.sg_id]
  }
  

• 验证模块输出
  运行terraform plan前，确保所有模块的输出配置正确，Terraform能识别到导出的属性。

内容的提问来源于stack exchange，提问作者gcn