6-结构化配置完整实例

展示两种写法（把值写在 variables.tf  和 写在 terraform.tfvars）

目录结构

project/
├── main.tf
├── variables.tf
├── outputs.tf

main.tf

terraform {
  required_providers {
    alicloud = {
      source  = "aliyun/alicloud"
      version = ">= 1.200.0"
    }
  }
  required_version = ">= 1.1.0"
}

provider "alicloud" {
  region     = var.region
  access_key = var.access_key
  secret_key = var.secret_key
}

# 创建多台 ECS 实例
resource "alicloud_instance" "ecs" {
  count              = var.ecs_count
  instance_name      = "ecs-${count.index + 1}"
  image_id           = var.image_id
  instance_type      = var.instance_type
  security_groups    = [var.security_group_id]
  vswitch_id         = var.vswitch_id
  internet_max_bandwidth_out = 0
}

# 创建多个 EIP
resource "alicloud_eip" "eip" {
  count               = var.ecs_count
  bandwidth           = 5
  internet_charge_type = "PayByTraffic"
}

# 绑定 EIP 到对应 ECS
resource "alicloud_eip_association" "assoc" {
  count        = var.ecs_count
  instance_id  = alicloud_instance.ecs[count.index].id
  allocation_id = alicloud_eip.eip[count.index].id
}

variables.tf

variable "region" {
  type        = string
  default     = "cn-beijing"
}

variable "access_key" {
  type        = string
  default     = "你的AK"
}

variable "secret_key" {
  type        = string
  default     = "你的SK"
}

variable "ecs_count" {
  type        = number
  default     = 2
}

variable "image_id" {
  type        = string
  default     = "ubuntu_24_04_x64_20G_alibase_20250722.vhd"
}

variable "instance_type" {
  type        = string
  default     = "ecs.t5-lc1m1.small"
}

variable "security_group_id" {
  type        = string
  default     = "sg-xxxxx"
}

variable "vswitch_id" {
  type        = string
  default     = "vsw-xxxxx"
}

outputs.tf

output "private_ips" {
  value = [for i in alicloud_instance.ecs : i.private_ip]
}

output "public_ips" {
  value = [for e in alicloud_eip.eip : e.ip_address]
}

优点：开箱即用。缺点：所有值都“写死”在 variables.tf，不适合多环境。

 

方法二：用 terraform.tfvars 提供实际值（推荐）

目录结构

project/
├── main.tf
├── variables.tf
├── terraform.tfvars
├── outputs.tf

main.tf（跟方法一完全相同）

variables.tf  （只定义，不赋默认值）

variable "region" {
  type        = string
  description = "Region of ECS"
}

variable "access_key" {
  type        = string
  description = "Access key"
}

variable "secret_key" {
  type        = string
  description = "Secret key"
}

variable "ecs_count" {
  type        = number
  description = "Number of ECS instances"
}

variable "image_id" {
  type        = string
  description = "Image ID"
}

variable "instance_type" {
  type        = string
  description = "ECS instance type"
}

variable "security_group_id" {
  type        = string
  description = "Security group ID"
}

variable "vswitch_id" {
  type        = string
  description = "VSwitch ID"
}

terraform.tfvars（放真实值）

region            = "cn-beijing"
access_key        = "你的AK"
secret_key        = "你的SK"
ecs_count         = 2
image_id          = "ubuntu_24_04_x64_20G_alibase_20250722.vhd"
instance_type     = "ecs.t5-lc1m1.small"
security_group_id = "sg-xxxxx"
vswitch_id        = "vsw-xxxxx"

outputs.tf（跟方法一相同）

output "private_ips" {
  value = [for i in alicloud_instance.ecs : i.private_ip]
}

output "public_ips" {
  value = [for e in alicloud_eip.eip : e.ip_address]
}

优点：

1. 变量声明和实际值分离，更清晰。

2. 可以有多个 *.tfvars 文件（比如 dev.tfvars、prod.tfvars），切换环境时只要：

terraform apply -var-file="prod.tfvars"

总结：

1. 如果只是测试/学习，用 方法一（variables.tf 里赋默认值）就行。

2. 如果要多环境（开发、测试、生产），最好用 方法二（terraform.tfvars）。