如何将Terraform模块的Map变量传入Resource实现for_each？

问题核心 #

你当前模块无法获取instance变量的原因是模块内未定义该变量，同时资源配置中存在一处属性取值错误。

步骤1：在模块中定义instance变量 #

在模块目录下创建variables.tf文件，明确声明接收的instance Map变量：

variable "instance" {
  type = map(object({
    instance_hostname = string
    instance_label    = string
    instance_tags     = list(string)
    ssh_key_name      = list(string)
    plan              = string
    os_id             = string
    label             = string
    enable_ipv6       = bool
    backups           = string
    backups_schedule  = string
    backups_dow       = number
    backups_hour      = number
    ddos_protection   = bool
    activation_email  = bool
  }))
  description = "Map of instances to provision"
  default     = {}
}

# 确保模块已定义其他依赖变量，比如region
variable "region" {
  type        = string
  description = "Target region for all instances"
}

步骤2：修正模块内资源的配置错误 #

你的vultr_instance资源中region = each.value.region是错误的——传入的instance Map里并没有region字段，该值是通过模块的region变量传递的，需要改为var.region：

resource "vultr_instance" "my_instance" {
  for_each          = var.instance
  plan              = each.value.plan
  region            = var.region  # 修正此处，使用模块级region变量
  os_id             = each.value.os_id
  label             = each.value.label
  tags              = each.value.instance_tags
  hostname          = each.value.instance_hostname
  firewall_group_id = vultr_firewall_group.firewallgroups.id
  vpc_ids           = [vultr_vpc.vpc.id]
  ssh_key_ids       = [data.vultr_ssh_key.ssh_key.id]
  enable_ipv6       = each.value.enable_ipv6
  ddos_protection   = each.value.ddos_protection
  activation_email  = each.value.activation_email
  backups           = each.value.backups
  backups_schedule {
    type = try(each.value.backups_schedule, null)
    dow  = try(each.value.backups_dow, null)
    hour = try(each.value.backups_hour, null)
  }
}

验证执行 #

完成修改后，执行以下命令确认配置生效：

• terraform init：初始化模块与提供者
• terraform plan：查看执行计划，确认将创建application和database两个实例
• terraform apply：执行资源创建

内容的提问来源于stack exchange，提问作者Rostyslav Malenko