从本地列表中获取值

Question

我正在尝试使用 terraform 标记 docker swarm 实例 我将变量和局部变量定义为 variables.tf

variable "instance_count" {
  default = "3"
}
variable "instance_type" {
  default = "t2.micro"
}
variable "aws_region" {
  default = "us-east-1"
}
variable "ami" {
  default = "ami-09e67e426f25ce0d7"
}
variable "host_name" {
  type    = map(number)
  default = {
    "Manager" = 1
    "Worker" = 2
  }
}

当我引用此列表的每个值以将其作为标签分配给 ec2 实例时，如下所示 ec2instance.tf

resource "aws_instance" "swarm_instance" {
  count           = var.instance_count
  ami             = var.ami
  instance_type   = var.instance_type
  key_name        = aws_key_pair.dockerswarm.key_name

  tags = {
    Name = "Swarm_Instance-${count.index + 1}"
  }
   tags = {
    Name = "${local.expanded_names}"
  }
locals {
  expanded_names = {
    for name, count in var.host_name : name => [
      for i in range(count) : format("%s-%02d", name, i+1)
    ]
  }
}

Terraform 抱怨 local.expanded_names is object with 2 attributes 我尝试使用${local.expanded_names.value}，但后来它抱怨 object does not have an attribute named "value"。 那么当 terraform 中 value 属性不可用时如何从列表中检索值。

Answer 1

标签应该是字符串，在您的情况下，我会使用jsonencode 从您正在构建的对象中获取字符串，请参阅下面的示例代码

variable "host_name" {
  type    = map(number)
  default = {
    "Manager" = 1
    "Worker" = 2
  }
}

locals {
  expanded_names = jsonencode({
    for name, count in var.host_name : name => [
      for i in range(count) : format("%s-%02d", name, i+1)
    ]
  })
}

provider "aws" {
  region = "us-east-1"
}

resource "aws_instance" "instance" {
  ami           = "ami-1c761163"
  instance_type = "r5.large"

  tags = {
    Terraformed = "true"
    Name        = local.expanded_names
  }
}

如果我们对此进行 terraform 计划，我们会得到以下结果：

Terraform will perform the following actions:

  # aws_instance.instance will be created
  + resource "aws_instance" "instance" {
      + ami                                  = "ami-1c761163"
      ...
      + instance_state                       = (known after apply)
      + instance_type                        = "r5.large"
      ...
      + subnet_id                            = (known after apply)
      + tags                                 = {
          + "Name"        = jsonencode(
                {
                  + Manager = [
                      + "Manager-01",
                    ]
                  + Worker  = [
                      + "Worker-01",
                      + "Worker-02",
                    ]
                }
            )
          + "Terraformed" = "true"
        }

---

或者也许您的意思是创建一个名称数组：

• 经理-01
• 工人-01
• 工人-02

然后将其用作实例名称...如果是这种情况，您的扩展名称不应该是对象{}，而是数组[]，那么我们使用它而不是您的计数，请参见下面的代码示例：

variable "host_name" {
  type    = map(number)
  default = {
    "Manager" = 1
    "Worker" = 2
  }
}

locals {
  expanded_names = flatten([
    for name, count in var.host_name : [
      for i in range(count) : format("%s-%02d", name, i+1)
    ]
  ])
}

provider "aws" {
  region = "us-east-1"
}

resource "aws_instance" "instance" {
  for_each = toset(local.expanded_names)

  ami           = "ami-1c761163"
  instance_type = "r5.large"

  tags = {
    Terraformed = "true"
    Name        = each.value
  }
}

以及关于该输出的 terraform 计划：

Terraform will perform the following actions:

  # aws_instance.instance["Manager-01"] will be created
  + resource "aws_instance" "instance" {
      + ami                                  = "ami-1c761163"
      ...
      + tags                                 = {
          + "Name"        = "Manager-01"
          + "Terraformed" = "true"
        }
      ...
    }

  # aws_instance.instance["Worker-01"] will be created
  + resource "aws_instance" "instance" {
      + ami                                  = "ami-1c761163"
      ...
      + tags                                 = {
          + "Name"        = "Worker-01"
          + "Terraformed" = "true"
        }
      ...
    }

  # aws_instance.instance["Worker-02"] will be created
  + resource "aws_instance" "instance" {
      + ami                                  = "ami-1c761163"
      ...
      + tags                                 = {
          + "Name"        = "Worker-02"
          + "Terraformed" = "true"
        }
      ...
    }

Plan: 3 to add, 0 to change, 0 to destroy.