Terraform 模块依赖关系破坏了 template_file

Posted 2023-03-24

【中文标题】Terraform 模块依赖关系破坏了 template_file

【英文标题】：Terraform module dependency breaks template_file

【发布时间】：2018-02-21 10:46:29

【问题描述】：

不确定这是错误还是我做错了什么。当我在两个模块之间引入依赖关系时，依赖模块的 template_file 数据中的变量会起作用，并且 terraform 抱怨它找不到它。

我有两个模块，saltmaster 和 cassandra。目标是让 saltmaster 通过输出变量公开其 IP 地址，并让 cassandra 使用它。

如果我通过将 IP 地址硬编码为 cassandra 模块的输入来切断模块之间的依赖关系，那么所有资源都会正确创建。但是当我引入依赖时，terraform 会抱怨：

module.cassandra.aws_instance.momentum_cassandra[2]：资源“data.template_file.momentum_cassandra”没有变量“data.template_file.momentum_cassandra.*.vars.hostname”的属性“vars.hostname”

请注意，我在 template_file 的 vars 部分定义了 cassandra 实例的主机名，然后在 aws_instance 的 tags 块中使用它。并且它单独工作正常，但是当 cassandra 模块依赖于 saltmaster 模块时会中断。

cassandra.tf

data "template_file" "momentum_cassandra" 
  count    = "$var.instance_count"
  template = "$file("$path.module/userdata.sh")"

  vars 
    hostname   = "$format("%s%02d", var.name, count.index + 1)"
    saltmaster = "$var.saltmaster"
    salt_installtype = "$var.salt_installtype"
    seed       = "$count.index == 0 ? "true" : "false""
    datacenter = "$var.datacenter"
    rack       = "$var.rack"
  


resource "aws_instance" "momentum_cassandra" 
  count                  = 3
  provider               = "aws.us_dev"
  ami                    = "$var.ami"
  instance_type          = "$var.instance_type"
  key_name               = "$var.instance_key_name"
  subnet_id              = "$element(var.vpc_subnet_ids, count.index)"
  iam_instance_profile   = "$var.iam_instance_profile"

  vpc_security_group_ids = ["$aws_security_group.momentum_cassandra.id"]
  user_data              = "$data.template_file.momentum_cassandra.*.rendered[count.index]"

  lifecycle 
    ignore_changes = ["ami", "user_data"]
  
  tags 
    Name        = "$data.template_file.momentum_cassandra.*.vars.hostname[count.index]"

main.tf

module "cassandra" 
  source = "./tf-aws-momentum-cassandra"
  saltmaster = "$module.saltmaster.private_ip"

saltmaster.tf

# create the userdata for bootstrapping
data "template_file" "saltmaster_userdata" 
  count    = "$var.instance_count"
  template = "$file("$path.module/userdata.sh")"

  vars 
    hostname   = "$format("%s%02d", var.name, count.index + 1)"
    saltmaster = "localhost"
    environment = "$var.environment"
    installtype = "$var.installtype"
  

# create the salt master
resource "aws_instance" "momentum_salt_master" 
  provider               = "aws.us_dev"
  ami                    = "$var.ami"
  instance_type          = "$var.instance_type"
  key_name               = "$var.instance_key_name"
  vpc_security_group_ids = ["$aws_security_group.momentum_salt_master.id"]
  subnet_id              = "$element(var.vpc_subnet_ids, count.index)"
  iam_instance_profile   = "$var.iam_instance_profile"
  user_data              = "$element(data.template_file.saltmaster_userdata.*.rendered, count.index)"


  tags 
    Name        = "$element(data.template_file.saltmaster_userdata.*.vars.hostname, count.index)"
    Environment = "$var.environment"
    Application = "$var.application"
    Role        = "SaltMaster"
  

  root_block_device 
    volume_type           = "gp2"
    volume_size           = 40
    delete_on_termination = true
  


output "private_ip" 
  value = "$aws_instance.momentum_salt_master.private_ip"

【问题讨论】：

你也可以展示你的saltmaster 模块吗？

你以前读过这个吗？ github.com/hashicorp/terraform/issues/…

@ydaetskcoR 我已经用我的 saltmaster 模块的内容更新了我的问题。

【参考方案1】：

根据您使用的 terraform 版本，这可能已修复 here，但是，请尝试替换

"$data.template_file.momentum_cassandra.*.rendered[count.index]"
"$data.template_file.momentum_cassandra.*.vars.hostname[count.index]"

在cassandra.tf 和element 查找

"$element(data.template_file.momentum_cassandra.*.rendered, count.index)"
"$element(data.template_file.momentum_cassandra.*.vars.hostname, count.index)"

你在saltmaster.tf中实际使用的