Terraform 嵌套 for 循环产生意外结果

Question

鉴于此模块输入：

variable "port_mapping_metadata" {
  type = map(object({
    target_type                       = optional(string, "instance")
    ssl_policy                        = optional(string)
    listener_cert_arn                 = optional(string)
    additional_SNI_listener_cert_arns = optional(list(string),[])
    ...

我正在尝试为

port_mapping_metadata

中的每个项目（如果不为空）创建一个资源（如果不为空，则键可能在资源中重复）。因此对于以下输入：additional_SNI_listener_cert_arns

我期望以下 for_each 结果：

  "bar" = {
    vpc_name            = "foo"
    name                = "bar"
    type                = "application"
    port_mapping_metadata = {
      "forward" = {
        instance_names                    = ["inst"]
        listener_cert_arn                 = "arn:aws:acm:us-east-1:1234:certificate/abcd"
        additional_SNI_listener_cert_arns = ["arn:aws:acm:us-east-1:1234:certificate/defg", "arn:aws:acm:us-east-1:1234:certificate/hijk"]
  "bax" = {
    vpc_name            = "foo"
    name                = "bax"
    type                = "application"
    port_mapping_metadata = {
      "forward" = {
        instance_names                    = ["inst2"]
        listener_cert_arn                 = "arn:aws:acm:us-east-1:1234:certificate/abcd"
        additional_SNI_listener_cert_arns = ["arn:aws:acm:us-east-1:1234:certificate/zle"]
(under another key)
  "bar" = {
    vpc_name            = "foo"
    name                = "bar"
    type                = "application"
    port_mapping_metadata = {
      "forward" = {
        instance_names                    = ["inst"]
        listener_cert_arn                 = "arn:aws:acm:us-east-1:1234:certificate/abcd"

我尝试使用 for_each 编写资源，如下所示：

{
  "bar-0" = "arn:aws:acm:us-east-1:1234:certificate/defg"
  "bar-1" = "arn:aws:acm:us-east-1:1234:certificate/hijk"
  "bax-0" = "arn:aws:acm:us-east-1:1234:certificate/zle"
}

但由于某种原因我收到错误：

resource "aws_lb_listener_certificate" "additional_SNI_listener_certs" {
  for_each = {
    for k, v in var.port_mapping_metadata : k => {
      for index, cert_arn in try(v.additional_SNI_listener_cert_arns, []) : "${k}-${index}" => cert_arn
    }
    if try(v.additional_SNI_listener_cert_arns, []) != [] && try(v.additional_SNI_listener_cert_arns, null) != null
  }
  ##this _should_ be "{ "listener_name-0" = "arn1" , ... }"

  listener_arn   = aws_lb_listener.all[element(split("-", each.key), 0)].arn ##this should be "listener_name"
  certificate_arn = each.value ##this should be "arn1"
}

我不明白为什么资源中的

│ Error: Incorrect attribute value type
│ 
│   on .terraform/modules/load_balancer/load_balancer.tf line 235, in resource "aws_lb_listener_certificate" "additional_SNI_listener_certs":
│  235:   certificate_arn = each.value
│     ├────────────────
│     │ each.value is object with no attributes
│ 
│ Inappropriate value for attribute "certificate_arn": string required.

不是单个字符串

each.value

。我确信我错过了一些简单的东西，但我不知道它是什么。也欢迎任何其他方式来做到这一点。

Answer 1

arn1

正在获取以下地图作为输入。但是，您必须通过添加 terraform 输出来打印表达式的结果来验证它。

for_each

现在根据您的要求，将以下地图输入到

{
  bar = {
    "bar-0" = "arn:aws:acm:us-east-1:1234:certificate/defg"
    "bar-1" = "arn:aws:acm:us-east-1:1234:certificate/hijk"
  }
  bax = {
    "bax-0" = "arn:aws:acm:us-east-1:1234:certificate/zle"
  }
}

for_each

需要将代码修改为以下

{
  "bar-0" = "arn:aws:acm:us-east-1:1234:certificate/defg"
  "bar-1" = "arn:aws:acm:us-east-1:1234:certificate/hijk"
  "bax-0" = "arn:aws:acm:us-east-1:1234:certificate/zle"
}

此外，正如我之前建议的那样，添加 

locals {

  original_for_each_expr = {
    for k, v in var.port_mapping_metadata : k => {
      for index, cert_arn in try(v.additional_SNI_listener_cert_arns, []) : "${k}-${index}" => cert_arn
    }
    if try(v.additional_SNI_listener_cert_arns, []) != [] && try(v.additional_SNI_listener_cert_arns, null) != null
  }

  desired_for_each_expr = zipmap(
    flatten(
      [ for i in local.original_for_each_expr : keys(i) ]
    ),
    flatten(
      [ for i in local.original_for_each_expr : values(i) ]
    )
  ) 

}

resource "aws_lb_listener_certificate" "additional_SNI_listener_certs" {
  for_each = local.desired_for_each_expr
  ...
}

来查看是否从表达式中获取所需的值并将其传递给

terraform outputs

。for_each