使用 foreach 在多个项目上启用多个 GCP API（不计入）答案

【问题标题】：Enable multiple GCP APIs on multiple Projects with foreach (not count)使用 foreach 在多个项目上启用多个 GCP API（不计入）
【发布时间】：2021-10-20 09:01:05
【问题描述】：

我想在多个项目中启用多个 GCP API。我目前的做法是：

resource "google_project_service" "customer_projects" {                          
   count   = length(var.my_projects) * length(var.apis_customer_projects)
   project = google_project.customer_projects[var.my_projects[floor(count.index / length(var.apis_customer_projects))]].project_id
   service = var.apis_customer_projects[count.index % length(var.apis_customer_projects)]                              
}

var.my_projects 和 var.apis_customer_projects 都包含列表。

但是正如这篇优秀的article 中所描述的，count 有一些缺点，我宁愿使用foreach。

曾经有一个google_project_services（注意复数形式），但目前似乎已被弃用。

【问题讨论】：

标签： loops google-cloud-platform foreach terraform terraform-provider-gcp

【解决方案1】：

根据我的理解，我认为最好的选择是使用 setproduct() 函数循环遍历同一资源中的两个列表变量。

这是 Terraform 文档中的一个示例：

locals {
  # setproduct works with sets and lists, but our variables are both maps
  # so we'll need to convert them first.
  networks = [
    for key, network in var.networks : {
      key        = key
      cidr_block = network.cidr_block
    }
  ]
  subnets = [
    for key, subnet in var.subnets : {
      key    = key
      number = subnet.number
    }
  ]

  network_subnets = [
    # in pair, element zero is a network and element one is a subnet,
    # in all unique combinations.
    for pair in setproduct(local.networks, local.subnets) : {
      network_key = pair[0].key
      subnet_key  = pair[1].key
      network_id  = aws_vpc.example[pair[0].key].id

      # The cidr_block is derived from the corresponding network. See the
      # cidrsubnet function for more information on how this calculation works.
      cidr_block = cidrsubnet(pair[0].cidr_block, 4, pair[1].number)
    }
  ]
}

resource "aws_subnet" "example" {
  # local.network_subnets is a list, so we must now project it into a map
  # where each key is unique. We'll combine the network and subnet keys to
  # produce a single unique key per instance.
  for_each = {
    for subnet in local.network_subnets : "${subnet.network_key}.${subnet.subnet_key}" => subnet
  }

  vpc_id            = each.value.network_id
  availability_zone = each.value.subnet_key
  cidr_block        = each.value.cidr_block
}

参考：https://www.terraform.io/docs/language/functions/setproduct.html#finding-combinations-for-for_each

【讨论】：