无法计算Terraform的“计数”值：为什么？

Question

我的模板中具有以下资源规范：

resource "azurerm_sql_firewall_rule" "allow_app_server" {
  count = "${length(split(",", azurerm_app_service.backend.outbound_ip_addresses))}"

  depends_on = ["azurerm_app_service.backend"]

  name                = "${format("Allow App Service Plan %d", count.index)}"
  start_ip_address    = "${element(split(",", azurerm_app_service.backend.possible_outbound_ip_addresses), count.index)}"
  end_ip_address      = "${element(split(",", azurerm_app_service.backend.possible_outbound_ip_addresses), count.index)}"
  resource_group_name = "${var.environment_resource_group_name}"
  server_name         = "${var.db_server_name}"
}

resource "azurerm_app_service" "backend" {
   # properties ommitted for brevity
}

现在，当我运行时terraform plan，消息错误

azurerm_sql_firewall_rule.allow_app_server：无法计算“计数”的值

为什么？我该怎么做才能解决此问题（不需要我部分部署模板）？

Answer 1

您是否尝试过用括号括起来？

resource "azurerm_sql_firewall_rule" "allow_app_server" {
  count = "${length([split(",", azurerm_app_service.backend.outbound_ip_addresses)])}"

  depends_on = ["azurerm_app_service.backend"]

  name                = "${format("Allow App Service Plan %d", count.index)}"
  start_ip_address    = "${element(split(",", azurerm_app_service.backend.possible_outbound_ip_addresses), count.index)}"
  end_ip_address      = "${element(split(",", azurerm_app_service.backend.possible_outbound_ip_addresses), count.index)}"
  resource_group_name = "${var.environment_resource_group_name}"
  server_name         = "${var.db_server_name}"
}

resource "azurerm_app_service" "backend" {
   # properties ommitted for brevity
}
`