my_autoscale_rule.tf

data "azurerm_app_service_plan" "test" {
  name                = "devspapptest"
  resource_group_name = "devrgapptest"
}

resource "azurerm_monitor_autoscale_setting" "test" {
  name                = "devspapptest-Autoscale-9680"
  resource_group_name = "devrgapptest"
  location            = "AustraliaEast"
  target_resource_id  = "${data.azurerm_app_service_plan.test.id}"

  profile {
    name = "defaultProfile2"

    capacity {
      default = 1
      minimum = 1
      maximum = 3
    }

    rule {
      metric_trigger {
        metric_name        = "CpuPercentage"
        metric_resource_id = "${data.azurerm_app_service_plan.test.id}"
        statistic          = "Average"
        time_window        = "PT5M"
        time_grain         = "PT5M"
        time_aggregation   = "Average"
        operator           = "GreaterThan"
        threshold          = 60
      }

      scale_action {
        direction = "Increase"
        type      = "ChangeCount"
        value     = "1"
        cooldown  = "PT10M"
      }
    }
  }
}