a2/terraform/modules/common/instance_template/variables.tf

/**
 * Copyright 2022 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
*/

variable "disk_size_gb" {
  description = <<-EOT
    The size of the image in gigabytes for the boot disk of each instance.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#disk_size_gb), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--boot-disk-size).
    EOT
  type        = number
}

variable "disk_type" {
  description = <<-EOT
    The GCE disk type for the boot disk of each instance.

    Possible values: `["pd-ssd", "local-ssd", "pd-balanced", "pd-standard"]`

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#disk_type), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--boot-disk-type).
    EOT
  type        = string
}

variable "machine_image" {
  description = <<-EOT
    The image with which this disk will initialize.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#source_image).

    ------------
    `machine_image.family`

    The family of images from which the latest non-deprecated image will be selected. Conflicts with `machine_image.name`.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/data-sources/compute_image#name), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--image-family).

    ------------
    `machine_image.name`

    The name of a specific image. Conflicts with `machine_image.family`.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/data-sources/compute_image#name), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--image).

    ------------
    `machine_image.project`

    The project_id to which this image belongs.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/data-sources/compute_image#project), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--image-project).
    EOT
  type = object({
    family  = string
    name    = string
    project = string
  })

  validation {
    condition = (
      var.machine_image != null
      // project is non-empty
      && alltrue([
        for empty in [null, ""]
        : var.machine_image.project != empty
      ])
      // at least one is non-empty
      && anytrue([
        for value in [var.machine_image.name, var.machine_image.family]
        : alltrue([for empty in [null, ""] : value != empty])
      ])
      // at least one is empty
      && anytrue([
        for value in [var.machine_image.name, var.machine_image.family]
        : anytrue([for empty in [null, ""] : value == empty])
      ])
    )
    error_message = "project must be non-empty exactly one of family or name must be non-empty"
  }
}

variable "machine_type" {
  description = <<-EOT
    The name of a Google Compute Engine machine type. There are [many possible values](https://cloud.google.com/compute/docs/machine-resource).

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#machine_type), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--machine-type).
    EOT
  type        = string

  validation {
    condition     = var.machine_type != null
    error_message = "must not be null"
  }
}

variable "maintenance_interval" {
  description = <<-EOT
  Specifies the frequency of planned maintenance events. 'PERIODIC' is th only supported value for maintenance_interval.

  Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#maintenance_interval).
    EOT
  type        = string
  validation {
    condition = var.maintenance_interval != null ? contains(
      ["PERIODIC"],
      var.maintenance_interval,
    ) : true
    error_message = "'PERIODIC' is th only supported value for maintenance_interval."
  }
}

variable "use_compact_placement_policy" {
  description = <<-EOT
    The flag to create and use a superblock level compact placement policy for the instances. Currently GCE supports using only 1 placement policy.
    
    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#resource_policies).
    EOT
  type        = bool
  default     = false
}

variable "metadata" {
  description = <<-EOT
    Metadata key/value pairs to make available from within instances created from this template.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#metadata), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--metadata).
    EOT
  type        = map(string)
}

variable "labels" {
  description = <<-EOT
    A set of key/value label pairs to assign to instances created from this template.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#labels), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--labels).
    EOT
  type        = map(string)
}

variable "project_id" {
  description = <<-EOT
    The ID of the project in which the resource belongs.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#project).
    EOT
  type        = string

  validation {
    condition     = var.project_id != null
    error_message = "must not be null"
  }
}

variable "region" {
  description = <<-EOT
    An instance template is a global resource that is not bound to a zone or a region. However, you can still specify some regional resources in an instance template, which restricts the template to the region where that resource resides. For example, a custom subnetwork resource is tied to a specific region.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#region).
    EOT
  type        = string

  validation {
    condition     = var.region != null
    error_message = "must not be null"
  }
}

variable "resource_prefix" {
  description = "Arbitrary string with which all names of newly created resources will be prefixed."
  type        = string

  validation {
    condition     = var.resource_prefix != null
    error_message = "must not be null"
  }
}

variable "use_static_naming" {
  description = <<-EOT
    Flag to determine whether to use static naming for instance_template name. If used static naming, then instance_template cannot be updated. it needs to be destroyed and then recreated.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#name_prefix).
    EOT
  type        = bool
  default     = false

  validation {
    condition     = var.use_static_naming != null
    error_message = "must not be null"
  }
}

variable "service_account" {
  description = <<-EOT
    Service account to attach to the instance.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#service_account).

    ------------
    `service_account.email`

    The service account e-mail address. If not given, the default Google Compute Engine service account is used.

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#email), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--service-account).

    ------------
    `service_account.scopes`

    A list of service scopes. Both OAuth2 URLs and gcloud short names are supported. To allow full access to all Cloud APIs, use the `"cloud-platform"` scope. See a complete list of scopes [here](https://cloud.google.com/sdk/gcloud/reference/alpha/compute/instances/set-scopes#--scopes).

    Related docs: [terraform](https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_instance_template#scopes), [gcloud](https://cloud.google.com/sdk/gcloud/reference/compute/instance-templates/create#--scopes).
    EOT
  type = object({
    email  = string,
    scopes = set(string)
  })
}

variable "startup_script" {
  description = <<-EOT
    Script to run at boot on each instance. This is here for convenience and will just be appended to `metadata` under the key `"startup-script"`.
    EOT
  type        = string
}

variable "subnetwork_self_link" {
  description = "The subnet self-link for the host VPC."
  type        = string

  validation {
    condition     = var.subnetwork_self_link != null
    error_message = "must not be null"
  }
}

variable "network_self_link" {
  description = "The network self-link for the host VPC."
  type        = string

  validation {
    condition     = var.network_self_link != null
    error_message = "must not be null"
  }
}