feat: expose spend_basis for budget alerts (#681)

* add optional argument spend_basis to budget alert configuration

* fmt main.tf

* tmf and make generate doc

* force pull request

* regenerate README

Co-authored-by: Bharath KKB <bharathkrishnakb@gmail.com>

README.md

@@ -122,6 +122,7 @@ determining that location is as follows:
 | bucket\_ula | Enable Uniform Bucket Level Access | `bool` | `true` | no |
 | bucket\_versioning | Enable versioning for a GCS bucket to create (optional) | `bool` | `false` | no |
 | budget\_alert\_pubsub\_topic | The name of the Cloud Pub/Sub topic where budget related messages will be published, in the form of `projects/{project_id}/topics/{topic_id}` | `string` | `null` | no |
+| budget\_alert\_spend\_basis | The type of basis used to determine if spend has passed the threshold | `string` | `"CURRENT_SPEND"` | no |
 | budget\_alert\_spent\_percents | A list of percentages of the budget to alert on when threshold is exceeded | `list(number)` | <pre>[<br>  0.5,<br>  0.7,<br>  1<br>]</pre> | no |
 | budget\_amount | The amount to use for a budget alert | `number` | `null` | no |
 | budget\_display\_name | The display name of the budget. If not set defaults to `Budget For <projects[0]|All Projects>` | `string` | `null` | no |

main.tf

@@ -93,6 +93,7 @@ module "budget" {
   billing_account                  = var.billing_account
   amount                           = var.budget_amount
   alert_spent_percents             = var.budget_alert_spent_percents
+  alert_spend_basis                = var.budget_alert_spend_basis
   alert_pubsub_topic               = var.budget_alert_pubsub_topic
   monitoring_notification_channels = var.budget_monitoring_notification_channels
   display_name                     = var.budget_display_name != null ? var.budget_display_name : null

modules/budget/README.md

@@ -21,6 +21,7 @@ module "project_myproject" {
 | Name | Description | Type | Default | Required |
 |------|-------------|------|---------|:--------:|
 | alert\_pubsub\_topic | The name of the Cloud Pub/Sub topic where budget related messages will be published, in the form of `projects/{project_id}/topics/{topic_id}` | `string` | `null` | no |
+| alert\_spend\_basis | The type of basis used to determine if spend has passed the threshold | `string` | `"CURRENT_SPEND"` | no |
 | alert\_spent\_percents | A list of percentages of the budget to alert on when threshold is exceeded | `list(number)` | <pre>[<br>  0.5,<br>  0.7,<br>  1<br>]</pre> | no |
 | amount | The amount to use as the budget | `number` | n/a | yes |
 | billing\_account | ID of the billing account to set a budget on | `string` | n/a | yes |

modules/budget/main.tf

@@ -58,6 +58,7 @@ resource "google_billing_budget" "budget" {
     for_each = var.alert_spent_percents
     content {
       threshold_percent = threshold_rules.value
+      spend_basis       = var.alert_spend_basis
     }
   }
 

modules/budget/variables.tf

@@ -59,6 +59,12 @@ variable "alert_spent_percents" {
   default     = [0.5, 0.7, 1.0]
 }
 
+variable "alert_spend_basis" {
+  description = "The type of basis used to determine if spend has passed the threshold"
+  type        = string
+  default     = "CURRENT_SPEND"
+}
+
 variable "alert_pubsub_topic" {
   description = "The name of the Cloud Pub/Sub topic where budget related messages will be published, in the form of `projects/{project_id}/topics/{topic_id}`"
   type        = string

variables.tf

@@ -241,6 +241,12 @@ variable "budget_alert_spent_percents" {
   default     = [0.5, 0.7, 1.0]
 }
 
+variable "budget_alert_spend_basis" {
+  description = "The type of basis used to determine if spend has passed the threshold"
+  type        = string
+  default     = "CURRENT_SPEND"
+}
+
 variable "budget_labels" {
   description = "A single label and value pair specifying that usage from only this set of labeled resources should be included in the budget."
   type        = map(string)