Add settings for autoscaling to Bigtable module.

modules/bigtable-instance/README.md

@@ -6,10 +6,12 @@ This module allows managing a single BigTable instance, including access configu
 
 - [ ] support bigtable_gc_policy
 - [ ] support bigtable_app_profile
+- [ ] support cluster replicas
+- [ ] support IAM for tables
 
 ## Examples
 
-### Simple instance with access configuration
+### Instance with access configuration
 
 ```hcl
 
@@ -32,24 +34,84 @@ module "bigtable-instance" {
 }
 # tftest modules=1 resources=4
 ```
+
+### Instance with static number of nodes
+
+If you are not using autoscaling settings, you must set a specific number of nodes with the variable `num_nodes`.
+
+```hcl
+
+module "bigtable-instance" {
+  source     = "./fabric/modules/bigtable-instance"
+  project_id = "my-project"
+  name       = "instance"
+  cluster_id = "instance"
+  zone       = "europe-west1-b"
+  num_nodes  = 5
+}
+# tftest modules=1 resources=1
+```
+
+### Instance with autoscaling (based on CPU only)
+
+If you use autoscaling, you should not set the variable `num_nodes`.
+
+```hcl
+
+module "bigtable-instance" {
+  source             = "./fabric/modules/bigtable-instance"
+  project_id         = "my-project"
+  name               = "instance"
+  cluster_id         = "instance"
+  zone               = "europe-southwest1-b"
+  autoscaling_config = {
+    min_nodes  = 3
+    max_nodes  = 7
+    cpu_target = 70
+  }
+}
+# tftest modules=1 resources=1
+```
+
+### Instance with autoscaling (based on CPU and/or storage)
+
+```hcl
+
+module "bigtable-instance" {
+  source             = "./fabric/modules/bigtable-instance"
+  project_id         = "my-project"
+  name               = "instance"
+  cluster_id         = "instance"
+  zone               = "europe-southwest1-a"
+  storage_type       = "SSD"
+  autoscaling_config = {
+    min_nodes      = 3
+    max_nodes      = 7
+    cpu_target     = 70
+    storage_target = 4096
+  }
+}
+# tftest modules=1 resources=1
+```
 <!-- BEGIN TFDOC -->
 
 ## Variables
 
 | name | description | type | required | default |
 |---|---|:---:|:---:|:---:|
-| [name](variables.tf#L45) | The name of the Cloud Bigtable instance. | <code>string</code> | ✓ |  |
-| [project_id](variables.tf#L56) | Id of the project where datasets will be created. | <code>string</code> | ✓ |  |
-| [zone](variables.tf#L88) | The zone to create the Cloud Bigtable cluster in. | <code>string</code> | ✓ |  |
-| [cluster_id](variables.tf#L17) | The ID of the Cloud Bigtable cluster. | <code>string</code> |  | <code>&#34;europe-west1&#34;</code> |
-| [deletion_protection](variables.tf#L23) | Whether or not to allow Terraform to destroy the instance. Unless this field is set to false in Terraform state, a terraform destroy or terraform apply that would delete the instance will fail. | <code></code> |  | <code>true</code> |
-| [display_name](variables.tf#L28) | The human-readable display name of the Bigtable instance. | <code></code> |  | <code>null</code> |
-| [iam](variables.tf#L33) | IAM bindings for topic in {ROLE => [MEMBERS]} format. | <code>map&#40;list&#40;string&#41;&#41;</code> |  | <code>&#123;&#125;</code> |
-| [instance_type](variables.tf#L39) | (deprecated) The instance type to create. One of 'DEVELOPMENT' or 'PRODUCTION'. | <code>string</code> |  | <code>null</code> |
-| [num_nodes](variables.tf#L50) | The number of nodes in your Cloud Bigtable cluster. | <code>number</code> |  | <code>1</code> |
-| [storage_type](variables.tf#L61) | The storage type to use. | <code>string</code> |  | <code>&#34;SSD&#34;</code> |
-| [table_options_defaults](variables.tf#L67) | Default option of tables created in the BigTable instance. | <code title="object&#40;&#123;&#10;  split_keys    &#61; list&#40;string&#41;&#10;  column_family &#61; string&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code title="&#123;&#10;  split_keys    &#61; &#91;&#93;&#10;  column_family &#61; null&#10;&#125;">&#123;&#8230;&#125;</code> |
-| [tables](variables.tf#L79) | Tables to be created in the BigTable instance, options can be null. | <code title="map&#40;object&#40;&#123;&#10;  split_keys    &#61; list&#40;string&#41;&#10;  column_family &#61; string&#10;&#125;&#41;&#41;">map&#40;object&#40;&#123;&#8230;&#125;&#41;&#41;</code> |  | <code>&#123;&#125;</code> |
+| [name](variables.tf#L56) | The name of the Cloud Bigtable instance. | <code>string</code> | ✓ |  |
+| [project_id](variables.tf#L67) | Id of the project where datasets will be created. | <code>string</code> | ✓ |  |
+| [zone](variables.tf#L99) | The zone to create the Cloud Bigtable cluster in. | <code>string</code> | ✓ |  |
+| [autoscaling_config](variables.tf#L17) | Settings for autoscaling of the instance. If you set this variable, the variable num_nodes is ignored. | <code title="object&#40;&#123;&#10;  min_nodes      &#61; number&#10;  max_nodes      &#61; number&#10;  cpu_target     &#61; number,&#10;  storage_target &#61; optional&#40;number, null&#41;&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code>null</code> |
+| [cluster_id](variables.tf#L28) | The ID of the Cloud Bigtable cluster. | <code>string</code> |  | <code>&#34;europe-west1&#34;</code> |
+| [deletion_protection](variables.tf#L34) | Whether or not to allow Terraform to destroy the instance. Unless this field is set to false in Terraform state, a terraform destroy or terraform apply that would delete the instance will fail. | <code></code> |  | <code>true</code> |
+| [display_name](variables.tf#L39) | The human-readable display name of the Bigtable instance. | <code></code> |  | <code>null</code> |
+| [iam](variables.tf#L44) | IAM bindings for topic in {ROLE => [MEMBERS]} format. | <code>map&#40;list&#40;string&#41;&#41;</code> |  | <code>&#123;&#125;</code> |
+| [instance_type](variables.tf#L50) | (deprecated) The instance type to create. One of 'DEVELOPMENT' or 'PRODUCTION'. | <code>string</code> |  | <code>null</code> |
+| [num_nodes](variables.tf#L61) | The number of nodes in your Cloud Bigtable cluster. This value is ignored if you are using autoscaling. | <code>number</code> |  | <code>1</code> |
+| [storage_type](variables.tf#L72) | The storage type to use. | <code>string</code> |  | <code>&#34;SSD&#34;</code> |
+| [table_options_defaults](variables.tf#L78) | Default option of tables created in the BigTable instance. | <code title="object&#40;&#123;&#10;  split_keys    &#61; list&#40;string&#41;&#10;  column_family &#61; string&#10;&#125;&#41;">object&#40;&#123;&#8230;&#125;&#41;</code> |  | <code title="&#123;&#10;  split_keys    &#61; &#91;&#93;&#10;  column_family &#61; null&#10;&#125;">&#123;&#8230;&#125;</code> |
+| [tables](variables.tf#L90) | Tables to be created in the BigTable instance, options can be null. | <code title="map&#40;object&#40;&#123;&#10;  split_keys    &#61; list&#40;string&#41;&#10;  column_family &#61; string&#10;&#125;&#41;&#41;">map&#40;object&#40;&#123;&#8230;&#125;&#41;&#41;</code> |  | <code>&#123;&#125;</code> |
 
 ## Outputs
 

modules/bigtable-instance/main.tf

@@ -18,6 +18,7 @@ locals {
   tables = {
     for k, v in var.tables : k => v != null ? v : var.table_options_defaults
   }
+  num_nodes = var.autoscaling_config == null ? var.num_nodes : null
 }
 
 resource "google_bigtable_instance" "default" {
@@ -27,6 +28,16 @@ resource "google_bigtable_instance" "default" {
     cluster_id   = var.cluster_id
     zone         = var.zone
     storage_type = var.storage_type
+    num_nodes    = local.num_nodes
+    dynamic "autoscaling_config" {
+      for_each = var.autoscaling_config == null ? [] : [""]
+      content {
+        min_nodes      = var.autoscaling_config.min_nodes
+        max_nodes      = var.autoscaling_config.max_nodes
+        cpu_target     = var.autoscaling_config.cpu_target
+        storage_target = var.autoscaling_config.storage_target
+      }
+    }
   }
   instance_type = var.instance_type
 
@@ -56,8 +67,4 @@ resource "google_bigtable_table" "default" {
       family = each.value.column_family
     }
   }
-
-  # lifecycle {
-  #   prevent_destroy = true
-  # }
 }

modules/bigtable-instance/variables.tf

@@ -14,6 +14,17 @@
  * limitations under the License.
  */
 
+variable "autoscaling_config" {
+  description = "Settings for autoscaling of the instance. If you set this variable, the variable num_nodes is ignored."
+  type = object({
+    min_nodes      = number
+    max_nodes      = number
+    cpu_target     = number,
+    storage_target = optional(number, null)
+  })
+  default = null
+}
+
 variable "cluster_id" {
   description = "The ID of the Cloud Bigtable cluster."
   type        = string
@@ -48,7 +59,7 @@ variable "name" {
 }
 
 variable "num_nodes" {
-  description = "The number of nodes in your Cloud Bigtable cluster."
+  description = "The number of nodes in your Cloud Bigtable cluster. This value is ignored if you are using autoscaling."
   type        = number
   default     = 1
 }