feat: Added variable autoscaling_enabled to control autoscaling (#44)

Co-authored-by: Max Williams <[email protected]>

Author: max-rocket-internet

CHANGELOG.md

@@ -2,13 +2,6 @@
 
 All notable changes to this project will be documented in this file.
 
-## [1.2.0](https://github.com/terraform-aws-modules/terraform-aws-dynamodb-table/compare/v1.1.1...v1.2.0) (2022-01-14)
-
-
-### Features
-
-* Added autoscaled table resource (may cause unexpected changes) ([#43](https://github.com/terraform-aws-modules/terraform-aws-dynamodb-table/issues/43)) ([c4a8306](https://github.com/terraform-aws-modules/terraform-aws-dynamodb-table/commit/c4a8306643ad30f67b63b3db37fcf7c8dd5b168a))
-
 ### [1.1.1](https://github.com/terraform-aws-modules/terraform-aws-dynamodb-table/compare/v1.1.0...v1.1.1) (2022-01-10)
 
 

README.md

@@ -29,13 +29,7 @@ module "dynamodb_table" {
 
 **Warning: enabling or disabling autoscaling can cause your table to be recreated**
 
-There are two separate Terraform resources used for the DynamoDB table: one is for when any autoscaling settings are used and the other when not. The following scenarios will make Terraform recreate the table:
-
-- Upgrading from an older version of this module with autoscaling settings enabled
-- Enabling autoscaling settings when they were previously disabled
-- Disabling autoscaling settings when they were previously enabled
-
-In these scenarios you will need to move the old `aws_dynamodb_table` resource that is being `destroyed` to the new resource that is being `created`. For example:
+There are two separate Terraform resources used for the DynamoDB table: one is for when any autoscaling is enabled the other when disabled. If your table is already created and then you change the variable `autoscaling_enabled` then your table will be recreated by Terraform. In this case you will need to move the old `aws_dynamodb_table` resource that is being `destroyed` to the new resource that is being `created`. For example:
 
 ```
 terraform state mv module.dynamodb_table.aws_dynamodb_table.this module.dynamodb_table.aws_dynamodb_table.autoscaled
@@ -86,6 +80,7 @@ No modules.
 |------|-------------|------|---------|:--------:|
 | <a name="input_attributes"></a> [attributes](#input\_attributes) | List of nested attribute definitions. Only required for hash\_key and range\_key attributes. Each attribute has two properties: name - (Required) The name of the attribute, type - (Required) Attribute type, which must be a scalar type: S, N, or B for (S)tring, (N)umber or (B)inary data | `list(map(string))` | `[]` | no |
 | <a name="input_autoscaling_defaults"></a> [autoscaling\_defaults](#input\_autoscaling\_defaults) | A map of default autoscaling settings | `map(string)` | <pre>{<br>  "scale_in_cooldown": 0,<br>  "scale_out_cooldown": 0,<br>  "target_value": 70<br>}</pre> | no |
+| <a name="input_autoscaling_enabled"></a> [autoscaling\_enabled](#input\_autoscaling\_enabled) | Whether or not to enable autoscaling. See note in README about this setting | `bool` | `false` | no |
 | <a name="input_autoscaling_indexes"></a> [autoscaling\_indexes](#input\_autoscaling\_indexes) | A map of index autoscaling configurations. See example in examples/autoscaling | `map(map(string))` | `{}` | no |
 | <a name="input_autoscaling_read"></a> [autoscaling\_read](#input\_autoscaling\_read) | A map of read autoscaling settings. `max_capacity` is the only required key. See example in examples/autoscaling | `map(string)` | `{}` | no |
 | <a name="input_autoscaling_write"></a> [autoscaling\_write](#input\_autoscaling\_write) | A map of write autoscaling settings. `max_capacity` is the only required key. See example in examples/autoscaling | `map(string)` | `{}` | no |

autoscaling.tf

@@ -1,5 +1,5 @@
 resource "aws_appautoscaling_target" "table_read" {
-  count = var.create_table && length(var.autoscaling_read) > 0 ? 1 : 0
+  count = var.create_table && var.autoscaling_enabled && length(var.autoscaling_read) > 0 ? 1 : 0
 
   max_capacity       = var.autoscaling_read["max_capacity"]
   min_capacity       = var.read_capacity
@@ -9,7 +9,7 @@ resource "aws_appautoscaling_target" "table_read" {
 }
 
 resource "aws_appautoscaling_policy" "table_read_policy" {
-  count = var.create_table && length(var.autoscaling_read) > 0 ? 1 : 0
+  count = var.create_table && var.autoscaling_enabled && length(var.autoscaling_read) > 0 ? 1 : 0
 
   name               = "DynamoDBReadCapacityUtilization:${aws_appautoscaling_target.table_read[0].resource_id}"
   policy_type        = "TargetTrackingScaling"
@@ -29,7 +29,7 @@ resource "aws_appautoscaling_policy" "table_read_policy" {
 }
 
 resource "aws_appautoscaling_target" "table_write" {
-  count = var.create_table && length(var.autoscaling_write) > 0 ? 1 : 0
+  count = var.create_table && var.autoscaling_enabled && length(var.autoscaling_write) > 0 ? 1 : 0
 
   max_capacity       = var.autoscaling_write["max_capacity"]
   min_capacity       = var.write_capacity
@@ -39,7 +39,7 @@ resource "aws_appautoscaling_target" "table_write" {
 }
 
 resource "aws_appautoscaling_policy" "table_write_policy" {
-  count = var.create_table && length(var.autoscaling_write) > 0 ? 1 : 0
+  count = var.create_table && var.autoscaling_enabled && length(var.autoscaling_write) > 0 ? 1 : 0
 
   name               = "DynamoDBWriteCapacityUtilization:${aws_appautoscaling_target.table_write[0].resource_id}"
   policy_type        = "TargetTrackingScaling"
@@ -59,7 +59,7 @@ resource "aws_appautoscaling_policy" "table_write_policy" {
 }
 
 resource "aws_appautoscaling_target" "index_read" {
-  for_each = var.create_table ? var.autoscaling_indexes : {}
+  for_each = var.create_table && var.autoscaling_enabled ? var.autoscaling_indexes : {}
 
   max_capacity       = each.value["read_max_capacity"]
   min_capacity       = each.value["read_min_capacity"]
@@ -69,7 +69,7 @@ resource "aws_appautoscaling_target" "index_read" {
 }
 
 resource "aws_appautoscaling_policy" "index_read_policy" {
-  for_each = var.create_table ? var.autoscaling_indexes : {}
+  for_each = var.create_table && var.autoscaling_enabled ? var.autoscaling_indexes : {}
 
   name               = "DynamoDBReadCapacityUtilization:${aws_appautoscaling_target.index_read[each.key].resource_id}"
   policy_type        = "TargetTrackingScaling"
@@ -89,7 +89,7 @@ resource "aws_appautoscaling_policy" "index_read_policy" {
 }
 
 resource "aws_appautoscaling_target" "index_write" {
-  for_each = var.create_table ? var.autoscaling_indexes : {}
+  for_each = var.create_table && var.autoscaling_enabled ? var.autoscaling_indexes : {}
 
   max_capacity       = each.value["write_max_capacity"]
   min_capacity       = each.value["write_min_capacity"]
@@ -99,7 +99,7 @@ resource "aws_appautoscaling_target" "index_write" {
 }
 
 resource "aws_appautoscaling_policy" "index_write_policy" {
-  for_each = var.create_table ? var.autoscaling_indexes : {}
+  for_each = var.create_table && var.autoscaling_enabled ? var.autoscaling_indexes : {}
 
   name               = "DynamoDBWriteCapacityUtilization:${aws_appautoscaling_target.index_write[each.key].resource_id}"
   policy_type        = "TargetTrackingScaling"

examples/autoscaling/main.tf

@@ -9,12 +9,13 @@ resource "random_pet" "this" {
 module "dynamodb_table" {
   source = "../../"
 
-  name           = "my-table-${random_pet.this.id}"
-  hash_key       = "id"
-  range_key      = "title"
-  billing_mode   = "PROVISIONED"
-  read_capacity  = 5
-  write_capacity = 5
+  name                = "my-table-${random_pet.this.id}"
+  hash_key            = "id"
+  range_key           = "title"
+  billing_mode        = "PROVISIONED"
+  read_capacity       = 5
+  write_capacity      = 5
+  autoscaling_enabled = true
 
   autoscaling_read = {
     scale_in_cooldown  = 50

main.tf

@@ -1,11 +1,5 @@
-locals {
-  autoscaling_enabled     = length(var.autoscaling_read) + length(var.autoscaling_write) + length(var.autoscaling_indexes) > 0 ? true : false
-  create_normal_table     = var.create_table && !local.autoscaling_enabled ? 1 : 0
-  create_autoscaled_table = var.create_table && local.autoscaling_enabled ? 1 : 0
-}
-
 resource "aws_dynamodb_table" "this" {
-  count = local.create_normal_table
+  count = var.create_table && !var.autoscaling_enabled ? 1 : 0
 
   name             = var.name
   billing_mode     = var.billing_mode
@@ -88,7 +82,7 @@ resource "aws_dynamodb_table" "this" {
 }
 
 resource "aws_dynamodb_table" "autoscaled" {
-  count = local.create_autoscaled_table
+  count = var.create_table && var.autoscaling_enabled ? 1 : 0
 
   name             = var.name
   billing_mode     = var.billing_mode

variables.tf

@@ -122,6 +122,12 @@ variable "timeouts" {
   }
 }
 
+variable "autoscaling_enabled" {
+  description = "Whether or not to enable autoscaling. See note in README about this setting"
+  type        = bool
+  default     = false
+}
+
 variable "autoscaling_defaults" {
   description = "A map of default autoscaling settings"
   type        = map(string)