Add possibility to set billing mode for DynamoDB tables (#30)

* Add possibility to set billing mode for DynamoDB tables

* Updated README.md

Co-authored-by: Maxim Mironenko <simixido@gmail.com>
Co-authored-by: actions-bot <58130806+actions-bot@users.noreply.github.com>

README.md

@@ -161,6 +161,7 @@ Available targets:
 | acl | The canned ACL to apply to the S3 bucket | string | `private` | no |
 | additional_tag_map | Additional tags for appending to each tag map | map(string) | `<map>` | no |
 | attributes | Additional attributes (e.g. `state`) | list(string) | `<list>` | no |
+| billing_mode | DynamoDB billing mode | string | `PROVISIONED` | no |
 | block_public_acls | Whether Amazon S3 should block public ACLs for this bucket | bool | `true` | no |
 | block_public_policy | Whether Amazon S3 should block public bucket policies for this bucket | string | `true` | no |
 | context | Default context to use for passing state between label invocations | object | `<map>` | no |

docs/terraform.md

@@ -5,6 +5,7 @@
 | acl | The canned ACL to apply to the S3 bucket | string | `private` | no |
 | additional_tag_map | Additional tags for appending to each tag map | map(string) | `<map>` | no |
 | attributes | Additional attributes (e.g. `state`) | list(string) | `<list>` | no |
+| billing_mode | DynamoDB billing mode | string | `PROVISIONED` | no |
 | block_public_acls | Whether Amazon S3 should block public ACLs for this bucket | bool | `true` | no |
 | block_public_policy | Whether Amazon S3 should block public bucket policies for this bucket | string | `true` | no |
 | context | Default context to use for passing state between label invocations | object | `<map>` | no |

main.tf

@@ -133,8 +133,9 @@ module "dynamodb_table_label" {
 resource "aws_dynamodb_table" "with_server_side_encryption" {
   count          = var.enable_server_side_encryption ? 1 : 0
   name           = module.dynamodb_table_label.id
-  read_capacity  = var.read_capacity
-  write_capacity = var.write_capacity
+  billing_mode   = var.billing_mode
+  read_capacity  = var.billing_mode == "PROVISIONED" ? var.read_capacity : null
+  write_capacity = var.billing_mode == "PROVISIONED" ? var.write_capacity : null
 
   # https://www.terraform.io/docs/backends/types/s3.html#dynamodb_table
   hash_key = "LockID"
@@ -149,6 +150,7 @@ resource "aws_dynamodb_table" "with_server_side_encryption" {
 
   lifecycle {
     ignore_changes = [
+      billing_mode,
       read_capacity,
       write_capacity,
     ]
@@ -165,8 +167,9 @@ resource "aws_dynamodb_table" "with_server_side_encryption" {
 resource "aws_dynamodb_table" "without_server_side_encryption" {
   count          = var.enable_server_side_encryption ? 0 : 1
   name           = module.dynamodb_table_label.id
-  read_capacity  = var.read_capacity
-  write_capacity = var.write_capacity
+  billing_mode   = var.billing_mode
+  read_capacity  = var.billing_mode == "PROVISIONED" ? var.read_capacity : null
+  write_capacity = var.billing_mode == "PROVISIONED" ? var.write_capacity : null
 
   # https://www.terraform.io/docs/backends/types/s3.html#dynamodb_table
   hash_key = "LockID"
@@ -177,6 +180,7 @@ resource "aws_dynamodb_table" "without_server_side_encryption" {
 
   lifecycle {
     ignore_changes = [
+      billing_mode,
       read_capacity,
       write_capacity,
     ]

variables.tf

@@ -93,6 +93,11 @@ variable "acl" {
   default     = "private"
 }
 
+variable "billing_mode" {
+  default     = "PROVISIONED"
+  description = "DynamoDB billing mode"
+}
+
 variable "read_capacity" {
   default     = 5
   description = "DynamoDB read capacity units"