chore: Update regions used and switch to explicit secondary replication group variable

Author: bryantbiggs

README.md

@@ -333,11 +333,12 @@ No modules.
 | <a name="input_create_parameter_group"></a> [create\_parameter\_group](#input\_create\_parameter\_group) | Determines whether the ElastiCache parameter group will be created or not | `bool` | `false` | no |
 | <a name="input_create_primary_global_replication_group"></a> [create\_primary\_global\_replication\_group](#input\_create\_primary\_global\_replication\_group) | Determines whether an primary ElastiCache global replication group will be created | `bool` | `false` | no |
 | <a name="input_create_replication_group"></a> [create\_replication\_group](#input\_create\_replication\_group) | Determines whether an ElastiCache replication group will be created or not | `bool` | `true` | no |
+| <a name="input_create_secondary_global_replication_group"></a> [create\_secondary\_global\_replication\_group](#input\_create\_secondary\_global\_replication\_group) | Determines whether an secondary ElastiCache global replication group will be created | `bool` | `false` | no |
 | <a name="input_create_security_group"></a> [create\_security\_group](#input\_create\_security\_group) | Determines if a security group is created | `bool` | `true` | no |
 | <a name="input_create_subnet_group"></a> [create\_subnet\_group](#input\_create\_subnet\_group) | Determines whether the Elasticache subnet group will be created or not | `bool` | `true` | no |
 | <a name="input_data_tiering_enabled"></a> [data\_tiering\_enabled](#input\_data\_tiering\_enabled) | Enables data tiering. Data tiering is only supported for replication groups using the `r6gd` node type. This parameter must be set to true when using `r6gd` nodes | `bool` | `null` | no |
 | <a name="input_description"></a> [description](#input\_description) | User-created description for the replication group | `string` | `null` | no |
-| <a name="input_engine"></a> [engine](#input\_engine) | Name of the cache engine to be used for this cache cluster. Valid values are `memcached` or `redis` | `string` | `null` | no |
+| <a name="input_engine"></a> [engine](#input\_engine) | Name of the cache engine to be used for this cache cluster. Valid values are `memcached` or `redis` | `string` | `"redis"` | no |
 | <a name="input_engine_version"></a> [engine\_version](#input\_engine\_version) | Version number of the cache engine to be used. If not set, defaults to the latest version | `string` | `null` | no |
 | <a name="input_final_snapshot_identifier"></a> [final\_snapshot\_identifier](#input\_final\_snapshot\_identifier) | (Redis only) Name of your final cluster snapshot. If omitted, no final snapshot will be made | `string` | `null` | no |
 | <a name="input_global_replication_group_id"></a> [global\_replication\_group\_id](#input\_global\_replication\_group\_id) | The ID of the global replication group to which this replication group should belong | `string` | `null` | no |

examples/memcached-cluster/main.tf

@@ -5,7 +5,7 @@ provider "aws" {
 data "aws_availability_zones" "available" {}
 
 locals {
-  region = "us-east-1"
+  region = "eu-west-1"
   name   = "ex-${basename(path.cwd)}"
 
   vpc_cidr = "10.0.0.0/16"

examples/redis-cluster-mode/main.tf

@@ -5,7 +5,7 @@ provider "aws" {
 data "aws_availability_zones" "available" {}
 
 locals {
-  region = "us-east-1"
+  region = "eu-west-1"
   name   = "ex-${basename(path.cwd)}"
 
   vpc_cidr = "10.0.0.0/16"

examples/redis-cluster/main.tf

@@ -5,7 +5,7 @@ provider "aws" {
 data "aws_availability_zones" "available" {}
 
 locals {
-  region = "us-east-1"
+  region = "eu-west-1"
   name   = "ex-${basename(path.cwd)}"
 
   vpc_cidr = "10.0.0.0/16"

examples/redis-global-replication-group/main.tf

@@ -63,8 +63,9 @@ module "elasticache_secondary" {
     aws = aws.euwest1
   }
 
-  replication_group_id        = local.name
-  global_replication_group_id = module.elasticache_primary.global_replication_group_id
+  replication_group_id                      = local.name
+  create_secondary_global_replication_group = true
+  global_replication_group_id               = module.elasticache_primary.global_replication_group_id
 
   # Security Group
   vpc_id = module.vpc_secondary.vpc_id

examples/redis-replication-group/main.tf

@@ -5,7 +5,7 @@ provider "aws" {
 data "aws_availability_zones" "available" {}
 
 locals {
-  region = "us-east-1"
+  region = "eu-west-1"
   name   = "ex-${basename(path.cwd)}"
 
   vpc_cidr = "10.0.0.0/16"

main.tf

@@ -53,7 +53,7 @@ resource "aws_elasticache_cluster" "this" {
   snapshot_retention_limit     = local.in_replication_group ? null : var.snapshot_retention_limit
   snapshot_window              = local.in_replication_group ? null : var.snapshot_window
   subnet_group_name            = local.in_replication_group ? null : local.subnet_group_name
-  transit_encryption_enabled   = var.transit_encryption_enabled
+  transit_encryption_enabled   = var.engine == "memcached" ? var.transit_encryption_enabled : null
 
   tags = local.tags
 }
@@ -125,9 +125,8 @@ resource "aws_elasticache_replication_group" "this" {
 ################################################################################
 
 locals {
-  create_global_replication_group = (var.create_primary_global_replication_group || local.create_secondary_global_replication_group)
+  create_global_replication_group = var.create_primary_global_replication_group || var.create_secondary_global_replication_group
 
-  create_secondary_global_replication_group = var.global_replication_group_id != null
 }
 
 resource "aws_elasticache_global_replication_group" "this" {
@@ -147,17 +146,17 @@ resource "aws_elasticache_replication_group" "global" {
   count = var.create && var.create_replication_group && local.create_global_replication_group ? 1 : 0
 
   apply_immediately           = var.apply_immediately
-  at_rest_encryption_enabled  = local.create_secondary_global_replication_group ? null : var.at_rest_encryption_enabled
+  at_rest_encryption_enabled  = var.create_secondary_global_replication_group ? null : var.at_rest_encryption_enabled
   auth_token                  = var.auth_token
   auth_token_update_strategy  = var.auth_token_update_strategy
   auto_minor_version_upgrade  = var.auto_minor_version_upgrade
   automatic_failover_enabled  = var.multi_az_enabled || var.cluster_mode_enabled ? true : var.automatic_failover_enabled
   data_tiering_enabled        = var.data_tiering_enabled
   description                 = coalesce(var.description, "Global replication group")
-  engine                      = local.create_secondary_global_replication_group ? null : var.engine
-  engine_version              = local.create_secondary_global_replication_group ? null : var.engine_version
+  engine                      = var.create_secondary_global_replication_group ? null : var.engine
+  engine_version              = var.create_secondary_global_replication_group ? null : var.engine_version
   final_snapshot_identifier   = var.final_snapshot_identifier
-  global_replication_group_id = local.create_secondary_global_replication_group ? var.global_replication_group_id : null
+  global_replication_group_id = var.create_secondary_global_replication_group ? var.global_replication_group_id : null
   ip_discovery                = var.ip_discovery
   kms_key_id                  = var.at_rest_encryption_enabled ? var.kms_key_arn : null
 
@@ -178,20 +177,20 @@ resource "aws_elasticache_replication_group" "global" {
   node_type                   = var.node_type
   notification_topic_arn      = var.notification_topic_arn
   num_cache_clusters          = var.cluster_mode_enabled ? null : var.num_cache_clusters
-  num_node_groups             = local.create_secondary_global_replication_group ? null : local.num_node_groups
-  parameter_group_name        = local.create_secondary_global_replication_group ? null : local.parameter_group_name_result
+  num_node_groups             = var.create_secondary_global_replication_group ? null : local.num_node_groups
+  parameter_group_name        = var.create_secondary_global_replication_group ? null : local.parameter_group_name_result
   port                        = coalesce(var.port, local.port)
   preferred_cache_cluster_azs = var.preferred_cache_cluster_azs
   replicas_per_node_group     = var.replicas_per_node_group
   replication_group_id        = var.replication_group_id
-  security_group_names        = local.create_secondary_global_replication_group ? null : var.security_group_names
+  security_group_names        = var.create_secondary_global_replication_group ? null : var.security_group_names
   security_group_ids          = local.security_group_ids
-  snapshot_arns               = local.create_secondary_global_replication_group ? null : var.snapshot_arns
-  snapshot_name               = local.create_secondary_global_replication_group ? null : var.snapshot_name
+  snapshot_arns               = var.create_secondary_global_replication_group ? null : var.snapshot_arns
+  snapshot_name               = var.create_secondary_global_replication_group ? null : var.snapshot_name
   snapshot_retention_limit    = var.snapshot_retention_limit
   snapshot_window             = var.snapshot_window
   subnet_group_name           = local.subnet_group_name
-  transit_encryption_enabled  = local.create_secondary_global_replication_group ? null : var.transit_encryption_enabled
+  transit_encryption_enabled  = var.create_secondary_global_replication_group ? null : var.transit_encryption_enabled
   user_group_ids              = var.user_group_ids
 
   tags = local.tags

modules/README.md

@@ -0,0 +1 @@
+# AWS ElastiCache Terraform sub-module(s)

modules/user-group/main.tf

@@ -39,7 +39,7 @@ resource "aws_elasticache_user" "default" {
   user_id              = var.default_user.user_id
   user_name            = "default"
 
-  tags = var.tags
+  tags = local.tags
 }
 
 ################################################################################

variables.tf

@@ -59,7 +59,7 @@ variable "cluster_id" {
 variable "engine" {
   description = "Name of the cache engine to be used for this cache cluster. Valid values are `memcached` or `redis`"
   type        = string
-  default     = null
+  default     = "redis"
 }
 
 variable "engine_version" {
@@ -297,6 +297,12 @@ variable "create_primary_global_replication_group" {
   default     = false
 }
 
+variable "create_secondary_global_replication_group" {
+  description = "Determines whether an secondary ElastiCache global replication group will be created"
+  type        = bool
+  default     = false
+}
+
 ################################################################################
 # Parameter Group
 ################################################################################