Stop creating empty parameter groups for Elasticache and use default (#140)

Author: vandrijevik

aws/elasticache/main.tf

@@ -5,7 +5,6 @@ locals {
 locals {
   cluster_name                  = "${var.name}-${var.env}"
   family                        = "${var.engine}${local.version_major_minor_only}"
-  parameter_group_name          = var.parameter_group_name != "" ? var.parameter_group_name : "${local.cluster_name}-params${replace(local.version_major_minor_only, ".", "")}"
   port                          = var.port != "" ? var.port : var.engine == "redis" ? "6379" : "11211"
   elasticache_replication_group = var.force_replication_group || var.num_nodes != 1
   cluster_tags = merge(
@@ -27,7 +26,6 @@ resource "aws_elasticache_cluster" "mod" {
   maintenance_window   = var.maintenance_window
   node_type            = var.node_type
   port                 = local.port
-  parameter_group_name = local.parameter_group_name
   security_group_ids   = [aws_security_group.sg_on_elasticache_instance.id]
   subnet_group_name    = aws_elasticache_subnet_group.mod.name
 
@@ -44,7 +42,6 @@ resource "aws_elasticache_replication_group" "mod" {
   maintenance_window            = var.maintenance_window
   node_type                     = var.node_type
   number_cache_clusters         = var.num_nodes
-  parameter_group_name          = aws_elasticache_parameter_group.mod[0].id
   port                          = local.port
   replication_group_description = "${var.name} ${var.env} ${var.engine} instance"
   replication_group_id          = local.cluster_name
@@ -55,17 +52,6 @@ resource "aws_elasticache_replication_group" "mod" {
   tags = local.cluster_tags
 }
 
-resource "aws_elasticache_parameter_group" "mod" {
-  count       = var.create_parameter_group ? 1 : 0
-  name        = local.parameter_group_name
-  family      = local.family
-  description = "${var.name} ${var.env} env ${var.engine} cluster param group"
-
-  lifecycle {
-    create_before_destroy = true
-  }
-}
-
 resource "aws_elasticache_subnet_group" "mod" {
   name        = "${local.cluster_name}-${var.engine}-subnet"
   description = "${local.cluster_name}-${var.engine}-subnet"

aws/elasticache/variables.tf

@@ -7,11 +7,6 @@ variable "automatic_failover_enabled" {
   description = "(Optional) Specifies whether a read-only replica will be automatically promoted to read/write primary if the existing primary fails. If true, Multi-AZ is enabled for this replication group. If false, Multi-AZ is disabled for this replication group. Must be enabled for Redis (cluster mode enabled) replication groups. Defaults to false."
 }
 
-variable "create_parameter_group" {
-  default     = true
-  description = "Create a parameter group in this module"
-}
-
 variable "engine" {
   description = "redis, memcache, etc."
 }
@@ -43,11 +38,6 @@ variable "num_nodes" {
   default = 1
 }
 
-variable "parameter_group_name" {
-  description = "Name of a parameter group to use with the Elasticache instance."
-  default     = ""
-}
-
 variable "port" {
   default = ""
 }