make db version a variable

group_vars/all.yml.example

@@ -34,13 +34,14 @@ dns_zone_name: "poa.internal"
 ## All resources will be prefixed with this one
 prefix: "sokol"
 
-## The following settings are related to the RDS instance which will be created during deployment 
+## The following settings are related to the Postgres RDS instance which will be created during deployment 
 db_id: "poa"
 db_username: "username"
 db_password: "qwerty12345"
 db_instance_class: "db.m4.xlarge"
 db_storage: "120"
 db_storage_type: "gp2"
+db_version: "10.5"
 
 ## The following settngs are related to SSL of Application Load Balancer that will be deployed to AWS. If use_ssl is set to false, alb_* variables can be omitted
 use_ssl: "false"

roles/main_infra/defaults/main.yml

@@ -21,6 +21,7 @@ db_password: "qwerty12345"
 db_instance_class: "db.m4.xlarge"
 db_storage: "120"
 db_storage_type: "gp2"
+db_version: "10.5"
 
 alb_ssl_policy: "ELBSecurityPolicy-2016-08"
 alb_certificate_arn: "arn:aws:acm:us-east-1:008312654217:certificate/ce6ec2cb-eba4-4b02-af1d-e77ce8813497"

roles/main_infra/files/rds.tf

@@ -1,7 +1,7 @@
 resource "aws_db_instance" "default" {
   identifier             = "${var.prefix}-${var.db_id}"
   engine                 = "postgres"
-  engine_version         = "10.5"
+  engine_version         = "${var.db_version}"
   instance_class         = "${var.db_instance_class}"
   storage_type           = "${var.db_storage_type}"
   allocated_storage      = "${var.db_storage}"

roles/main_infra/files/variables.tf

@@ -50,6 +50,7 @@ variable "db_password" {}
 variable "db_storage" {}
 variable "db_storage_type" {}
 variable "db_instance_class" {}
+variable "db_version" {}
 
 variable "new_relic_app_name" {}
 variable "new_relic_license_key" {}

roles/main_infra/templates/terraform.tfvars.j2

@@ -16,6 +16,7 @@ db_password           = "{{ db_password }}"
 db_instance_class     = "{{ db_instance_class }}"
 db_storage            = "{{ db_storage }}"
 db_storage_type       = "{{ db_storage_type }}"
+db_version            = "{{ db_version }}"
 
 alb_ssl_policy        = "{{ alb_ssl_policy }}"
 alb_certificate_arn   = "{{ alb_certificate_arn }}"