enhancement: Added var to enable HA mode for notification service (#172)

Author: bmonkman

templates/kubernetes/terraform/environments/prod/main.tf

@@ -82,5 +82,6 @@ module "kubernetes" {
   # This domain or address must be verified by the mail provider (Sendgrid, SES, etc.)
   user_auth_mail_from_address = "noreply@${local.domain_name}"
 
-  notification_service_enabled    = <%if eq (index .Params `sendgridApiKey`) "" %>false<% else %>true<% end %>
+  notification_service_enabled          = <%if eq (index .Params `sendgridApiKey`) "" %>false<% else %>true<% end %>
+  notification_service_highly_available = true
 }

templates/kubernetes/terraform/environments/stage/main.tf

@@ -81,5 +81,6 @@ module "kubernetes" {
   # This domain or address must be verified by the mail provider (Sendgrid, SES, etc.)
   user_auth_mail_from_address = "noreply@${local.domain_name}"
 
-  notification_service_enabled    = <%if eq (index .Params `sendgridApiKey`) "" %>false<% else %>true<% end %>
+  notification_service_enabled          = <%if eq (index .Params `sendgridApiKey`) "" %>false<% else %>true<% end %>
+  notification_service_highly_available = false
 }

templates/kubernetes/terraform/modules/kubernetes/notification_service.tf

@@ -32,6 +32,19 @@ resource "helm_release" "notification_service" {
     value = "true"
   }
 
+  set {
+    name  = "autoscaling.enabled"
+    value = var.notification_service_highly_available ? "true" : "false" # If false, deployment replicas will be set to 1 and the replica options below will be ignored
+  }
+  set {
+    name  = "autoscaling.minReplicas"
+    value = var.notification_service_highly_available ? "2" : "1"
+  }
+  set {
+    name  = "autoscaling.maxReplicas"
+    value = var.notification_service_highly_available ? "4" : "2"
+  }
+
   # This will become a secret provided as an env var
   set_sensitive {
     name  = "application.sendgridApiKey"

templates/kubernetes/terraform/modules/kubernetes/variables.tf

@@ -132,6 +132,12 @@ variable "user_auth_mail_from_address" {
 
 variable "notification_service_enabled" {
   description = "If enabled, will install the Zero notification service in the cluster to enable easy implementation of notification via email, sms, push, etc."
-  type        = string
-  default     = "false"
+  type        = bool
+  default     = false
+}
+
+variable "notification_service_highly_available" {
+  description = "If enabled, will make sure a minimum of 2 pods are running and use a horizontal pod autoscaler to make scale the number of pods based on CPU. Recommended for Production."
+  type        = bool
+  default     = true
 }