Update number of background tasks (#3364)

- We want to ensure we have 2 tasks for availability reasons
- Make a variable that is easy to tune without config changes

Author: TheOneFromNorway

terraform/app/autoscaling.tf

@@ -1,8 +1,8 @@
 resource "aws_appautoscaling_target" "ecs_target" {
   count              = var.enable_autoscaling ? 1 : 0
   resource_id        = "service/${aws_ecs_cluster.cluster.name}/${module.web_service.service.name}"
-  max_capacity       = var.maximum_replicas
-  min_capacity       = var.minimum_replicas
+  max_capacity       = var.maximum_web_replicas
+  min_capacity       = var.minimum_web_replicas
   service_namespace  = "ecs"
   scalable_dimension = "ecs:service:DesiredCount"
 }

terraform/app/ecs.tf

@@ -36,7 +36,7 @@ resource "aws_ecs_service" "service" {
   name                              = "mavis-${var.environment}"
   cluster                           = aws_ecs_cluster.cluster.id
   task_definition                   = aws_ecs_task_definition.task_definition.arn
-  desired_count                     = var.minimum_replicas
+  desired_count                     = var.minimum_web_replicas
   launch_type                       = "FARGATE"
   enable_execute_command            = true
   health_check_grace_period_seconds = 60
@@ -152,7 +152,7 @@ module "web_service" {
   cluster_id            = aws_ecs_cluster.cluster.id
   environment           = var.environment
   server_type           = "web"
-  desired_count         = var.minimum_replicas
+  desired_count         = var.minimum_web_replicas
   deployment_controller = "CODE_DEPLOY"
 }
 
@@ -177,5 +177,5 @@ module "good_job_service" {
   cluster_id    = aws_ecs_cluster.cluster.id
   environment   = var.environment
   server_type   = "good-job"
-  desired_count = 1
+  desired_count = var.minimum_good_job_replicas
 }

terraform/app/env/copilotmigration.tfvars

@@ -20,5 +20,5 @@ enable_splunk                   = false
 enable_cis2                     = false
 enable_pds_enqueue_bulk_updates = false
 
-minimum_replicas = 3
-appspec_bucket   = "nhse-mavis-appspec-bucket-copilotmigration"
+appspec_bucket        = "nhse-mavis-appspec-bucket-copilotmigration"
+minimnum_web_replicas = 2

terraform/app/env/poc.tfvars

@@ -15,4 +15,5 @@ http_hosts = {
   MAVIS__HOST                        = "poc.mavistesting.com"
   MAVIS__GIVE_OR_REFUSE_CONSENT_HOST = "poc.mavistesting.com"
 }
-appspec_bucket = "nhse-mavis-appspec-bucket-poc"
+appspec_bucket        = "nhse-mavis-appspec-bucket-poc"
+minimnum_web_replicas = 2

terraform/app/env/preview.tfvars

@@ -24,6 +24,5 @@ http_hosts = {
   MAVIS__GIVE_OR_REFUSE_CONSENT_HOST = "preview.mavistesting.com"
 }
 
-minimum_replicas = 3
-appspec_bucket   = "nhse-mavis-appspec-bucket-preview"
+appspec_bucket              = "nhse-mavis-appspec-bucket-preview"
 ecs_initial_lb_target_group = "green"

terraform/app/env/production.tfvars

@@ -20,7 +20,6 @@ http_hosts = {
   MAVIS__GIVE_OR_REFUSE_CONSENT_HOST = "www.give-or-refuse-consent-for-vaccinations.nhs.uk"
 }
 
-minimum_replicas        = 3
 appspec_bucket          = "nhse-mavis-appspec-bucket-production"
 account_id              = 820242920762
 vpc_log_retention_days  = 14

terraform/app/env/qa.tfvars

@@ -22,5 +22,4 @@ http_hosts = {
   MAVIS__HOST                        = "qa.mavistesting.com"
   MAVIS__GIVE_OR_REFUSE_CONSENT_HOST = "qa.mavistesting.com"
 }
-minimum_replicas = 3
-appspec_bucket   = "nhse-mavis-appspec-bucket-qa"
+appspec_bucket = "nhse-mavis-appspec-bucket-qa"

terraform/app/env/test.tfvars

@@ -19,5 +19,4 @@ http_hosts = {
   MAVIS__HOST                        = "test.mavistesting.com"
   MAVIS__GIVE_OR_REFUSE_CONSENT_HOST = "test.mavistesting.com"
 }
-minimum_replicas = 3
-appspec_bucket   = "nhse-mavis-appspec-bucket-test"
+appspec_bucket = "nhse-mavis-appspec-bucket-test"

terraform/app/env/training.tfvars

@@ -26,5 +26,4 @@ http_hosts = {
   MAVIS__HOST                        = "training.manage-vaccinations-in-schools.nhs.uk"
   MAVIS__GIVE_OR_REFUSE_CONSENT_HOST = "training.give-or-refuse-consent-for-vaccinations.nhs.uk"
 }
-minimum_replicas = 3
-appspec_bucket   = "nhse-mavis-appspec-bucket-training"
+appspec_bucket = "nhse-mavis-appspec-bucket-training"

terraform/app/iam_policy_documents.tf

@@ -49,13 +49,13 @@ data "aws_iam_policy_document" "shell_access" {
 
 data "aws_iam_policy_document" "ecs_secrets_access" {
   statement {
-    sid       = "railsKeySid"
-    actions   = ["ssm:GetParameters"]
+    sid     = "railsKeySid"
+    actions = ["ssm:GetParameters"]
     resources = [
       "arn:aws:ssm:${var.region}:${var.account_id}:parameter${var.rails_master_key_path}",
       aws_ssm_parameter.pds_wait_between_jobs.arn
     ]
-    effect    = "Allow"
+    effect = "Allow"
   }
   statement {
     sid     = "dbSecretSid"