VIA-345 SB Scale out fake API based on CPU utilisation.

Author: acerathereinspirative-nhs-nvir

infrastructure/environments/test/fake-api/modules/ecs-service/main.tf

@@ -225,3 +225,21 @@ resource "aws_appautoscaling_policy" "scale_down" {
     }
   }
 }
+
+resource "aws_appautoscaling_policy" "cpu_scaling" {
+  name               = "${var.name}-cpu-scaling"
+  policy_type        = "TargetTrackingScaling"
+  resource_id        = aws_appautoscaling_target.main.resource_id
+  scalable_dimension = aws_appautoscaling_target.main.scalable_dimension
+  service_namespace  = aws_appautoscaling_target.main.service_namespace
+
+  target_tracking_scaling_policy_configuration {
+    target_value       = var.cpu_target
+    scale_out_cooldown = var.cpu_target_scale_out_cooldown
+    scale_in_cooldown  = var.cpu_target_scale_in_cooldown
+
+    predefined_metric_specification {
+      predefined_metric_type = "ECSServiceAverageCPUUtilization"
+    }
+  }
+}

infrastructure/environments/test/fake-api/modules/ecs-service/variables.tf

@@ -90,7 +90,7 @@ variable "min_capacity" {
 variable "max_capacity" {
   description = "The maximum number of tasks for the service."
   type        = number
-  default     = 5
+  default     = 16
 }
 variable "scale_up_threshold_ms" {
   description = "The average response time in milliseconds to trigger a scale-up event."
@@ -102,3 +102,18 @@ variable "scale_down_threshold_ms" {
   type        = number
   default     = 200
 }
+variable "cpu_target" {
+  description = "Target CPU utilization percentage"
+  type        = number
+  default     = 75
+}
+variable "cpu_target_scale_out_cooldown" {
+  description = "Seconds to wait before another CPU target scale-out activity"
+  type        = number
+  default     = 30
+}
+variable "cpu_target_scale_in_cooldown" {
+  description = "Seconds to wait before another CPU target scale-in activity"
+  type        = number
+  default     = 300
+}