CCM-14044 Adding Event Alarms

eslint.config.mjs

@@ -20,17 +20,6 @@ import unicorn from 'eslint-plugin-unicorn';
 import { defineConfig, globalIgnores } from 'eslint/config';
 import tseslint from 'typescript-eslint';
 
-import { FlatCompat } from '@eslint/eslintrc';
-import { dirname } from 'node:path';
-import { fileURLToPath } from 'node:url';
-
-const __filename = fileURLToPath(import.meta.url);
-const __dirname = dirname(__filename);
-
-const compat = new FlatCompat({
-  baseDirectory: __dirname,
-});
-
 export default defineConfig([
   globalIgnores([
     '**/*/coverage/*',

infrastructure/terraform/components/nudge/README.md

@@ -20,7 +20,11 @@
 | <a name="input_aws_account_id"></a> [aws\_account\_id](#input\_aws\_account\_id) | The AWS Account ID (numeric) | `string` | n/a | yes |
 | <a name="input_component"></a> [component](#input\_component) | The variable encapsulating the name of this component | `string` | `"nudge"` | no |
 | <a name="input_default_tags"></a> [default\_tags](#input\_default\_tags) | A map of default tags to apply to all taggable resources within the component | `map(string)` | `{}` | no |
+| <a name="input_enable_event_anomaly_detection"></a> [enable\_event\_anomaly\_detection](#input\_enable\_event\_anomaly\_detection) | Enable CloudWatch anomaly detection alarm for inbound event queue message reception | `bool` | `true` | no |
 | <a name="input_environment"></a> [environment](#input\_environment) | The name of the tfscaffold environment | `string` | n/a | yes |
+| <a name="input_event_anomaly_band_width"></a> [event\_anomaly\_band\_width](#input\_event\_anomaly\_band\_width) | The width of the anomaly detection band. Higher values (e.g. 4-6) reduce sensitivity and noise, lower values (e.g. 2-3) increase sensitivity. Recommended: 2-4. | `number` | `3` | no |
+| <a name="input_event_anomaly_evaluation_periods"></a> [event\_anomaly\_evaluation\_periods](#input\_event\_anomaly\_evaluation\_periods) | Number of evaluation periods for the anomaly alarm. Each period is defined by event\_anomaly\_period. | `number` | `2` | no |
+| <a name="input_event_anomaly_period"></a> [event\_anomaly\_period](#input\_event\_anomaly\_period) | The period in seconds over which the specified statistic is applied for anomaly detection. Minimum 300 seconds (5 minutes). Recommended: 300-600. | `number` | `300` | no |
 | <a name="input_eventbus_account_id"></a> [eventbus\_account\_id](#input\_eventbus\_account\_id) | The AWS Account ID for the event bus | `string` | n/a | yes |
 | <a name="input_force_destroy"></a> [force\_destroy](#input\_force\_destroy) | Flag to force deletion of S3 buckets | `bool` | `false` | no |
 | <a name="input_force_lambda_code_deploy"></a> [force\_lambda\_code\_deploy](#input\_force\_lambda\_code\_deploy) | If the lambda package in s3 has the same commit id tag as the terraform build branch, the lambda will not update automatically. Set to True if making changes to Lambda code from on the same commit for example during development | `bool` | `false` | no |

infrastructure/terraform/components/nudge/cloudwatch_metric_alarm_inbound_event_subscriber_anomaly.tf

@@ -0,0 +1,40 @@
+resource "aws_cloudwatch_metric_alarm" "inbound_event_subscriber_anomaly" {
+  count = var.enable_event_anomaly_detection ? 1 : 0
+
+  alarm_name          = "${local.csi}-inbound-event-subscriber-anomaly"
+  alarm_description   = "ANOMALY: Detects anomalous patterns in messages received from the inbound event queue"
+  comparison_operator = "LessThanLowerOrGreaterThanUpperThreshold"
+  evaluation_periods  = var.event_anomaly_evaluation_periods
+  threshold_metric_id = "ad1"
+  treat_missing_data  = "notBreaching"
+
+  metric_query {
+    id          = "m1"
+    return_data = true
+
+    metric {
+      metric_name = "NumberOfMessagesReceived"
+      namespace   = "AWS/SQS"
+      period      = var.event_anomaly_period
+      stat        = "Sum"
+
+      dimensions = {
+        QueueName = module.sqs_inbound_event.sqs_queue_name
+      }
+    }
+  }
+
+  metric_query {
+    id          = "ad1"
+    expression  = "ANOMALY_DETECTION_BAND(m1, ${var.event_anomaly_band_width})"
+    label       = "NumberOfMessagesReceived (expected)"
+    return_data = true
+  }
+
+  tags = merge(
+    var.default_tags,
+    {
+      Name = "${local.csi}-inbound-event-subscriber-anomaly"
+    }
+  )
+}

infrastructure/terraform/components/nudge/variables.tf

@@ -133,3 +133,36 @@ variable "force_destroy" {
   description = "Flag to force deletion of S3 buckets"
   default     = false
 }
+
+##
+# CloudWatch Anomaly Detection Variables
+##
+
+variable "enable_event_anomaly_detection" {
+  type        = bool
+  description = "Enable CloudWatch anomaly detection alarm for inbound event queue message reception"
+  default     = true
+}
+
+variable "event_anomaly_evaluation_periods" {
+  type        = number
+  description = "Number of evaluation periods for the anomaly alarm. Each period is defined by event_anomaly_period."
+  default     = 2
+}
+
+variable "event_anomaly_period" {
+  type        = number
+  description = "The period in seconds over which the specified statistic is applied for anomaly detection. Minimum 300 seconds (5 minutes). Recommended: 300-600."
+  default     = 300
+}
+
+variable "event_anomaly_band_width" {
+  type        = number
+  description = "The width of the anomaly detection band. Higher values (e.g. 4-6) reduce sensitivity and noise, lower values (e.g. 2-3) increase sensitivity. Recommended: 2-4."
+  default     = 3
+
+  validation {
+    condition     = var.event_anomaly_band_width >= 2 && var.event_anomaly_band_width <= 10
+    error_message = "Band width must be between 2 and 10"
+  }
+}