Added alarm for splunk s3 backup for delivery failures

Author: robbailiff2

infrastructure/stacks/api-layer/cloudwatch_alarms.tf

@@ -491,3 +491,32 @@ resource "aws_cloudwatch_metric_alarm" "acm_expiry_alarms" {
 
   alarm_actions = [aws_sns_topic.cloudwatch_alarms.arn]
 }
+
+# Splunk backup S3 bucket delivery failure alarm
+resource "aws_cloudwatch_metric_alarm" "splunk_backup_delivery_failure" {
+  alarm_name          = "SplunkBackupS3DeliveryFailure"
+  alarm_description   = "Triggers when there is a delivery failure to the eli-splunk S3 bucket"
+  namespace           = "AWS/S3"
+  metric_name         = "DeliveryFailed"
+  statistic           = "Sum"
+  period              = 300 # 5 minutes
+  evaluation_periods  = 1
+  threshold           = 1
+  comparison_operator = "GreaterThanOrEqualToThreshold"
+  treat_missing_data  = "notBreaching"
+
+  dimensions = {
+    BucketName  = "eli-splunk"
+    StorageType = "AllStorageTypes"
+  }
+
+  alarm_actions = [aws_sns_topic.cloudwatch_alarms.arn]
+
+  tags = {
+    Environment = var.environment
+    AlertType   = "data-delivery"
+    Service     = "s3"
+    Severity    = "high"
+    ManagedBy   = "terraform"
+  }
+}