From 50aede5330ed0a63924217d008aad473b7be946e Mon Sep 17 00:00:00 2001
From: Alexandre Gaillet <alexandre.gaillet@fr.clara.net>
Date: Wed, 21 Mar 2018 12:28:49 +0100
Subject: [PATCH] MON-140 - Added default function to ELB and Api Gateway
 monitors

---
 cloud/aws/apigateway/monitors-api.tf | 16 ++++++++------
 cloud/aws/elb/monitors-elb.tf        | 32 +++++++++++++++++-----------
 2 files changed, 30 insertions(+), 18 deletions(-)

diff --git a/cloud/aws/apigateway/monitors-api.tf b/cloud/aws/apigateway/monitors-api.tf
index f6d2cd9..b25c3d2 100644
--- a/cloud/aws/apigateway/monitors-api.tf
+++ b/cloud/aws/apigateway/monitors-api.tf
@@ -37,9 +37,11 @@ resource "datadog_monitor" "API_http_5xx_errors_count" {
 
   query = <<EOF
     sum(last_5m): (
-      avg:aws.apigateway.5xxerror{${var.filter_tags}} by {region,apiname}.as_count() /
-      (avg:aws.apigateway.count{${var.filter_tags}} by {region,apiname}.as_count() + ${var.artificial_requests_count})
-    ) * 100 > ${var.http_5xx_requests_threshold_critical}
+      default(
+        avg:aws.apigateway.5xxerror{${var.filter_tags}} by {region,apiname}.as_count() /
+        (avg:aws.apigateway.count{${var.filter_tags}} by {region,apiname}.as_count() + ${var.artificial_requests_count}),
+      0) * 100
+    ) > ${var.http_5xx_requests_threshold_critical}
   EOF
 
   evaluation_delay = "${var.delay}"
@@ -69,9 +71,11 @@ resource "datadog_monitor" "API_http_4xx_errors_count" {
 
   query = <<EOF
     sum(last_5m): (
-      avg:aws.apigateway.4xxerror{${var.filter_tags}} by {region,apiname}.as_count() /
-      (avg:aws.apigateway.count{${var.filter_tags}} by {region,apiname}.as_count() + ${var.artificial_requests_count})
-    ) * 100 > ${var.http_4xx_requests_threshold_critical}
+      default(
+        avg:aws.apigateway.4xxerror{${var.filter_tags}} by {region,apiname}.as_count() /
+        (avg:aws.apigateway.count{${var.filter_tags}} by {region,apiname}.as_count() + ${var.artificial_requests_count}),
+      0) * 100
+    ) > ${var.http_4xx_requests_threshold_critical}
   EOF
 
   evaluation_delay = "${var.delay}"
diff --git a/cloud/aws/elb/monitors-elb.tf b/cloud/aws/elb/monitors-elb.tf
index df8cf26..fc12fa5 100644
--- a/cloud/aws/elb/monitors-elb.tf
+++ b/cloud/aws/elb/monitors-elb.tf
@@ -40,9 +40,11 @@ resource "datadog_monitor" "ELB_too_much_4xx" {
 
   query = <<EOF
     avg(last_5m): (
-      avg:aws.elb.httpcode_elb_4xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
-      avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername}
-    ) * 100 > ${var.elb_4xx_threshold_critical}
+      default(
+        avg:aws.elb.httpcode_elb_4xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
+        avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername},
+      0) * 100
+    ) > ${var.elb_4xx_threshold_critical}
   EOF
 
   type = "metric alert"
@@ -74,9 +76,11 @@ resource "datadog_monitor" "ELB_too_much_5xx" {
 
   query = <<EOF
     avg(last_5m): (
-      avg:aws.elb.httpcode_elb_5xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
-      avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername}
-    ) * 100 > ${var.elb_5xx_threshold_critical}
+      default(
+        avg:aws.elb.httpcode_elb_5xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
+        avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername},
+      0) * 100
+    ) > ${var.elb_5xx_threshold_critical}
   EOF
 
   type = "metric alert"
@@ -108,9 +112,11 @@ resource "datadog_monitor" "ELB_too_much_4xx_backend" {
 
   query = <<EOF
     avg(last_5m): (
-      avg:aws.elb.httpcode_backend_4xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
-      avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername}
-    ) * 100 > ${var.elb_backend_4xx_threshold_critical}
+      default(
+        avg:aws.elb.httpcode_backend_4xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
+        avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername},
+      0) * 100
+    ) > ${var.elb_backend_4xx_threshold_critical}
   EOF
 
   type = "metric alert"
@@ -142,9 +148,11 @@ resource "datadog_monitor" "ELB_too_much_5xx_backend" {
 
   query = <<EOF
     avg(last_5m): (
-      avg:aws.elb.httpcode_backend_5xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
-      avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername}
-    ) * 100 > ${var.elb_backend_5xx_threshold_critical}
+      default(
+        avg:aws.elb.httpcode_backend_5xx{${data.template_file.filter.rendered}} by {region,loadbalancername} /
+        avg:aws.elb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancername},
+      0) * 100
+    ) > ${var.elb_backend_5xx_threshold_critical}
   EOF
 
   type = "metric alert"