From 93f408483dc73250e9263603d30a860d679ff8ac Mon Sep 17 00:00:00 2001
From: lzrocha <luizfel@gmail.com>
Date: Tue, 5 Oct 2021 19:54:10 +1100
Subject: [PATCH 1/4] Adding CloudFront CW alarms

---
 _variables.tf                   | 15 ++++++
 cloudwatch-alarms-cloudfront.tf | 87 +++++++++++++++++++++++++++++++++
 2 files changed, 102 insertions(+)
 create mode 100644 cloudwatch-alarms-cloudfront.tf

diff --git a/_variables.tf b/_variables.tf
index 424a1a5..9ece00a 100644
--- a/_variables.tf
+++ b/_variables.tf
@@ -135,4 +135,19 @@ variable "response_page_path" {
 variable "lambda_edge" {
   default     = []
   description = "Lambda EDGE configuration"
+}
+variable "alarms" {
+  type        = map(any)
+  default     = {}
+  description = <<EOF
+The keys of the map are the metric names. This list must be given as a comma-separated string.
+The following arguments are supported:
+  - comparison_operator: GreaterThanOrEqualToThreshold, GreaterThanThreshold, LessThanThreshold, LessThanOrEqualToThreshold
+  - evaluation_periods: The number of periods over which data is compared to the specified threshold.
+  - period: The period in seconds over which the specified statistic is applied.
+  - statistic: The statistic to apply to the alarm's associated metric.
+  - threshold: The number of occurances over a given period.
+  - actions: The actions to execute when the alarm transitions into an ALARM state (ARN). 
+  - ok_actions: The list of actions to execute when this alarm transitions into an OK state from any other state (ARN). 
+EOF
 }
\ No newline at end of file
diff --git a/cloudwatch-alarms-cloudfront.tf b/cloudwatch-alarms-cloudfront.tf
new file mode 100644
index 0000000..ab47bf2
--- /dev/null
+++ b/cloudwatch-alarms-cloudfront.tf
@@ -0,0 +1,87 @@
+variable "default_threshold" {
+  description = "The default threshold for the metric."
+  default     = 5
+}
+
+variable "default_evaluation_periods" {
+  description = "The default amount of evaluation periods."
+  default     = 2
+}
+
+variable "default_period" {
+  description = "The default evaluation period."
+  default     = 60
+}
+
+variable "default_comparison_operator" {
+  description = "The default comparison operator."
+  default     = "GreaterThanOrEqualToThreshold"
+}
+
+variable "default_statistic" {
+  description = "The default statistic."
+  default     = "Average"
+}
+
+resource "aws_cloudwatch_metric_alarm" "alarm" {
+  count = length(var.alarms)
+
+  alarm_name = format("cloudfront-%s-%s",
+    aws_cloudfront_distribution.default[0].id,
+    element(keys(var.alarms), count.index)
+  )
+
+  comparison_operator = lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "comparison_operator",
+    var.default_comparison_operator
+  )
+
+  evaluation_periods = lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "evaluation_periods",
+    var.default_evaluation_periods
+  )
+
+  metric_name = element(keys(var.alarms), count.index)
+
+  namespace = "AWS/CloudFront"
+
+  period = lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "period",
+    var.default_period
+  )
+
+  statistic = lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "statistic",
+    var.default_statistic
+  )
+
+  threshold = lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "threshold",
+    var.default_threshold
+  )
+
+  dimensions = {
+    DistributionId = aws_cloudfront_distribution.default[0].id
+    Region         = "Global"
+  }
+
+  alarm_actions = compact(split(",", lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "actions",
+    ""
+  )))
+
+  ok_actions = compact(split(",", lookup(
+    var.alarms[element(keys(var.alarms), count.index)],
+    "ok_actions",
+    ""
+  )))
+
+  insufficient_data_actions = []
+  treat_missing_data        = "ignore"
+}
\ No newline at end of file

From 23f1a06c99665d052102bed7f067f6cf7c3b845e Mon Sep 17 00:00:00 2001
From: lzrocha <luizfel@gmail.com>
Date: Thu, 7 Oct 2021 11:42:09 +1100
Subject: [PATCH 2/4] Keep variables in the _variables.tf file

---
 _variables.tf                   | 25 +++++++++++++++++++++++++
 cloudwatch-alarms-cloudfront.tf | 25 -------------------------
 2 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/_variables.tf b/_variables.tf
index 9ece00a..b7a5ed8 100644
--- a/_variables.tf
+++ b/_variables.tf
@@ -136,6 +136,31 @@ variable "lambda_edge" {
   default     = []
   description = "Lambda EDGE configuration"
 }
+
+variable "default_threshold" {
+  description = "The default threshold for the metric."
+  default     = 5
+}
+
+variable "default_evaluation_periods" {
+  description = "The default amount of evaluation periods."
+  default     = 2
+}
+
+variable "default_period" {
+  description = "The default evaluation period."
+  default     = 60
+}
+
+variable "default_comparison_operator" {
+  description = "The default comparison operator."
+  default     = "GreaterThanOrEqualToThreshold"
+}
+
+variable "default_statistic" {
+  description = "The default statistic."
+  default     = "Average"
+}
 variable "alarms" {
   type        = map(any)
   default     = {}
diff --git a/cloudwatch-alarms-cloudfront.tf b/cloudwatch-alarms-cloudfront.tf
index ab47bf2..2cf51fd 100644
--- a/cloudwatch-alarms-cloudfront.tf
+++ b/cloudwatch-alarms-cloudfront.tf
@@ -1,28 +1,3 @@
-variable "default_threshold" {
-  description = "The default threshold for the metric."
-  default     = 5
-}
-
-variable "default_evaluation_periods" {
-  description = "The default amount of evaluation periods."
-  default     = 2
-}
-
-variable "default_period" {
-  description = "The default evaluation period."
-  default     = 60
-}
-
-variable "default_comparison_operator" {
-  description = "The default comparison operator."
-  default     = "GreaterThanOrEqualToThreshold"
-}
-
-variable "default_statistic" {
-  description = "The default statistic."
-  default     = "Average"
-}
-
 resource "aws_cloudwatch_metric_alarm" "alarm" {
   count = length(var.alarms)
 

From 0a125c7beed615cf0fc14edd12844d04824acd28 Mon Sep 17 00:00:00 2001
From: lzrocha <luizfel@gmail.com>
Date: Thu, 7 Oct 2021 11:42:51 +1100
Subject: [PATCH 3/4] Updating resource name

---
 cloudwatch-alarms-cloudfront.tf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cloudwatch-alarms-cloudfront.tf b/cloudwatch-alarms-cloudfront.tf
index 2cf51fd..a8cfea0 100644
--- a/cloudwatch-alarms-cloudfront.tf
+++ b/cloudwatch-alarms-cloudfront.tf
@@ -1,4 +1,4 @@
-resource "aws_cloudwatch_metric_alarm" "alarm" {
+resource "aws_cloudwatch_metric_alarm" "cloufront_alarm" {
   count = length(var.alarms)
 
   alarm_name = format("cloudfront-%s-%s",

From 7c7d8c690b257c9fa85d14fce741244e4359f24d Mon Sep 17 00:00:00 2001
From: lzrocha <luizfel@gmail.com>
Date: Thu, 7 Oct 2021 11:43:08 +1100
Subject: [PATCH 4/4] Adding alarm example

---
 examples/cloudfront-simple-alarm.tf | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 examples/cloudfront-simple-alarm.tf

diff --git a/examples/cloudfront-simple-alarm.tf b/examples/cloudfront-simple-alarm.tf
new file mode 100644
index 0000000..2b06648
--- /dev/null
+++ b/examples/cloudfront-simple-alarm.tf
@@ -0,0 +1,24 @@
+resource "aws_s3_bucket" "app_frontend" {
+  bucket_prefix = "my-frontend-app-"
+  acl           = "private"
+}
+
+module "app_frontend" {
+  source = "git::https://github.com/DNXLabs/terraform-aws-static-app.git?ref=2.0.1" # Always check the latest version
+
+  name            = "my-frontend-app"
+  s3_bucket_id    = aws_s3_bucket.app_frontend.id
+  hostnames       = ["www.example.com"]
+  certificate_arn = "arn:aws:acm:us-east-1:<account-id>:certificate/<certificate-hash>" # Replace the <account-id> and <certificate-hash> from a valid certificate
+  hosted_zone     = "example.com"
+  hostname_create = true
+
+  alarms = {
+    "TotalErrorRate" = {
+      threshold = 1 #(%)
+    }
+    "5xxErrorRate" = {
+      threshold = 5 #(%)
+    }
+  }
+}