From bf327b6464322929b0b3d995825916b3d2246012 Mon Sep 17 00:00:00 2001
From: Boris Rousseau <boris.rousseau@fr.clara.net>
Date: Thu, 22 Mar 2018 09:54:06 +0100
Subject: [PATCH] MON-142: updated based on PR comments + best practices

---
 databases/mysql/README.md    |  4 ++--
 databases/mysql/inputs.tf    | 28 ++++++++++++++++++----------
 databases/mysql/mon-mysql.tf | 32 ++++++++++++++++++++------------
 3 files changed, 40 insertions(+), 24 deletions(-)

diff --git a/databases/mysql/README.md b/databases/mysql/README.md
index ab67fd3..5485210 100644
--- a/databases/mysql/README.md
+++ b/databases/mysql/README.md
@@ -31,8 +31,8 @@ Inputs
 | filter_tags | Tags used for custom filtering | string | `*` | no |
 | mysql_connection_threshold_critical | Maximum critical acceptable percent of connections | string | `80` | no |
 | mysql_connection_threshold_warning | Maximum warning acceptable percent of connections | string | `70` | no |
-| mysql_thread_threshold_critical | Maximum critical acceptable percent of threads | string | `500` | no |
-| mysql_thread_threshold_warning | Maximum warning acceptable percent of threads | string | `400` | no |
+| mysql_thread_threshold_critical | Maximum critical acceptable number of threads | string | `500` | no |
+| mysql_thread_threshold_warning | Maximum warning acceptable number of threads | string | `400` | no |
 | message | Message sent when a monitor is triggered | string | - | yes |
 
 Related documentation
diff --git a/databases/mysql/inputs.tf b/databases/mysql/inputs.tf
index a751d76..2c73edd 100644
--- a/databases/mysql/inputs.tf
+++ b/databases/mysql/inputs.tf
@@ -3,19 +3,27 @@ variable "environment" {
   type        = "string"
 }
 
-variable "filter_tags" {
-  description = "Tags used for filtering"
-  default     = "*"
-}
-
-variable "delay" {
-  default = 900
+# Global DataDog
+variable "evaluation_delay" {
+  description = "Delay in seconds for the metric evaluation"
+  default     = 900
 }
 
 variable "message" {
-  description = "Message sent when a monitor is triggered"
+  description = "Message sent when an alert is triggered"
 }
 
+variable "filter_tags_use_defaults" {
+  description = "Use default filter tags convention"
+  default     = "true"
+}
+
+variable "filter_tags_custom" {
+  description = "Tags used for custom filtering when filter_tags_use_defaults is false"
+  default     = "*"
+}
+
+# MySQL specific
 #################################
 ###   MySQL connections       ###
 #################################
@@ -36,10 +44,10 @@ variable "mysql_connection_threshold_warning" {
 
 variable "mysql_thread_threshold_critical" {
   default     = 500
-  description = "Maximum critical acceptable percent of threads"
+  description = "Maximum critical acceptable number of threads"
 }
 
 variable "mysql_thread_threshold_warning" {
   default     = 400
-  description = "Maximum critical acceptable percent of threads"
+  description = "Maximum critical acceptable number of threads"
 }
diff --git a/databases/mysql/mon-mysql.tf b/databases/mysql/mon-mysql.tf
index 957704a..67f9b3e 100644
--- a/databases/mysql/mon-mysql.tf
+++ b/databases/mysql/mon-mysql.tf
@@ -1,4 +1,12 @@
-resource "datadog_monitor" "mysql_cpu_80_15min" {
+data "template_file" "filter" {
+  template = "$${filter}"
+
+  vars {
+    filter = "${var.filter_tags_use_defaults == "true" ? format("dd_monitoring:enabled,dd_mysql:enabled,env:%s", var.environment) : "${var.filter_tags_custom}"}"
+  }
+}
+
+resource "datadog_monitor" "mysql_connections_15min" {
   name    = "[${var.environment}] Mysql Connections > {{#is_alert}}{{threshold}}%{{/is_alert}}{{#is_warning}}{{warn_threshold}}%{{/is_warning}} ({{value}}%)"
   message = "${var.message}"
   type    = "query alert"
@@ -10,23 +18,23 @@ resource "datadog_monitor" "mysql_cpu_80_15min" {
     ) * 100 > ${var.mysql_connection_threshold_critical}
   EOF
 
-  evaluation_delay = "${var.delay}"
-  new_host_delay   = "${var.delay}"
+  evaluation_delay = "${var.evaluation_delay}"
+  new_host_delay   = "${var.evaluation_delay}"
 
   thresholds {
     warning  = "${var.mysql_connection_threshold_warning}"
     critical = "${var.mysql_connection_threshold_critical}"
   }
 
-  notify_no_data      = false          # Will NOT notify when no data is received
-  evaluation_delay    = "${var.delay}"
+  notify_no_data      = true
+  evaluation_delay    = "${var.evaluation_delay}"
   renotify_interval   = 60
   notify_audit        = false
   timeout_h           = 0
   include_tags        = true
-  locked              = false
+  locked              = true
   require_full_window = true
-  new_host_delay      = "${var.delay}"
+  new_host_delay      = "${var.evaluation_delay}"
   no_data_timeframe   = 20
 
   tags = ["env:${var.environment}", "resource:mysql"]
@@ -44,23 +52,23 @@ resource "datadog_monitor" "mysql_thread_5min" {
     ) > ${var.mysql_thread_threshold_critical}
   EOF
 
-  evaluation_delay = "${var.delay}"
-  new_host_delay   = "${var.delay}"
+  evaluation_delay = "${var.evaluation_delay}"
+  new_host_delay   = "${var.evaluation_delay}"
 
   thresholds {
     warning  = "${var.mysql_thread_threshold_warning}"
     critical = "${var.mysql_thread_threshold_critical}"
   }
 
-  notify_no_data      = false          # Will NOT notify when no data is received
-  evaluation_delay    = "${var.delay}"
+  notify_no_data      = true
+  evaluation_delay    = "${var.evaluation_delay}"
   renotify_interval   = 60
   notify_audit        = false
   timeout_h           = 0
   include_tags        = true
   locked              = false
   require_full_window = true
-  new_host_delay      = "${var.delay}"
+  new_host_delay      = "${var.evaluation_delay}"
   no_data_timeframe   = 20
 
   tags = ["env:${var.environment}", "resource:mysql"]