allow dynamic logging configuration in prometheus

Author: minaslater

aws/telemetry/main.tf

@@ -23,6 +23,7 @@ module "prometheus_workspace" {
   alert_resolve_timeout       = var.alert_resolve_timeout
   alert_subject_template      = var.alert_subject_template
   alertmanager_config_enabled = var.alertmanager_config_enabled
+  logging_group_name          = var.logging_group_name
   name                        = var.prometheus_workspace_name
   tags                        = var.tags
 

aws/telemetry/modules/prometheus-workspace/main.tf

@@ -1,6 +1,18 @@
 resource "aws_prometheus_workspace" "this" {
   alias = var.name
   tags  = var.tags
+
+  dynamic logging_configuration {
+    for_each = var.logging_group_name
+    content {
+    log_group_arn = data.aws_cloudwatch_log_group.this.arn
+    }
+  }
+}
+
+data "aws_cloudwatch_log_group" "this" {
+  count = var.logging_group_name ? 1 : 0
+  name = var.logging_group_name
 }
 
 resource "aws_iam_role" "ingestion" {

aws/telemetry/modules/prometheus-workspace/variables.tf

@@ -28,6 +28,11 @@ variable "alertmanager_config_enabled" {
   default     = true
 }
 
+variable "logging_group_name" {
+  description = "Name of Cloudwatch logging group for Prometheus workspace"
+  type        = string
+}
+
 variable "name" {
   description = "Name for this Prometheus workspace"
   type        = string

aws/telemetry/variables.tf

@@ -46,6 +46,11 @@ variable "alertmanager_config_enabled" {
   default     = true
 }
 
+variable "logging_group_name" {
+  description = "Name of Cloudwatch logging group for Prometheus workspace"
+  type        = string
+}
+
 variable "grafana_role_name" {
   description = "Name of the IAM role created for Grafana"
   type        = string