feat: Add the capability to disable alert manager creation (#20)

Author: FlawlessByte

README.md

@@ -12,6 +12,7 @@ module "prometheus" {
 
   workspace_alias = "example"
 
+  create_alert_manager     = true
   alert_manager_definition = <<-EOT
   alertmanager_config: |
     route:
@@ -83,6 +84,7 @@ No modules.
 |------|-------------|------|---------|:--------:|
 | <a name="input_alert_manager_definition"></a> [alert\_manager\_definition](#input\_alert\_manager\_definition) | The alert manager definition that you want to be applied. See more in the [AWS Docs](https://docs.aws.amazon.com/prometheus/latest/userguide/AMP-alert-manager.html) | `string` | `"alertmanager_config: |\n  route:\n    receiver: 'default'\n  receivers:\n    - name: 'default'\n"` | no |
 | <a name="input_create"></a> [create](#input\_create) | Determines whether a resources will be created | `bool` | `true` | no |
+| <a name="input_create_alert_manager"></a> [create\_alert\_manager](#input\_create\_alert\_manager) | Controls whether an Alert Manager definition is created along with the AMP workspace | `bool` | `true` | no |
 | <a name="input_create_workspace"></a> [create\_workspace](#input\_create\_workspace) | Determines whether a workspace will be created or to use an existing workspace | `bool` | `true` | no |
 | <a name="input_kms_key_arn"></a> [kms\_key\_arn](#input\_kms\_key\_arn) | The ARN of the KMS Key to for encryption at rest | `string` | `null` | no |
 | <a name="input_logging_configuration"></a> [logging\_configuration](#input\_logging\_configuration) | The logging configuration of the prometheus workspace. | `map(string)` | `{}` | no |

examples/complete/main.tf

@@ -19,6 +19,7 @@ module "prometheus" {
     log_group_arn = "${aws_cloudwatch_log_group.this.arn}:*"
   }
 
+  create_alert_manager     = true
   alert_manager_definition = <<-EOT
   alertmanager_config: |
     route:

main.tf

@@ -28,7 +28,7 @@ resource "aws_prometheus_workspace" "this" {
 ################################################################################
 
 resource "aws_prometheus_alert_manager_definition" "this" {
-  count = var.create ? 1 : 0
+  count = var.create && var.create_alert_manager ? 1 : 0
 
   workspace_id = local.workspace_id
   definition   = var.alert_manager_definition

variables.tf

@@ -48,6 +48,12 @@ variable "kms_key_arn" {
 # Alert Manager Definition
 ################################################################################
 
+variable "create_alert_manager" {
+  description = "Controls whether an Alert Manager definition is created along with the AMP workspace"
+  type        = bool
+  default     = true
+}
+
 variable "alert_manager_definition" {
   description = "The alert manager definition that you want to be applied. See more in the [AWS Docs](https://docs.aws.amazon.com/prometheus/latest/userguide/AMP-alert-manager.html)"
   type        = string