Provides CloudWatch alarms. This module's support is currently limited to ECS services, and currently supports only the CPUUtilization and MemoryUtilization metrics.

In this minimum viable implementation, the CloudWatch alarm period, and statistic are hardcoded. Thresholds for the CPUUtilization and MemoryUtilization metrics can be specified by the caller; both values are numeric percentages.

module "alarm" {
  source = "[email protected]:techservicesillinois/terraform-aws-cloudwatch-alarm"

  name = "foo"

  subscriptions = [
      {
        protocol = "sms"
        endpoint = "+18005551212"
      },
  ]

  ecs_cluster = "foo"

  ecs_services = {
    "foo-daemon" = {
      cpu    = 90
      memory = 85
    },

    "foo-ui" = {
      cpu    = 75
      memory = 75
    }
  }
}

The following arguments are supported:

• ecs_cluster – (Required) ECS cluster containing services for which alarms are created.

• ecs_services – (Optional) Map of ECS services for which alarms are created; key is name of service and value is an object with the attributes cpu and memory. Both attributes are numeric values.

• name – (Required) Service name. This is used to form the name of alarm(s).

• subscriptions (Optional) A subscriptions block. The subscriptions block is documented below.

• tags – (Optional) Tags to be applied to resources where supported.

A subscription block consists of a list containing one or more maps, each of which must contain the following keys:

• protocol – (Required) The protocol to use. The fully-supported values for this are: sqs, sms, lambda, application.

• endpoint – (Required) The endpoint to send data to, the contents will vary with the protocol.

Note: AWS supports additional email and email-json protocols that are not supported by Terraform because the authorization process does not generate an ARN until the target email address has been validated. However, subscriptions using the email and email-json protocols can be created in the AWS console.

Additionally, http and https protocols are only partially supported by Terraform.

For further information, see the documentation on Terraform's terraform-sns-topic-subscription resource. The Amazon documentation on the Simple Notification Service (SNS) may also be helpful.

The following attributes are exported:

• alarm_arn – List consisting of ARNs of each alarm managed by the module.

• topic_arn - ARN of the SNS alarm topic for this service.