CloudWatch alerts to Slack

Configuration in this directory creates a VPC, an SNS topic that sends messages to a Slack channel with Slack webhook URL encrypted using KMS and a CloudWatch Alarm that monitors the duration of lambda execution.

KMS keys

There are 3 ways to define KMS key which should be used by Lambda function:

1. Create aws_kms_key resource and put ARN of it as kms_key_arn argument to this module
2. Use aws_kms_alias data-source to get an existing KMS key alias and put ARN of it as kms_key_arn argument to this module
3. Hard-code the ARN of KMS key

Option 1:

resource "aws_kms_key" "this" {
  description = "KMS key for notify-slack test"
}

resource "aws_kms_alias" "this" {
  name          = "alias/kms-test-key"
  target_key_id = aws_kms_key.this.id
}

// kms_key_arn = aws_kms_key.this.arn

Option 2:

data "aws_kms_alias" "this" {
 name = "alias/kms-test-key"
}

// kms_key_arn = data.aws_kms_alias.this.target_key_arn

Option 3:

// kms_key_arn = "arn:aws:kms:eu-west-1:835367859851:key/054b4846-95fe-4537-94f2-1dfd255238cf"

Usage

To run this example you need to execute:

$ terraform init
$ terraform plan
$ terraform apply

Note that in practice, encryption of the Slack webhook URL should happen differently (outside of this module).

Note that this example may create resources which can cost money. Run terraform destroy when you don't need these resources.

Requirements

Name	Version
terraform	>= 1.0
aws	>= 4.8
random	>= 2.0

Providers

Name	Version
aws	>= 4.8
random	>= 2.0

Modules

Name	Source	Version
notify_slack	../../	n/a
vpc	terraform-aws-modules/vpc/aws	n/a

Resources

Name	Type
aws_cloudwatch_metric_alarm.lambda_duration	resource
aws_kms_ciphertext.slack_url	resource
aws_kms_key.this	resource
random_pet.this	resource

Inputs

No inputs.

Outputs

Name	Description
lambda_iam_role_arn	The ARN of the IAM role used by Lambda function
lambda_iam_role_name	The name of the IAM role used by Lambda function
notify_slack_lambda_function_arn	The ARN of the Lambda function
notify_slack_lambda_function_invoke_arn	The ARN to be used for invoking Lambda function from API Gateway
notify_slack_lambda_function_last_modified	The date Lambda function was last modified
notify_slack_lambda_function_name	The name of the Lambda function
notify_slack_lambda_function_version	Latest published version of your Lambda function
sns_topic_arn	The ARN of the SNS topic from which messages will be sent to Slack