Terraform AWS Lambda module

About:

Setup of a Lambda function with CloudWatch Alarms.

The following boolean variables control which alarms will be enabled;

• create_errorRate_alarm: Alarms on errors with a default of threshold of 1 percent during a 5 minute measurement period
• create_throttleCount_alarm: Alarm on throttle count of 1 within 1 minute measurement period
• create_iteratorAge_alarm: Alarm for Stream based invocations such as Kinesis, alerts you when the time to execute is over 1 minute within a 5 minute measurement period
  • More on the iteratorAge metric here
• create_deadLetterQueue_alarm: Alarm for DLQueue messages (for async Lambda invocations or SQS queues for example), 1 message within 1 minute triggers the alarm.

This AWS Lambda module can integrate with the following:

• API Gateway: The parameter create_api_gateway_integration is set to true by default, supply the api_gateway_rest_api_id
• SNS Topic: The parameter create_sns_topic_subscription is set to false by default.
• SQS: The parameter create_sqs_integration is set to false by default. This can create an event source mapping to an SQS queue.

How to use:

Use the code below in combination with the tf-iam module (module.iam.role_arn) to set the correct IAM policies.

module "lambda" {
  source = "github.com/rpstreef/tf-lambda?ref=v1.0"

  namespace         = var.namespace
  region            = var.region
  resource_tag_name = var.resource_tag_name

  lambda_function_name = local.lambda_function_name
  lambda_role_arn      = module.iam.role_arn
  lambda_layer_arn     = var.lambda_layer_arn

  lambda_memory_size = var.lambda_memory_size
  lambda_timeout     = var.lambda_timeout

  lambda_environment_variables = {
    NAMESPACE = var.namespace
    REGION    = var.region

    COGNITO_USER_POOL_CLIENT_ID = var.cognito_user_pool_client_id
    COGNITO_USER_POOL_ID        = var.cognito_user_pool_id

    DEBUG_SAMPLE_RATE = var.debug_sample_rate
  }

  create_deadLetterQueue_alarm = false
  create_iteratorAge_alarm     = false

  api_gateway_rest_api_id = var.api_gateway_rest_api_id
}

Changelog

v1.3

• Removed lambda_filename variable, use CI/CD instead to deploy Lambda code

v1.2

• Added SQS event source integration

v1.1

• Added SNS Topic subscription sub-module

v1.0

• Initial release