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AWS Lambda 0.21.18Last updated in version 0.21.15

Log group for Lambda Edge

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This module creates a Cloudwatch log group to receive Lambda Edge function logs in one single AWS Region. This module is meant to be used as a building block for the lambda-edge-multi-region-log-groups module.

Why are the resources in this module not created within the Lambda Edge Module?​

Lambda@Edge automatically creates CloudWatch Logs log streams in the AWS Regions closest to the location where the function receives traffic and is executed. For these resources to be under Terraform control, a log group must be created in every region that have Regional Edge Caches.

Unfortunately, it is not possible to use a for_each on provider blocks and there are multiple issues related to using nested providers. That means that, currently, the only way to create multi-regional modules is by code generating each block and passing down the providers. A full example of creating the providers and using this module can be found at the lambda-edge example.

Which regions have regional edge caches?​

As of 22 Aug 2022, the list of regions with edge caches are:

US East (N. Virginia) – us-east-1

US East (Ohio) – us-east-2

US West (N. California) – us-west-1

US West (Oregon) – us-west-2

Asia Pacific (Mumbai) – ap-south-1

Asia Pacific (Seoul) – ap-northeast-2

Asia Pacific (Singapore) – ap-southeast-1

Asia Pacific (Sydney) – ap-southeast-2

Asia Pacific (Tokyo) – ap-northeast-1

Europe (Frankfurt) – eu-central-1

Europe (Ireland) – eu-west-1

Europe (London) – eu-west-2

South America (São Paulo) – sa-east-1

More information:

Sample Usage​

main.tf

# ------------------------------------------------------------------------------------------------------
# DEPLOY GRUNTWORK'S LAMBDA-EDGE-LOG-GROUP MODULE
# ------------------------------------------------------------------------------------------------------

module "lambda_edge_log_group" {

  source = "git::git@github.com:gruntwork-io/terraform-aws-lambda.git//modules/lambda-edge-log-group?ref=v0.21.18"

  # ----------------------------------------------------------------------------------------------------
  # REQUIRED VARIABLES
  # ----------------------------------------------------------------------------------------------------

  # The name of the log group.
  name = <string>

  # ----------------------------------------------------------------------------------------------------
  # OPTIONAL VARIABLES
  # ----------------------------------------------------------------------------------------------------

  # The ID (ARN, alias ARN, AWS ID) of a customer managed KMS Key to use for
  # encrypting log data.
  cloudwatch_log_group_kms_key_id = null

  # The number of days to retain log events in the log group. Refer to
  # https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudwatch_log_group#retention_in_days
  # for all the valid values. When null, the log events are retained forever.
  cloudwatch_log_group_retention_in_days = null

  # The ARN of the destination to deliver matching log events to. Kinesis stream
  # or Lambda function ARN. Only applicable if
  # var.should_create_cloudwatch_log_group is true.
  cloudwatch_log_group_subscription_destination_arn = null

  # The method used to distribute log data to the destination. Only applicable
  # when var.cloudwatch_log_group_subscription_destination_arn is a kinesis
  # stream. Valid values are `Random` and `ByLogStream`.
  cloudwatch_log_group_subscription_distribution = null

  # A valid CloudWatch Logs filter pattern for subscribing to a filtered stream
  # of log events.
  cloudwatch_log_group_subscription_filter_pattern = ""

  # ARN of an IAM role that grants Amazon CloudWatch Logs permissions to deliver
  # ingested log events to the destination. Only applicable when
  # var.cloudwatch_log_group_subscription_destination_arn is a kinesis stream.
  cloudwatch_log_group_subscription_role_arn = null

  # Tags to apply on the CloudWatch Log Group, encoded as a map where the keys
  # are tag keys and values are tag values.
  cloudwatch_log_group_tags = {}

  # When true, precreate the CloudWatch Log Group to use for log aggregation
  # from the lambda function execution. This is useful if you wish to customize
  # the CloudWatch Log Group with various settings such as retention periods and
  # KMS encryption. When false, AWS Lambda will automatically create a basic log
  # group to use.
  should_create_cloudwatch_log_group = true

}


Reference​

Required​

namestringrequired

The name of the log group.

Optional​

The ID (ARN, alias ARN, AWS ID) of a customer managed KMS Key to use for encrypting log data.

null

The number of days to retain log events in the log group. Refer to https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudwatch_log_group#retention_in_days for all the valid values. When null, the log events are retained forever.

null

The ARN of the destination to deliver matching log events to. Kinesis stream or Lambda function ARN. Only applicable if should_create_cloudwatch_log_group is true.

null

The method used to distribute log data to the destination. Only applicable when cloudwatch_log_group_subscription_destination_arn is a kinesis stream. Valid values are Random and ByLogStream.

null

A valid CloudWatch Logs filter pattern for subscribing to a filtered stream of log events.

""

ARN of an IAM role that grants Amazon CloudWatch Logs permissions to deliver ingested log events to the destination. Only applicable when cloudwatch_log_group_subscription_destination_arn is a kinesis stream.

null
cloudwatch_log_group_tagsmap(string)optional

Tags to apply on the CloudWatch Log Group, encoded as a map where the keys are tag keys and values are tag values.

{}

When true, precreate the CloudWatch Log Group to use for log aggregation from the lambda function execution. This is useful if you wish to customize the CloudWatch Log Group with various settings such as retention periods and KMS encryption. When false, AWS Lambda will automatically create a basic log group to use.

true