AWS RDS Secret Rotation

A Terraform module that creates an AWS Secrets Manager secret for RDS, with optional rotation support.

Features

• Creates secret with the correct format required by RDS.
• Supports PostgreSQL but is easy to add other engines.
• When rotation is enabled, all required infrastructure is created (lambda, security group, etc)

Secret rotation is not only a great thing to do from a security perspective, but it negates the worry about the aws_rds_cluster resource storing passwords in state.

Usage

PostgreSQL Aurora Serverless

module "root_user" {
  source = "JCapriotti/rds-secret-rotation"

  db_cluster_identifier = "my-db"
  engine                = "postgres"
  host                  = "my-db.cluster-xxxxxxxx.us-east-1.rds.amazonaws.com"
  name_prefix           = "my-db-"
  port                  = 5432
  username              = "root"
  password              = "SomethingSecret!"
  rotation_days         = 7

  rotation_lambda_subnet_ids = ["subnet-0123456789", "subnet-abcdef0123"]
  rotation_lambda_vpc_id     = "vpc-0123456789"
  db_security_group_id       = aws_security_group.rds.id
}

Inputs

Name	Description	Type	Default	Required
db_cluster_identifier	The DB cluster identifier	string		yes
db_security_group_id	The security group ID for the database. Required for secret rotation.	string	null	no
engine	The database engine type	string		yes
host	The host name of the database instance	string		yes
master_secret_arn	The superuser credentials used to update another secret in the multiuser rotation strategy. Required when using multipleuser rotation strategy.	string	null	no
name_prefix	The prefix for names of created resources.	string		yes
password	The password for the user.	string		yes
port	The port number of the database instance.	number		yes
rotation_days	The number of days between rotations. When set to null (the default) rotation is not configured.	number	null	no
rotation_lambda_env_variables	Optional environment variables for the rotation lambda; useful for integration with for certain layer providers.	map(string)	{}	no
rotation_lambda_handler	An optional lambda handler name; useful integration with for certain layer providers.	string	null	no
rotation_lambda_layers	Optional layers for the rotation lambda.	list(string)	null	no
rotation_lambda_policy_jsons	Additional policies to add to the rotation lambda; useful for integration with layer providers.	list(string)	[]	no
rotation_lambda_subnet_ids	The VPC subnets that the rotation lambda runs in. Required for secret rotation.	list(string)	[]	no
rotation_lambda_vpc_id	The VPC that the secret rotation lambda runs in. Required for secret rotation.	string	null	no
rotation_strategy	Specifies how the secret is rotated, either by updating credentials for the user itself (single) or by using a superuser's credentials to change another user's credentials (multiuser).	string	single	no
secret_recovery_window_days	The number of days that Secrets Manager waits before deleting a secret.	number	0	no
tags	Tags to use for created resources.	map(string)	{}	no
username	The username.	string		yes
recreate_missing_package	Whether to recreate missing Lambda package if it is missing locally or not.	bool	true	no

Outputs

Name	Description
default_rotation_lambda_handler	The default lambda handler for the built-in function. Useful for when integrating with a layer.
rotation_lambda_role_name	The name of the IAM role created for the rotation lambda.
rotation_lambda_runtime	The runtime of the rotation lambda.
rotation_lambda_security_group_id	The security group created for the rotation lambda.
secret_arn	The ARN of the secret that was created.
secret_name	The name of the secret that was created.