AWS Secrets Manager Construct Library
import * as secretsmanager from '@aws-cdk/aws-secretsmanager';
Create a new Secret in a Stack
In order to have SecretsManager generate a new secret value automatically,
you can get started with the following:
example of creating a secret
The Secret
construct does not allow specifying the SecretString
property
of the AWS::SecretsManager::Secret
resource (as this will almost always
lead to the secret being surfaced in plain text and possibly committed to
your source control).
If you need to use a pre-existing secret, the recommended way is to manually
provision the secret in AWS SecretsManager and use the Secret.fromSecretArn
or Secret.fromSecretAttributes
method to make it available in your CDK Application:
const secret = secretsmanager.Secret.fromSecretAttributes(scope, 'ImportedSecret', {
secretArn: 'arn:aws:secretsmanager:<region>:<account-id-number>:secret:<secret-name>-<random-6-characters>',
encryptionKey,
});
SecretsManager secret values can only be used in select set of properties. For the
list of properties, see the CloudFormation Dynamic References documentation.
A secret can set RemovalPolicy
. If it set to RETAIN
, that removing a secret will fail.
Grant permission to use the secret to a role
You must grant permission to a resource for that resource to be allowed to
use a secret. This can be achieved with the Secret.grantRead
and/or Secret.grantUpdate
method, depending on your need:
const role = new iam.Role(stack, 'SomeRole', { assumedBy: new iam.AccountRootPrincipal() });
const secret = new secretsmanager.Secret(stack, 'Secret');
secret.grantRead(role);
secret.grantWrite(role);
If, as in the following example, your secret was created with a KMS key:
const key = new kms.Key(stack, 'KMS');
const secret = new secretsmanager.Secret(stack, 'Secret', { encryptionKey: key });
secret.grantRead(role);
secret.grantWrite(role);
then Secret.grantRead
and Secret.grantWrite
will also grant the role the
relevant encrypt and decrypt permissions to the KMS key through the
SecretsManager service principal.
The principal is automatically added to Secret resource policy and KMS Key policy for cross account access:
const otherAccount = new iam.AccountPrincipal('1234');
const key = new kms.Key(stack, 'KMS');
const secret = new secretsmanager.Secret(stack, 'Secret', { encryptionKey: key });
secret.grantRead(otherAccount);
Rotating a Secret
Using a Custom Lambda Function
A rotation schedule can be added to a Secret using a custom Lambda function:
const fn = new lambda.Function(...);
const secret = new secretsmanager.Secret(this, 'Secret');
secret.addRotationSchedule('RotationSchedule', {
rotationLambda: fn,
automaticallyAfter: Duration.days(15)
});
Note: The required permissions for Lambda to call SecretsManager and the other way round are automatically granted based on AWS Documentation as long as the Lambda is not imported.
See Overview of the Lambda Rotation Function on how to implement a Lambda Rotation Function.
Using a Hosted Lambda Function
Use the hostedRotation
prop to rotate a secret with a hosted Lambda function:
const secret = new secretsmanager.Secret(this, 'Secret');
secret.addRotationSchedule('RotationSchedule', {
hostedRotation: secretsmanager.HostedRotation.mysqlSingleUser(),
});
Hosted rotation is available for secrets representing credentials for MySQL, PostgreSQL, Oracle,
MariaDB, SQLServer, Redshift and MongoDB (both for the single and multi user schemes).
When deployed in a VPC, the hosted rotation implements ec2.IConnectable
:
const myHostedRotation = secretsmanager.HostedRotation.mysqlSingleUser({ vpc: myVpc });
secret.addRotationSchedule('RotationSchedule', { hostedRotation: myHostedRotation });
dbConnections.allowDefaultPortFrom(hostedRotation);
See also Automating secret creation in AWS CloudFormation.
Rotating database credentials
Define a SecretRotation
to rotate database credentials:
new secretsmanager.SecretRotation(this, 'SecretRotation', {
application: secretsmanager.SecretRotationApplication.MYSQL_ROTATION_SINGLE_USER,
secret: mySecret,
target: myDatabase,
vpc: myVpc,
excludeCharacters: ' %+:;{}',
});
The secret must be a JSON string with the following format:
{
"engine": "<required: database engine>",
"host": "<required: instance host name>",
"username": "<required: username>",
"password": "<required: password>",
"dbname": "<optional: database name>",
"port": "<optional: if not specified, default port will be used>",
"masterarn": "<required for multi user rotation: the arn of the master secret which will be used to create users/change passwords>"
}
For the multi user scheme, a masterSecret
must be specified:
new secretsmanager.SecretRotation(stack, 'SecretRotation', {
application: secretsmanager.SecretRotationApplication.MYSQL_ROTATION_MULTI_USER,
secret: myUserSecret,
masterSecret: myMasterSecret,
target: myDatabase,
vpc: myVpc,
});
See also aws-rds where
credentials generation and rotation is integrated.
Importing Secrets
Existing secrets can be imported by ARN, name, and other attributes (including the KMS key used to encrypt the secret).
Secrets imported by name should use the short-form of the name (without the SecretsManager-provided suffx);
the secret name must exist in the same account and region as the stack.
Importing by name makes it easier to reference secrets created in different regions, each with their own suffix and ARN.
import * as kms from '@aws-cdk/aws-kms';
const secretCompleteArn = 'arn:aws:secretsmanager:eu-west-1:111111111111:secret:MySecret-f3gDy9';
const secretPartialArn = 'arn:aws:secretsmanager:eu-west-1:111111111111:secret:MySecret';
const encryptionKey = kms.Key.fromKeyArn(stack, 'MyEncKey', 'arn:aws:kms:eu-west-1:111111111111:key/21c4b39b-fde2-4273-9ac0-d9bb5c0d0030');
const mySecretFromCompleteArn = secretsmanager.Secret.fromSecretCompleteArn(stack, 'SecretFromCompleteArn', secretCompleteArn);
const mySecretFromPartialArn = secretsmanager.Secret.fromSecretPartialArn(stack, 'SecretFromPartialArn', secretPartialArn);
const mySecretFromName = secretsmanager.Secret.fromSecretNameV2(stack, 'SecretFromName', 'MySecret')
const mySecretFromAttrs = secretsmanager.Secret.fromSecretAttributes(stack, 'SecretFromAttributes', {
secretCompleteArn,
encryptionKey,
});
Replicating secrets
Secrets can be replicated to multiple regions by specifying replicaRegions
:
new secretsmanager.Secret(this, 'Secret', {
replicaRegions: [
{
region: 'eu-west-1',
},
{
region: 'eu-central-1',
encryptionKey: myKey,
}
]
});
Alternatively, use addReplicaRegion()
:
const secret = new secretsmanager.Secret(this, 'Secret');
secret.addReplicaRegion('eu-west-1');