Key

class aws_cdk.aws_kms.Key(scope, id, *, admins=None, alias=None, description=None, enabled=None, enable_key_rotation=None, key_spec=None, key_usage=None, multi_region=None, pending_window=None, policy=None, removal_policy=None, rotation_period=None)

Bases: Resource

Defines a KMS key.

Resource:: AWS::KMS::Key
ExampleMetadata:: infused

Example:

import aws_cdk.aws_kms as kms


my_kms_key = kms.Key(self, "myKMSKey")
my_bucket = s3.Bucket(self, "mySSEKMSEncryptedBucket",
    encryption=s3.BucketEncryption.KMS,
    encryption_key=my_kms_key,
    object_ownership=s3.ObjectOwnership.BUCKET_OWNER_ENFORCED
)
cloudfront.Distribution(self, "myDist",
    default_behavior=cloudfront.BehaviorOptions(
        origin=origins.S3BucketOrigin.with_origin_access_control(my_bucket)
    )
)

Parameters:

scope (Construct) –
id (str) –
admins (Optional[Sequence[IPrincipal]]) – A list of principals to add as key administrators to the key policy. Key administrators have permissions to manage the key (e.g., change permissions, revoke), but do not have permissions to use the key in cryptographic operations (e.g., encrypt, decrypt). These principals will be added to the default key policy (if none specified), or to the specified policy (if provided). Default: []
alias (Optional[str]) – Initial alias to add to the key. More aliases can be added later by calling addAlias. Default: - No alias is added for the key.
description (Optional[str]) – A description of the key. Use a description that helps your users decide whether the key is appropriate for a particular task. Default: - No description.
enabled (Optional[bool]) – Indicates whether the key is available for use. Default: - Key is enabled.
enable_key_rotation (Optional[bool]) – Indicates whether AWS KMS rotates the key. Default: false
key_spec (Optional[KeySpec]) – The cryptographic configuration of the key. The valid value depends on usage of the key. IMPORTANT: If you change this property of an existing key, the existing key is scheduled for deletion and a new key is created with the specified value. Default: KeySpec.SYMMETRIC_DEFAULT
key_usage (Optional[KeyUsage]) – The cryptographic operations for which the key can be used. IMPORTANT: If you change this property of an existing key, the existing key is scheduled for deletion and a new key is created with the specified value. Default: KeyUsage.ENCRYPT_DECRYPT
multi_region (Optional[bool]) – Creates a multi-Region primary key that you can replicate in other AWS Regions. You can’t change the multiRegion value after the KMS key is created. IMPORTANT: If you change the value of the multiRegion property on an existing KMS key, the update request fails, regardless of the value of the UpdateReplacePolicy attribute. This prevents you from accidentally deleting a KMS key by changing an immutable property value. Default: false
pending_window (Optional[Duration]) – Specifies the number of days in the waiting period before AWS KMS deletes a CMK that has been removed from a CloudFormation stack. When you remove a customer master key (CMK) from a CloudFormation stack, AWS KMS schedules the CMK for deletion and starts the mandatory waiting period. The PendingWindowInDays property determines the length of waiting period. During the waiting period, the key state of CMK is Pending Deletion, which prevents the CMK from being used in cryptographic operations. When the waiting period expires, AWS KMS permanently deletes the CMK. Enter a value between 7 and 30 days. Default: - 30 days
policy (Optional[PolicyDocument]) – Custom policy document to attach to the KMS key. NOTE - If the @aws-cdk/aws-kms:defaultKeyPolicies feature flag is set (the default for new projects), this policy will override the default key policy and become the only key policy for the key. If the feature flag is not set, this policy will be appended to the default key policy. Default: - A policy document with permissions for the account root to administer the key will be created.
removal_policy (Optional[RemovalPolicy]) – Whether the encryption key should be retained when it is removed from the Stack. This is useful when one wants to retain access to data that was encrypted with a key that is being retired. Default: RemovalPolicy.Retain
rotation_period (Optional[Duration]) – The period between each automatic rotation. Default: - set by CFN to 365 days.

Methods

add_alias(alias_name)

Defines a new alias for the key.

Parameters:

alias_name (str) –

Return type:

Alias

add_to_resource_policy(statement, allow_no_op=None)

Adds a statement to the KMS key resource policy.

Parameters:

statement (PolicyStatement) – The policy statement to add.
allow_no_op (Optional[bool]) – If this is set to false and there is no policy defined (i.e. external key), the operation will fail. Otherwise, it will no-op.

Return type:

AddToResourcePolicyResult

apply_removal_policy(policy)

Apply the given removal policy to this resource.

The Removal Policy controls what happens to this resource when it stops being managed by CloudFormation, either because you’ve removed it from the CDK application or because you’ve made a change that requires the resource to be replaced.

The resource can be deleted (RemovalPolicy.DESTROY), or left in your AWS account for data recovery and cleanup later (RemovalPolicy.RETAIN).

Parameters:

policy (RemovalPolicy) –

Return type:

None

grant(grantee, *actions)

Grant the indicated permissions on this key to the given principal.

This modifies both the principal’s policy as well as the resource policy, since the default CloudFormation setup for KMS keys is that the policy must not be empty and so default grants won’t work.

Parameters:

grantee (IGrantable) –
actions (str) –

Return type:

Grant

grant_admin(grantee)

Grant admins permissions using this key to the given principal.

Key administrators have permissions to manage the key (e.g., change permissions, revoke), but do not have permissions to use the key in cryptographic operations (e.g., encrypt, decrypt).

Parameters:

grantee (IGrantable) –

Return type:

Grant

grant_decrypt(grantee)

Grant decryption permissions using this key to the given principal.

Parameters:

grantee (IGrantable) –

Return type:

Grant

grant_encrypt(grantee)

Grant encryption permissions using this key to the given principal.

Parameters:

grantee (IGrantable) –

Return type:

Grant

grant_encrypt_decrypt(grantee)

Grant encryption and decryption permissions using this key to the given principal.

Parameters:

grantee (IGrantable) –

Return type:

Grant

grant_generate_mac(grantee)

Grant permissions to generating MACs to the given principal.

Parameters:

grantee (IGrantable) –

Return type:

Grant

grant_verify_mac(grantee)

Grant permissions to verifying MACs to the given principal.

Parameters:

grantee (IGrantable) –

Return type:

Grant

to_string()

Returns a string representation of this construct.

Return type:: str

Attributes

DEFAULT_DUMMY_KEY_ID = '1234abcd-12ab-34cd-56ef-1234567890ab'

env

The environment this resource belongs to.

For resources that are created and managed by the CDK (generally, those created by creating new class instances like Role, Bucket, etc.), this is always the same as the environment of the stack they belong to; however, for imported resources (those obtained from static methods like fromRoleArn, fromBucketName, etc.), that might be different than the stack they were imported into.

key_arn: The ARN of the key.

key_id

1234abcd-12ab-34cd-56ef-1234567890ab).

Type:: The ID of the key (the part that looks something like

node: The tree node.

stack: The stack in which this resource is defined.

Static Methods

classmethod from_cfn_key(cfn_key)

Create a mutable IKey based on a low-level CfnKey.

This is most useful when combined with the cloudformation-include module. This method is different than fromKeyArn() because the IKey returned from this method is mutable; meaning, calling any mutating methods on it, like IKey.addToResourcePolicy(), will actually be reflected in the resulting template, as opposed to the object returned from fromKeyArn(), on which calling those methods would have no effect.

Parameters:

cfn_key (CfnKey) –

Return type:

IKey

classmethod from_key_arn(scope, id, key_arn)

Import an externally defined KMS Key using its ARN.

Parameters:

scope (Construct) – the construct that will “own” the imported key.
id (str) – the id of the imported key in the construct tree.
key_arn (str) – the ARN of an existing KMS key.

Return type:

IKey

classmethod from_lookup(scope, id, *, alias_name, return_dummy_key_on_missing=None)

Import an existing Key by querying the AWS environment this stack is deployed to.

This function only needs to be used to use Keys not defined in your CDK application. If you are looking to share a Key between stacks, you can pass the Key object between stacks and use it as normal. In addition, it’s not necessary to use this method if an interface accepts an IKey. In this case, Alias.fromAliasName() can be used which returns an alias that extends IKey.

Calling this method will lead to a lookup when the CDK CLI is executed. You can therefore not use any values that will only be available at CloudFormation execution time (i.e., Tokens).

If you set returnDummyKeyOnMissing to true in options and the key was not found, this method will return a dummy key with a key id ‘1234abcd-12ab-34cd-56ef-1234567890ab’. The value of the dummy key id can also be referenced using the Key.DEFAULT_DUMMY_KEY_ID variable, and you can check if the key is a dummy key by using the Key.isLookupDummy() method.

The Key information will be cached in cdk.context.json and the same Key will be used on future runs. To refresh the lookup, you will have to evict the value from the cache using the cdk context command. See https://docs.aws.amazon.com/cdk/latest/guide/context.html for more information.

Parameters:

scope (Construct) –
id (str) –
alias_name (str) – The alias name of the Key. Must be in the format alias/<AliasName>.
return_dummy_key_on_missing (Optional[bool]) – Whether to return a dummy key if the key was not found. If it is set to true and the key was not found, a dummy key with a key id ‘1234abcd-12ab-34cd-56ef-1234567890ab’ will be returned. The value of the dummy key id can also be referenced using the Key.DEFAULT_DUMMY_KEY_ID variable, and you can check if the key is a dummy key by using the Key.isLookupDummy() method. Default: false

Return type:

IKey

classmethod is_construct(x)

Checks if x is a construct.

Use this method instead of instanceof to properly detect Construct instances, even when the construct library is symlinked.

Explanation: in JavaScript, multiple copies of the constructs library on disk are seen as independent, completely different libraries. As a consequence, the class Construct in each copy of the constructs library is seen as a different class, and an instance of one class will not test as instanceof the other class. npm install will not create installations like this, but users may manually symlink construct libraries together or use a monorepo tool: in those cases, multiple copies of the constructs library can be accidentally installed, and instanceof will behave unpredictably. It is safest to avoid using instanceof, and using this type-testing method instead.

Parameters:: x (Any) – Any object.
Return type:: bool
Returns:: true if x is an object created from a class which extends Construct.

classmethod is_lookup_dummy(key)

Checks if the key returned by the Key.fromLookup() method is a dummy key, i.e., a key that was not found.

This method can only be used if the returnDummyKeyOnMissing option is set to true in the options for the Key.fromLookup() method.

Parameters:

key (IKey) –

Return type:

bool

classmethod is_owned_resource(construct)

Returns true if the construct was created by CDK, and false otherwise.

Parameters:

construct (IConstruct) –

Return type:

bool

classmethod is_resource(construct)

Check whether the given construct is a Resource.

Parameters:

construct (IConstruct) –

Return type:

bool