AWS::Serverless::LayerVersion
Creates a Lambda LayerVersion that contains library or runtime code needed by a Lambda Function.
The AWS::Serverless::LayerVersion resource also supports the Metadata
resource attribute, so you can instruct AWS SAM to build layers included in your
application. For more information about building layers, see Building layers.
Important Note: Since the release of the UpdateReplacePolicy resource attribute in AWS CloudFormation, AWS::Lambda::LayerVersion (recommended) offers the same benefits as AWS::Serverless::LayerVersion.
When a Serverless LayerVersion is transformed, SAM also transforms the logical id of the resource so that old LayerVersions are not automatically deleted by CloudFormation when the resource is updated.
Syntax
To declare this entity in your AWS Serverless Application Model (AWS SAM) template, use the following syntax.
YAML
Type: AWS::Serverless::LayerVersion Properties: CompatibleRuntimes:
List
ContentUri:String | LayerContent
Description:String
LayerName:String
LicenseInfo:String
RetentionPolicy:String
Properties
-
CompatibleRuntimes
-
List of runtimes compatible with this LayerVersion.
Type: List
Required: No
AWS CloudFormation compatibility: This property is passed directly to the
CompatibleRuntimes
property of anAWS::Lambda::LayerVersion
resource. -
ContentUri
-
AWS S3 Uri, local file path, or LayerContent object of the layer code.
If an AWS S3 Uri or LayerContent object is provided, The AWS S3 object referenced must be a valid ZIP archive that contains the contents of an AWS Lambda layer.
If a local file path is provided, the template must go through the workflow that includes the
sam deploy
orsam package
command, in order for the content to be transformed properly.Type: String | LayerContent
Required: Yes
AWS CloudFormation compatibility: This property is similar to the
Content
property of anAWS::Lambda::LayerVersion
resource. The nested Amazon S3 properties are named differently. -
Description
-
Description of this layer.
Type: String
Required: No
AWS CloudFormation compatibility: This property is passed directly to the
Description
property of anAWS::Lambda::LayerVersion
resource. -
LayerName
-
The name or Amazon Resource Name (ARN) of the layer.
Type: String
Required: No
Default: Resource logical id
AWS CloudFormation compatibility: This property is similar to the
LayerName
property of anAWS::Lambda::LayerVersion
resource. If you don't specify a name, the logical id of the resource will be used as the name. -
LicenseInfo
-
Information about the license for this LayerVersion.
Type: String
Required: No
AWS CloudFormation compatibility: This property is passed directly to the
LicenseInfo
property of anAWS::Lambda::LayerVersion
resource. -
RetentionPolicy
-
Specifies whether old versions of your LayerVersion are retained or deleted after an update.
Valid values:
Retain
orDelete
Type: String
Required: No
AWS CloudFormation compatibility: This property is unique to AWS SAM and doesn't have an AWS CloudFormation equivalent.
Additional notes: When you specify
Retain
, AWS SAM adds a Resource attributes ofDeletionPolicy: Retain
to the transformedAWS::Lambda::LayerVersion
resource.
Return Values
Ref
When the logical ID of this resource is provided to the Ref
intrinsic function, it returns the resource ARN of the underlying Lambda LayerVersion.
For more information about using the Ref
function, see Ref
in the AWS CloudFormation User Guide.
Examples
LayerVersionExample
Example of a LayerVersion
YAML
Properties: LayerName: MyLayer Description: Layer description ContentUri: 's3://my-bucket/my-layer.zip' CompatibleRuntimes: - nodejs10.x - nodejs12.x LicenseInfo: 'Available under the MIT-0 license.' RetentionPolicy: Retain