Namespace Amazon.CDK.AWS.Lambda

AWS Lambda Construct Library

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This construct library allows you to define AWS Lambda Functions.

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda;
using Path;

Function fn = new Function(this, "MyFunction", new FunctionProps {
    Runtime = Runtime.NODEJS_10_X,
    Handler = "index.handler",
    Code = Code.FromAsset(Join(__dirname, "lambda-handler"))
});

Handler Code

The lambda.Code class includes static convenience methods for various types of runtime code.

The following example shows how to define a Python function and deploy the code from the local directory my-lambda-handler to it:

// Example automatically generated. See https://github.com/aws/jsii/issues/826
new Function(this, "MyLambda", new FunctionProps {
    Code = Code.FromAsset(Join(__dirname, "my-lambda-handler")),
    Handler = "index.main",
    Runtime = Runtime.PYTHON_3_6
});

When deploying a stack that contains this code, the directory will be zip archived and then uploaded to an S3 bucket, then the exact location of the S3 objects will be passed when the stack is deployed.

During synthesis, the CDK expects to find a directory on disk at the asset directory specified. Note that we are referencing the asset directory relatively to our CDK project directory. This is especially important when we want to share this construct through a library. Different programming languages will have different techniques for bundling resources into libraries.

Layers

The lambda.LayerVersion class can be used to define Lambda layers and manage granting permissions to other AWS accounts or organizations.

// Example automatically generated. See https://github.com/aws/jsii/issues/826
LayerVersion layer = new LayerVersion(stack, "MyLayer", new LayerVersionProps {
    Code = Code.FromAsset(Join(__dirname, "layer-code")),
    CompatibleRuntimes = new [] { Runtime.NODEJS_10_X },
    License = "Apache-2.0",
    Description = "A layer to test the L2 construct"
});

// To grant usage by other AWS accounts
layer.AddPermission("remote-account-grant", new LayerVersionPermission { AccountId = awsAccountId });

// To grant usage to all accounts in some AWS Ogranization
// layer.grantUsage({ accountId: '*', organizationId });

// To grant usage to all accounts in some AWS Ogranization
// layer.grantUsage({ accountId: '*', organizationId });
new Function(stack, "MyLayeredLambda", new FunctionProps {
    Code = new InlineCode("foo"),
    Handler = "index.handler",
    Runtime = Runtime.NODEJS_10_X,
    Layers = new [] { layer }
});

Event Rule Target

You can use an AWS Lambda function as a target for an Amazon CloudWatch event rule:

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Events.Targets;
rule.AddTarget(new LambdaFunction(myFunction));

Event Sources

AWS Lambda supports a variety of event sources.

In most cases, it is possible to trigger a function as a result of an event by using one of the add<Event>Notification methods on the source construct. For example, the s3.Bucket construct has an onEvent method which can be used to trigger a Lambda when an event, such as PutObject occurs on an S3 bucket.

An alternative way to add event sources to a function is to use function.addEventSource(source). This method accepts an IEventSource object. The module @aws-cdk/aws-lambda-event-sources includes classes for the various event sources supported by AWS Lambda.

For example, the following code adds an SQS queue as an event source for a function:

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda.EventSources;
fn.AddEventSource(new SqsEventSource(queue));

The following code adds an S3 bucket notification as an event source:

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda.EventSources;
fn.AddEventSource(new S3EventSource(bucket, new S3EventSourceProps {
    Events = new [] { s3.EventType.OBJECT_CREATED, s3.EventType.OBJECT_DELETED },
    Filters = new [] { new NotificationKeyFilter { Prefix = "subdir/" } }
}));

See the documentation for the @aws-cdk/aws-lambda-event-sources module for more details.

Lambda with DLQ

A dead-letter queue can be automatically created for a Lambda function by setting the deadLetterQueueEnabled: true configuration.

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda;

Function fn = new Function(this, "MyFunction", new FunctionProps {
    Runtime = Runtime.NODEJS_10_X,
    Handler = "index.handler",
    Code = Code.FromInline("exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); }"),
    DeadLetterQueueEnabled = true
});

It is also possible to provide a dead-letter queue instead of getting a new queue created:

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda;
using Amazon.CDK.AWS.SQS;

Queue dlq = new Queue(this, "DLQ");
Function fn = new Function(this, "MyFunction", new FunctionProps {
    Runtime = Runtime.NODEJS_10_X,
    Handler = "index.handler",
    Code = Code.FromInline("exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); }"),
    DeadLetterQueue = dlq
});

See the AWS documentation to learn more about AWS Lambdas and DLQs.

Lambda with X-Ray Tracing

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda;

Function fn = new Function(this, "MyFunction", new FunctionProps {
    Runtime = Runtime.NODEJS_10_X,
    Handler = "index.handler",
    Code = Code.FromInline("exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); }"),
    Tracing = Tracing.ACTIVE
});

See the AWS documentation to learn more about AWS Lambda's X-Ray support.

Lambda with Reserved Concurrent Executions

// Example automatically generated without compilation. See https://github.com/aws/jsii/issues/826
using Amazon.CDK.AWS.Lambda;

Function fn = new Function(this, "MyFunction", new FunctionProps {
    Runtime = Runtime.NODEJS_10_X,
    Handler = "index.handler",
    Code = Code.FromInline("exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); }"),
    ReservedConcurrentExecutions = 100
});

See the AWS documentation managing concurrency.

Log Group

Lambda functions automatically create a log group with the name /aws/lambda/<function-name> upon first execution with log data set to never expire.

The logRetention property can be used to set a different expiration period.

It is possible to obtain the function's log group as a logs.ILogGroup by calling the logGroup property of the Function construct.

Note that, if either logRetention is set or logGroup property is called, a CloudFormation custom resource is added to the stack that pre-creates the log group as part of the stack deployment, if it already doesn't exist, and sets the correct log retention period (never expire, by default).

Further note that, if the log group already exists and the logRetention is not set, the custom resource will reset the log retention to never expire even if it was configured with a different value.

Singleton Function

The SingletonFunction construct is a way to guarantee that a lambda function will be guaranteed to be part of the stack, once and only once, irrespective of how many times the construct is declared to be part of the stack. This is guaranteed as long as the uuid property and the optional lambdaPurpose property stay the same whenever they're declared into the stack.

A typical use case of this function is when a higher level construct needs to declare a Lambda function as part of it but needs to guarantee that the function is declared once. However, a user of this higher level construct can declare it any number of times and with different properties. Using SingletonFunction here with a fixed uuid will guarantee this.

For example, the LogRetention construct requires only one single lambda function for all different log groups whose retention it seeks to manage.

Language-specific APIs

Language-specific higher level constructs are provided in separate modules:

Classes

Alias	A new alias to a particular version of a Lambda function.
AliasAttributes
AliasProps	Properties for a new Lambda alias.
AssetCode	Lambda code from a local directory.
CfnAlias	A CloudFormation AWS::Lambda::Alias.
CfnAlias.AliasRoutingConfigurationProperty
CfnAlias.ProvisionedConcurrencyConfigurationProperty
CfnAlias.VersionWeightProperty
CfnAliasProps	Properties for defining a AWS::Lambda::Alias.
CfnEventInvokeConfig	A CloudFormation AWS::Lambda::EventInvokeConfig.
CfnEventInvokeConfig.DestinationConfigProperty
CfnEventInvokeConfig.OnFailureProperty
CfnEventInvokeConfig.OnSuccessProperty
CfnEventInvokeConfigProps	Properties for defining a AWS::Lambda::EventInvokeConfig.
CfnEventSourceMapping	A CloudFormation AWS::Lambda::EventSourceMapping.
CfnEventSourceMapping.DestinationConfigProperty
CfnEventSourceMapping.OnFailureProperty
CfnEventSourceMappingProps	Properties for defining a AWS::Lambda::EventSourceMapping.
CfnFunction	A CloudFormation AWS::Lambda::Function.
CfnFunction.CodeProperty
CfnFunction.DeadLetterConfigProperty
CfnFunction.EnvironmentProperty
CfnFunction.TracingConfigProperty
CfnFunction.VpcConfigProperty
CfnFunctionProps	Properties for defining a AWS::Lambda::Function.
CfnLayerVersion	A CloudFormation AWS::Lambda::LayerVersion.
CfnLayerVersion.ContentProperty
CfnLayerVersionPermission	A CloudFormation AWS::Lambda::LayerVersionPermission.
CfnLayerVersionPermissionProps	Properties for defining a AWS::Lambda::LayerVersionPermission.
CfnLayerVersionProps	Properties for defining a AWS::Lambda::LayerVersion.
CfnParametersCode	Lambda code defined using 2 CloudFormation parameters.
CfnParametersCodeProps	Construction properties for {@link CfnParametersCode}.
CfnPermission	A CloudFormation AWS::Lambda::Permission.
CfnPermissionProps	Properties for defining a AWS::Lambda::Permission.
CfnVersion	A CloudFormation AWS::Lambda::Version.
CfnVersion.ProvisionedConcurrencyConfigurationProperty
CfnVersionProps	Properties for defining a AWS::Lambda::Version.
Code
CodeConfig
DestinationConfig	A destination configuration.
DestinationOptions	Options when binding a destination to a function.
DestinationType	The type of destination.
DlqDestinationConfig	A destination configuration.
EventInvokeConfig	Configure options for asynchronous invocation on a version or an alias.
EventInvokeConfigOptions	Options to add an EventInvokeConfig to a function.
EventInvokeConfigProps	Properties for an EventInvokeConfig.
EventSourceMapping	Defines a Lambda EventSourceMapping resource.
EventSourceMappingOptions
EventSourceMappingProps	Properties for declaring a new event source mapping.
Function	Deploys a file from from inside the construct library as a function.
FunctionAttributes	Represents a Lambda function defined outside of this stack.
FunctionBase
FunctionOptions	Non runtime options.
FunctionProps
InlineCode	Lambda code from an inline string (limited to 4KiB).
LambdaRuntimeProps
LayerVersion	Defines a new Lambda Layer version.
LayerVersionAttributes	Properties necessary to import a LayerVersion.
LayerVersionPermission	Identification of an account (or organization) that is allowed to access a Lambda Layer Version.
LayerVersionProps
LogRetention	Creates a custom resource to control the retention policy of a CloudWatch Logs log group.
LogRetentionProps	Construction properties for a LogRetention.
Permission	Represents a permission statement that can be added to a Lambda's resource policy via the addToResourcePolicy method.
QualifiedFunctionBase
ResourceBindOptions
Runtime	Lambda function runtime environment.
RuntimeFamily
S3Code	Lambda code from an S3 archive.
SingletonFunction	A Lambda that will only ever be added to a stack once.
SingletonFunctionProps	Properties for a newly created singleton Lambda.
StartingPosition	The position in the DynamoDB or Kinesis stream where AWS Lambda should start reading.
Tracing	X-Ray Tracing Modes (https://docs.aws.amazon.com/lambda/latest/dg/API_TracingConfig.html).
Version_	A single newly-deployed version of a Lambda function.
VersionAttributes
VersionProps	Properties for a new Lambda version.
VersionWeight	A version/weight pair for routing traffic to Lambda functions.

Interfaces

CfnAlias.IAliasRoutingConfigurationProperty
CfnAlias.IProvisionedConcurrencyConfigurationProperty
CfnAlias.IVersionWeightProperty
CfnEventInvokeConfig.IDestinationConfigProperty
CfnEventInvokeConfig.IOnFailureProperty
CfnEventInvokeConfig.IOnSuccessProperty
CfnEventSourceMapping.IDestinationConfigProperty
CfnEventSourceMapping.IOnFailureProperty
CfnFunction.ICodeProperty
CfnFunction.IDeadLetterConfigProperty
CfnFunction.IEnvironmentProperty
CfnFunction.ITracingConfigProperty
CfnFunction.IVpcConfigProperty
CfnLayerVersion.IContentProperty
CfnVersion.IProvisionedConcurrencyConfigurationProperty
IAlias
IAliasAttributes
IAliasProps	Properties for a new Lambda alias.
ICfnAliasProps	Properties for defining a AWS::Lambda::Alias.
ICfnEventInvokeConfigProps	Properties for defining a AWS::Lambda::EventInvokeConfig.
ICfnEventSourceMappingProps	Properties for defining a AWS::Lambda::EventSourceMapping.
ICfnFunctionProps	Properties for defining a AWS::Lambda::Function.
ICfnLayerVersionPermissionProps	Properties for defining a AWS::Lambda::LayerVersionPermission.
ICfnLayerVersionProps	Properties for defining a AWS::Lambda::LayerVersion.
ICfnParametersCodeProps	Construction properties for {@link CfnParametersCode}.
ICfnPermissionProps	Properties for defining a AWS::Lambda::Permission.
ICfnVersionProps	Properties for defining a AWS::Lambda::Version.
ICodeConfig
IDestination	A Lambda destination.
IDestinationConfig	A destination configuration.
IDestinationOptions	Options when binding a destination to a function.
IDlqDestinationConfig	A destination configuration.
IEventInvokeConfigOptions	Options to add an EventInvokeConfig to a function.
IEventInvokeConfigProps	Properties for an EventInvokeConfig.
IEventSource	An abstract class which represents an AWS Lambda event source.
IEventSourceDlq	A DLQ for an event source.
IEventSourceMapping	Represents an event source mapping for a lambda function.
IEventSourceMappingOptions
IEventSourceMappingProps	Properties for declaring a new event source mapping.
IFunction
IFunctionAttributes	Represents a Lambda function defined outside of this stack.
IFunctionOptions	Non runtime options.
IFunctionProps
ILambdaRuntimeProps
ILayerVersion
ILayerVersionAttributes	Properties necessary to import a LayerVersion.
ILayerVersionPermission	Identification of an account (or organization) that is allowed to access a Lambda Layer Version.
ILayerVersionProps
ILogRetentionProps	Construction properties for a LogRetention.
IPermission	Represents a permission statement that can be added to a Lambda's resource policy via the addToResourcePolicy method.
IResourceBindOptions
ISingletonFunctionProps	Properties for a newly created singleton Lambda.
IVersion
IVersionAttributes
IVersionProps	Properties for a new Lambda version.
IVersionWeight	A version/weight pair for routing traffic to Lambda functions.