cdk-lambda-subminute

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| npm (JS/TS) | PyPI (Python) | Maven (Java) | Go | NuGet |
| --- | --- | --- | --- | --- |
| Link | Link | Link | Link | Link |

This construct creates a state machine that can invoke a Lambda function per time unit which can be less than one minute, such as invoking every 10 seconds. You only need to craft a Lambda function and then assign it as an argument into the construct. An example is included.

Serverless Architecture

Introduction

This construct library is reffered to thie AWS Architecture blog post, A serverless solution for invoking AWS Lambda at a sub-minute frequency, written by Emanuele Menga. I made it as a constrcut library where you only need to care about a target Lambda function, how frequent and how long you want to execute.

Example

Typescript

You could also refer to here.
``

bash
$ cdk --init language typescript
$ yarn add cdk-lambda-subminute

typescript
class TypescriptStack extends cdk.Stack {
  constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
    super(scope, id, props);
    const targetLabmda = new Function(this, 'targetFunction', {
      code: Code.fromInline('exports.handler = function(event, ctx, cb) { return cb(null, "hi"); })'), // It's just a simple function for demonstration purpose only.
      functionName: 'testTargetFunction',
      runtime: Runtime.NODEJS_18_X,
      handler: 'index.handler',
    });
    const cronJobExample = 'cron(50/1 15-17 ?  SUN-SAT )';
    const subminuteMaster = new LambdaSubminute(this, 'LambdaSubminute', { targetFunction: targetLabmda, cronjobExpression: cronJobExample });
    new cdk.CfnOutput(this, 'OStateMachineArn', { value: subminuteMaster.stateMachineArn });
    new cdk.CfnOutput(this, 'OIteratorFunctionArn', { value: subminuteMaster.iteratorFunction.functionArn });
  }
}

const app = new cdk.App(); new TypescriptStack(app, 'TypescriptStack', { });`

`Python`


You could also refer to here.

bash
upgrading related Python packages

$ python -m ensurepip --upgrade
$ python -m pip install --upgrade pip
$ python -m pip install --upgrade virtualenv
initialize a CDK Python project

$ cdk init --language python
make packages installed locally instead of globally

$ source .venv/bin/activate
$ cat < requirements.txt
aws-cdk.core
aws-cdk.aws-lambda
cdk-lambda-subminute
EOL
$ python -m pip install -r requirements.txt

python
from aws_cdk import core as cdk
from aws_cdk.aws_lambda import Code, Function, Runtime
from cdk_lambda_subminute import LambdaSubminute
class PythonStack(cdk.Stack):
    def __init__(self, scope: cdk.Construct, construct_id: str, **kwargs) -> None:
        super().__init__(scope, construct_id, **kwargs)
        target_lambda = Function(
            self, "targetFunction",
            code=Code.from_inline(
                "exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); })"),
            function_name="testTargetFunction",
            runtime=Runtime.NODEJS_18_X,
            handler="index.handler"
        )
        cron_job_example = "cron(10/1 4-5 ?  SUN-SAT )"
        subminute_master = LambdaSubminute(
            self, "LambdaSubminute",
            target_function=target_lambda,
            cronjob_expression=cron_job_example,
            frequency=7,
            interval_time=8)

cdk.CfnOutput(self, "OStateMachineArn", value=subminute_master.state_machine_arn) cdk.CfnOutput(self, "OIteratorFunctionArn", value=subminute_master.iterator_function.function_arn)``bash $ deactivate`

`Java`


You could also refer to here.

bash
$ cdk init --language java
$ mvn package

xml
.
.

      UTF-8
      2.149.0
      2.0.442
      5.7.1

 .
 .
 
     
      
            software.amazon.awscdk
            core
            ${cdk.version}
      
      
            software.amazon.awscdk
            lambda
            ${cdk.version}
      
      
            io.github.hsiehshujeng
            cdk-lambda-subminute
            ${constrcut.verion}
      
     .
     .
     .

java
package com.myorg;
import software.amazon.awscdk.core.CfnOutput;
import software.amazon.awscdk.core.CfnOutputProps;
import software.amazon.awscdk.core.Construct;
import software.amazon.awscdk.core.Stack;
import software.amazon.awscdk.core.StackProps;
import software.amazon.awscdk.services.lambda.Code;
import software.amazon.awscdk.services.lambda.Function;
import software.amazon.awscdk.services.lambda.FunctionProps;
import software.amazon.awscdk.services.lambda.Runtime;
import io.github.hsiehshujeng.cdk.lambda.subminute.LambdaSubminute;
import io.github.hsiehshujeng.cdk.lambda.subminute.LambdaSubminuteProps;
public class JavaStack extends Stack {
    public JavaStack(final Construct scope, final String id) {
        this(scope, id, null);
    }
    public JavaStack(final Construct scope, final String id, final StackProps props) {
        super(scope, id, props);
        Function targetLambda = new Function(this, "targetFunction", 
          FunctionProps.builder()
              .code(Code.fromInline("exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); })"))
              .functionName("estTargetFunction")
              .runtime(Runtime.NODEJS_18_X)
              .handler("index.handler")
              .build());
        String cronJobExample = "cron(50/1 4-5 ?  SUN-SAT )";
        LambdaSubminute subminuteMaster = new LambdaSubminute(this, "LambdaSubminute", LambdaSubminuteProps.builder()
              .targetFunction(targetLambda)
              .cronjobExpression(cronJobExample)
              .frequency(6)
              .intervalTime(9)
              .build());
        new CfnOutput(this, "OStateMachineArn",
                CfnOutputProps.builder()
                  .value(subminuteMaster.getStateMachineArn())
                  .build());
        new CfnOutput(this, "OIteratorFunctionArn",
                CfnOutputProps.builder()
                  .value(subminuteMaster.getIteratorFunction().getFunctionName())
                  .build());
    }
}

`C#`


You could also refer to here.

bash
$ cdk init --language csharp
$ dotnet add src/Csharp package Amazon.CDK.AWS.Lambda
$ dotnet add src/Csharp package Lambda.Subminute --version 2.0.442

cs
using Amazon.CDK;
using Amazon.CDK.AWS.Lambda;
using ScottHsieh.Cdk;

namespace Csharp { public class CsharpStack : Stack { internal CsharpStack(Construct scope, string id, IStackProps props = null) : base(scope, id, props) { var targetLambda = new Function(this, "targetFunction", new FunctionProps { Code = Code.FromInline("exports.handler = function(event, ctx, cb) { return cb(null, \"hi\"); })"), FunctionName = "testTargetFunction", Runtime = Runtime.NODEJS_18_X, Handler = "index.handler" }); string cronJobExample = "cron(50/1 6-7 ? SUN-SAT )"; var subminuteMaster = new LambdaSubminute(this, "LambdaSubminute", new LambdaSubminuteProps { TargetFunction = targetLambda, CronjobExpression = cronJobExample, Frequency = 10, IntervalTime = 6, }); new CfnOutput(this, "OStateMachineArn", new CfnOutputProps { Value = subminuteMaster.StateMachineArn }); new CfnOutput(this, "OIteratorFunctionArn", new CfnOutputProps { Value = subminuteMaster.IteratorFunction.FunctionArn }); } } }`

`GO`

bash
Initialize a new AWS CDK application in the current directory with the Go programming language

cdk init app -l go
Add this custom CDK construct to your project

go get github.com/HsiehShuJeng/cdk-lambda-subminute-go/cdklambdasubminute/v2@v2.0.442
Ensure all dependencies are properly listed in the go.mod file and remove any unused ones

go mod tidy
Upgrade all Go modules in your project to their latest minor or patch versions

go get -u ./...


Statemachine Diagram  

!image  

Known issue  

Originally, I utilized

PythonFuncion

 in the module of @aws-cdk/aws-lambda-python to build the iterator Lambda function. Every thing works fine, including test, on my local machine (MacBook Pro M1), until it comes to the CI in Github Actions, it awlays gave me the following message:

bash
cdk version: 1.105.0 (build 4813992)

Bundling did not produce any output. Check that content is written to /asset-output.
      64 |     }));
      65 |
    > 66 |     this.function = new PythonFunction(this, 'Iterator', {
         |                     ^
      67 |       functionName: 'lambda-subminute-iterator',
      68 |       description: 'A function for breaking the limit of 1 minute with the CloudWatch Rules.',
      69 |       logRetention: RetentionDays.THREE_MONTHS,

at AssetStaging.bundle (node_modules/@aws-cdk/core/lib/asset-staging.ts:484:13) at AssetStaging.stageByBundling (node_modules/@aws-cdk/core/lib/asset-staging.ts:328:10) at stageThisAsset (node_modules/@aws-cdk/core/lib/asset-staging.ts:194:35) at Cache.obtain (node_modules/@aws-cdk/core/lib/private/cache.ts:24:13) at new AssetStaging (node_modules/@aws-cdk/core/lib/asset-staging.ts:219:44) at new Asset (node_modules/@aws-cdk/aws-s3-assets/lib/asset.ts:127:21) at AssetCode.bind (node_modules/@aws-cdk/aws-lambda/lib/code.ts:277:20) at new Function (node_modules/@aws-cdk/aws-lambda/lib/function.ts:583:29) at new PythonFunction (node_modules/@aws-cdk/aws-lambda-python/lib/function.ts:106:5) at new IteratorLambda (src/cdk-lambda-subminute.ts:66:21) at new LambdaSubminute (src/cdk-lambda-subminute.ts:25:22) at Object..test (test/integ.test.ts:23:3)``
I actually have tried many different methods according to the following threads but to no avail. I'll attempt to test some thoughts or just post the issue onto the CDK Github repo.
* Asset Bundling
* Change the bundler's /asset-output local volume mount location #8589
* (aws-lambda-python: PythonFunction): unable to use bundling in BitBucket #14156
* BundlingDockerImage.cp() needs to be explained more in the README #11914