AWS CDK(v2) BatchSubmitJob in StepFunctions to dynamically overwrite commands from Context and Input

Introduction

When executing AWSBatch from StepFunctions in AWS CDK, it is convenient to use BatchSubmitJob, but I could not find out how to overwrite containerOverrides.command, so I have written it down.

Version

• aws-cdk: 2.20.0

How to dynamically overwrite command from Context or Input with BatchSubmitJob

There is a aws_stepfunctions.JsonPath, and if string[] is an expected parameter, you can use JsonPath.listAt(JSON_PATH). There are also JsonPath.numberAt(JSON_PATH) and stringAt().

Thus, for example, you can write as followings.

Note that if the specified JSON_PATH is not found in the input JSON, an error will occur.

import {
  aws_stepfunctions as sfn,
  aws_stepfunctions_tasks as tasks,
} from "aws-cdk-lib";

export class MyAwesomeStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);
    // ...
    const batchTask = new tasks.BatchSubmitJob(this, `SubmitJobTask`, {
    jobDefinitionArn: JOB_DEF_ARN,
    jobName: "SubmitJob",
    jobQueueArn: JOB_QUEUE_ARN,
    containerOverrides: {
        command: sfn.JsonPath.listAt("$.commands"),
    },
    attempts: sfn.JsonPath.numberAt("$.attempts"),
    });
    // ...
  }

JSON example of input

{
  "commands": ["echo", "hello"],
  "attempts": 3
}

Afterward

I have a hard time pinpointing this kind of information in a search.