"Parameters" Parameter for Step Functions Tasks

[rrhodes]

Prior to CDK 0.32.0, I defined a Step Functions task to invoke a Lambda function passing in a couple of parameters:

import stepFunctions = require('@aws-cdk/aws-stepfunctions');

const unknownChannelTask = new stepFunctions.Task(this, "UnknownChannel", {
            resource: resultsLambda,
            parameters: {
                "data.$": "$",
                "status": "UNKNOWN_CHANNEL"
            }
        });

These parameters included existing data $ in the Step Functions, as well as introducing status = UNKNOWN_CHANNEL.

From CDK 0.32.0, this is refactored to

import stepFunctions = require('@aws-cdk/aws-stepfunctions');
import stepFunctionsTasks = require('@aws-cdk/aws-stepfunctions-tasks');

 const unknownChannelTask = new stepFunctions.Task(this, 'UnknownChannel', {
            task: new stepFunctionsTasks.InvokeFunction(resultsLambda)
        });

Now I think I'm no longer able to provide the parameters in this task definition. I've extended the InvokeFunction class to workaround this

import { InvokeFunction } from "@aws-cdk/aws-stepfunctions-tasks";
import { IStepFunctionsTask, StepFunctionsTaskProperties, Task } from "@aws-cdk/aws-stepfunctions";
import { IFunction } from "@aws-cdk/aws-lambda";

export class InvokeFunctionWithParameters extends InvokeFunction implements IStepFunctionsTask {
    parameters: { [key: string]: string };

    constructor(lambdaFunction: IFunction, parameters: { [key: string]: string }) {
        super(lambdaFunction);
        this.parameters = parameters;
    }

    bind(task: Task): StepFunctionsTaskProperties {
        return {
            ...super.bind(task),
            parameters: this.parameters,
        };
    }
}

Am I missing a simpler approach to this? If not, would it be possible to add support for parameters to the InvokeFunction class directly, rather than having to extend the class like above?