Step Functions: Starting a State Machine via AWS SDK

step-function-execution-example.js

import AWS, { StepFunctions } from 'aws-sdk'
import { v4 } from 'uuid'
import { StartExecutionInput, StartExecutionOutput } from 'aws-sdk/clients/stepfunctions'

interface StateMachineSubmission {
  customerId: string
  traceId: string
}

export class StateMachineService {
  
  private client: StepFunctions

  constructor() {
    this.client = new AWS.StepFunctions()
  }

  private async startExecution(customerId: string, traceId: string) {
    const payload: StateMachineSubmission = { customerId, traceId }
    const params: StartExecutionInput = {
      stateMachineArn: process.env.STATE_MACHINE_ARN,
      input: JSON.stringify(payload),
      name: `${customerId}_${v4().toString()}`,
    }

    const response = await this.client.startExecution(params).promise()
      .catch((err) => {
        console.err(`State machine could not be started [err=${err}, customerId=${customerId}]`)
      })) as StartExecutionOutput
    if (response) {
      console.log(`StateMachine execution has been started [date=${response.startDate}, arn=${response.executionArn}`)
    }
  }
}