nodejs

Camunda Platform 8 - Get Started - Node.js

This guide explains how to setup a node.js project to automate a process using Camunda Platform 8.

Install dependencies

The open source library zeebe-node provides a Zeebe client.

npm install --save zeebe-node

Create Client

If we want to connect to a Camunda Platform 8 SaaS cluster we need the clusterId from the Clusters details page, a clientId and clientSecret from a client credentials pair.

const { ZBClient } = require('zeebe-node')

const zbc = new ZBClient({
	camundaCloud: {
		clusterId: '365eed98-16c1-4096-bb57-eb8828ed131e',
		clientId: 'GZVO3ALYy~qCcD3MYq~sf0GIszNzLE_z',
		clientSecret: '.RPbZc6q0d6uzRbB4LW.B8lCpsxbBEpmBX0AHQGzINf3.KK9RkzZW1aDaZ-7WYNJ',
	},
})

If you are using a self managed Camunda Platform 8 cluster, you create the client without parameters.

const { ZBClient } = require('zeebe-node')

const zbc = new ZBClient()

Deploy Process and Start Instance

To deploy a process you have to specify the filepath of the BPMN file.

await zbc.deployProcess(['../process/send-email.bpmn'])

To start a new instance you have to specify the bpmnProcessId, i.e. send-email and optionally process variables.

const result = await zbc.createProcessInstance('send-email', {
	message_content: 'Hello from the node.js get started',
})
console.log(result)

For the complete code see the deploy-and-start-instance.js file. You can run it using the following command.

node deploy-and-start-instance.js

Job Worker

To complete a service task, a job worker has to be subscribed the to task type defined in the process, i.e. email.

zbc.createWorker({
	taskType: 'email',
	taskHandler: (job, _, worker) => {
		const { message_content } = job.variables
		worker.log(`Sending email with message content: ${message_content}`)
		job.complete()
	}
})

For the complete code see the email-worker.js file. You can run it using the following command.

node email-worker.js

To make an job available, a user task has to be completed, follow the instructions in the guide.