How to call external JS script?

Developers
1

Dear forum,

I have been searching the forum and could not find any information in this regard. Is it possible for a Task defined in the modeller interface to call an external JS/NodeJS script ? As I see now it is possible to define only an inline script when setting the execution listener/input parameters/output parameters to type Script → Script Format JavaScript. But we would like for the activity to execute an external script.

Is there any possible way of doing this (without too much coding or a reasonable amount of coding) ?

Thank you

2

The Camunda BPMN extensions offers something like that via the resource propery.

<camunda:script scriptFormat="javascript" resource="foo" />

Cf. camunda-bpmn-moddle/camunda.json at master · camunda/camunda-bpmn-moddle · GitHub

image

3

Hi @alecxs86,

maybe it’s the external service task you are looking for: External Tasks | docs.camunda.org.

With @Niklas_Kiefer approach, the java script is executed in the process engine with the Nashorn Javascript implementation.

With external service task, you can use a NodeJs client like this: GitHub - camunda/camunda-external-task-client-js: Implement your BPMN Service Task in NodeJS. to invoke your business logic in JavaScript.

Hope this helps, Ingo

1 Like
4

Thank you for the reply. @Ingo_Richtsmeier

However your solution assumes the external NodeJS client calls the process. I am looking for the other way around. I would like for the process instance to call (execute) a script. Can you confirm such a behaviour is possible ?

Thank you

5

Hi @alecxs86,

This is possible. Have a look at the docs about possible options: https://docs.camunda.org/manual/7.16/user-guide/process-engine/scripting/#script-source

Questions regarding the Camunda Platform and process execution are usually handled in this forum: https://forum.camunda.org

Hope this helps, Ingo