Set businessKey from StartEvent/Form in "flowable-task" App?

Flowable Engine
1

Hi,

I am designing process definitions in flowable-modeler and do baisc testing (with script tasks and/or mock java service tasks/classes) of these in flowable-task.

In the actual application the process instance ist created by “startProcessInstanceById” with a “businessKey” set.

I would also like to set a business key, when starting a process instance out of flowable-task.

Would this be possible from a “start-form”, “start-event” execution listener or somehow different?

The start-form is rendered/shown, before the process instance is created.

Thanks & Regards, Andreas.

2

Hi n0n1ck,

I have just run into a similar need.

I usually include an “Initialise” ScriptTask right at the beginning of my process to initialise, validate and sanitise variables.

One “work-around” is to set the Business Key there using

execution.setBusinessKey("MyBusinessKey");

You can also take it one step further

var businessKey = someInputId;

var businessKeyExists = runtimeService
  .createProcessInstanceQuery()
  .processInstanceBusinessKey(businessKey, execution.processDefinitionKey)
  .count() > 0;

if (businessKeyExists) {
  throw new java.lang.RuntimeException("Process Instance with Business Key already exists");
}

var historicBusinessKeyExists = historyService
  .createHistoricProcessInstanceQuery()
  .processInstanceBusinessKey(businessKey)
  .processDefinitionKey(execution.processDefinitionKey)
  .count() > 0;

if (historicBusinessKeyExists) { 
  throw new java.lang.RuntimeException("Process Instance with Business Key already exists");
}

runtimeService.updateBusinessKey(execution.processInstanceId, businessKey);

If you keep the “Initialise” ScriptTask synchronous, this should throw the Exception back to the user. Now, unfortunately there is a bug in the flowable-ui-task-app/src/main/resources/static/workflow/scripts/services/form-service.js that server errors are not displayed to the user, but once that is fixed the user should have some idea that the business key is not unique.

I fixed the bug locally, and this is what I got.

BusinessKeyAlreadyExists

Kind regards,
Kevin

Pull requests for:

UPDATE: The first version did not take into account historic processes with the same business key. I also neglected the fact that simply setting the business key on the execution variable does update the historic process instance.

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