Get variable from the completed process

Camunda 7 Topics Discussion & Questions
1

Hello everybody,

Is there a way to retrieve the variable which was set at a process after the process complete?

Thank you!

2

@Yury, Do you want to retrieve process variables for the completed processes?

3

@aravindhrs yes, I do.
The situation looks something like this

   @PostMapping(value = "/question")
   public ResponseEntity<ResponseToUi> sendQuestion(@RequestBody questionDto questionDto) {
       VariableMap variableMap = Variables
               .putValue("question", questionDto.getQuestion());
       runtimeService.startProcessInstanceByKey("questionProcess", variableMap);
       //during the execution process, I set up a variable which shows me which response I should send to the client
      //retrieve value
       if(*some condition with retrieved value*) {
           throw new CustomException();
       }
       return new ResponseEntity<>(new ResponseToUi(SUCCESS, EMAIL_IS_SENT), HttpStatus.OK);
   }
4

@Yury, I hope this might help you. By using DefaultProcessEngine history service can be accesed like:

HistoryService historyService = BpmPlatform.getDefaultProcessEngine().getHistoryService();

HistoricProcessInstance historicProcessInstance = historyService
	.createHistoricProcessInstanceQuery().processDefinitionKey("processDefinitionKey")
	.processInstanceBusinessKey("processInstanceBusinessKey").finished().singleResult();

List<HistoricVariableInstance> historicVariableInstances =
	historyService.createHistoricVariableInstanceQuery()
		.processDefinitionKey(historicProcessInstance.getProcessDefinitionKey())
		.processInstanceId(historicProcessInstance.getId()).list();

String variableName = historicVariableInstances.get(0).getName();

Object variableValue = historicVariableInstances.get(0).getValue();
5

If you have named process engine, then history service can be accessed like:

BpmPlatform.getProcessEngineService().getProcessEngine("name").getHistoryService();
6

@aravindhrs Thank you!
I will try this solution

7

@Yury, In Spring environment, you can directly access the history service by autowiring.

@Autowired
private HistoryService historyService;

Then,

HistoricProcessInstance historicProcessInstance = historyService
	.createHistoricProcessInstanceQuery().processDefinitionKey("processDefinitionKey")
	.processInstanceBusinessKey("processInstanceBusinessKey").finished().singleResult();

List<HistoricVariableInstance> historicVariableInstances =
	historyService.createHistoricVariableInstanceQuery()
		.processDefinitionKey(historicProcessInstance.getProcessDefinitionKey())
		.processInstanceId(historicProcessInstance.getId()).list();
8