Service Task with HTTP REST connector outgoing parameter not getting parsed at Exclusive gateway

Camunda 7 Topics Discussion & Questions
1

Hi,

I have a Service Task with HTTP REST connector. I parsed the response of the HTTP REST using script task and set to connector outgoing parameter.
My goal is to pass that outgoing parameter to validate the condition ${lineStatus == ‘OK’} at Exclusive gateway. But am getting below exception,

[http-nio-8080-exec-10] org.camunda.bpm.engine.rest.exception.RestExceptionHandler.toResponse org.camunda.bpm.engine.rest.exception.RestException: Cannot instantiate process definition CallForwardUsecase:8:7ff2c878-9153-11e7-b400-5cc5d4a39918: ENGINE-02004 No outgoing sequence flow for the element with id 'ExclusiveGateway_1' could be selected for continuing the process.
	at org.camunda.bpm.engine.rest.sub.repository.impl.ProcessDefinitionResourceImpl.submitForm(ProcessDefinitionR

My BPMN file:

Service task connector:

<camunda:outputParameter name="lineStatus">
  <camunda:script scriptFormat="Javascript"><![CDATA[S(response).prop("status")]]></camunda:script>
</camunda:outputParameter>

Exclusive gateway:

<bpmn2:exclusiveGateway id="ExclusiveGateway_1" name="isPhoneAvailable?">
      <bpmn2:incoming>SequenceFlow_4</bpmn2:incoming>
      <bpmn2:outgoing>SequenceFlow_5</bpmn2:outgoing>
      <bpmn2:outgoing>SequenceFlow_7</bpmn2:outgoing>
    </bpmn2:exclusiveGateway>
    <bpmn2:sequenceFlow id="SequenceFlow_5" name="yes" sourceRef="ExclusiveGateway_1" targetRef="ServiceTask_3">
      <bpmn2:conditionExpression xsi:type="bpmn2:tFormalExpression">${lineStatus == 'OK'}</bpmn2:conditionExpression>
    </bpmn2:sequenceFlow>
    <bpmn2:sequenceFlow id="SequenceFlow_7" name="no" sourceRef="ExclusiveGateway_1" targetRef="UserTask_1">
      <bpmn2:conditionExpression xsi:type="bpmn2:tFormalExpression">${lineStatus == 'OKkk'}</bpmn2:conditionExpression>
    </bpmn2:sequenceFlow>
2

Hi,

the exception states that both expressions are false. So the lineStatus is neither OK nor OKkk, I would expect that the lineStatus is not OKkk if something went wrong? Did you check if the variable is set to another value or is it empty?

Cheers,
Sebastian

3

Hi Sebastian,

Its working fine now after making changes In my JS file.

  • I did convert my response key to StringValue() and
  • set the lineStatus to true/false.
  • Condition is ${lineStatus}

var status = api_response.prop(“status”).stringValue();
var status = api_response.prop(“status”).stringValue();
log.info("Status: "+ status);

if(status == “OK”){
var s = true;
log.info("If block s: "+ s);

}
else {
var s = false;
log.info("s***: "+ s);
}

4

Again facing an issue,

05-Sep-2017 16:16:22.003 SEVERE [http-nio-8080-exec-40] org.camunda.commons.logging.BaseLogger.logError ENGINE-16004 Exception while closing command context: condition expression returns null: result is null
org.camunda.bpm.engine.exception.NullValueException: condition expression returns null: result is null

BPM Source:

   <bpmn2:serviceTask id="ServiceTask_2" name="PhoneStatus">
  <bpmn2:extensionElements>
    <camunda:connector>
      <camunda:connectorId>http-connector</camunda:connectorId>
      <camunda:inputOutput>
        <camunda:inputParameter name="url">http://${application.phoneIP}/cgi-bin/api-get_phone_status?passcode=admin</camunda:inputParameter>
        <camunda:inputParameter name="method"><![CDATA[
          GET
        ]]></camunda:inputParameter>
        <camunda:inputParameter name="headers">
          <camunda:map>
            <camunda:entry key="Accept"><![CDATA[
              application/json
            ]]></camunda:entry>
          </camunda:map>
        </camunda:inputParameter>
        <camunda:outputParameter name="phoneStatus">
          <camunda:script scriptFormat="Javascript" resource="phoneStatus.js"/>
        </camunda:outputParameter>
      </camunda:inputOutput>
    </camunda:connector>
  </bpmn2:extensionElements>
  <bpmn2:incoming>SequenceFlow_3</bpmn2:incoming>
  <bpmn2:incoming>SequenceFlow_2</bpmn2:incoming>
  <bpmn2:outgoing>SequenceFlow_4</bpmn2:outgoing>
</bpmn2:serviceTask>
<bpmn2:sequenceFlow id="SequenceFlow_3" name="" sourceRef="ServiceTask_1" targetRef="ServiceTask_2"/>
<bpmn2:sequenceFlow id="SequenceFlow_4" name="" sourceRef="ServiceTask_2" targetRef="ExclusiveGateway_1"/>
<bpmn2:exclusiveGateway id="ExclusiveGateway_1" name="isPhoneAvailable?">
  <bpmn2:incoming>SequenceFlow_4</bpmn2:incoming>
  <bpmn2:outgoing>SequenceFlow_5</bpmn2:outgoing>
  <bpmn2:outgoing>SequenceFlow_7</bpmn2:outgoing>
</bpmn2:exclusiveGateway>
<bpmn2:sequenceFlow id="SequenceFlow_5" name="yes" sourceRef="ExclusiveGateway_1" targetRef="ServiceTask_3">
  <bpmn2:conditionExpression xsi:type="bpmn2:tFormalExpression">${phoneStatus}</bpmn2:conditionExpression>
</bpmn2:sequenceFlow>
<bpmn2:sequenceFlow id="SequenceFlow_7" name="no" sourceRef="ExclusiveGateway_1" targetRef="UserTask_1">
  <bpmn2:conditionExpression xsi:type="bpmn2:tFormalExpression">${!phoneStatus}</bpmn2:conditionExpression>
</bpmn2:sequenceFlow>

JS File:

//parse response variable with camunda-spin
var api_response = S(response);

var status = api_response.prop(“body”).stringValue();
log.info("Status: "+ status);

if(status == “available”){
var s = true;
log.info("If block s: "+ s);

}
else {
var s = false;
log.info("s***: "+ s);
}
connector.setVariable(“phoneStatus”, s);

5

I think your script has to return something which is then saved as the variable phoneStatus defined in the XML. So instead of connector.setVariable("phoneStatus", s); use something like s; instead.

6

Thanks. I will try this.

I have another question about timer event, i have attached a Intermediate Catch event with timer PT10S but the timer event takes more than 50sec. I do not know why it is taking more time than specified. how to overcome this issue?