Version: latest

Variables and incidents

Every workflow instance created for the workflow model used in the Getting Started tutorial requires an orderValue so that the XOR gateway evaluation will happen properly.

Let’s look at a case where orderValue is present but was set as a string, but our order-process.bpmn model requires an integer in order to properly evaluate the orderValue and route the instance.


./bin/zbctl --insecure create instance order-process --variables '{"orderId": "1234", "orderValue":"99"}'


./bin/zbctl.darwin --insecure create instance order-process --variables '{"orderId": "1234", "orderValue":"99"}'

Windows (Powershell)

./bin/zbctl.exe --insecure create instance order-process --variables '{\"orderId\": \"1234\", \
"orderValue\": \"99\"}'

To advance the instance to our XOR gateway, we’ll quickly create a job worker to complete the Initiate Payment task:


./bin/zbctl --insecure create worker initiate-payment --handler cat


./bin/zbctl.darwin --insecure create worker initiate-payment --handler cat

Windows (Powershell)

./bin/zbctl.exe --insecure create worker initiate-payment --handler "findstr .*"

And we’ll publish a message that will be correlated with the instance so we can advance past the Payment Received intermediate message catch event:


./bin/zbctl --insecure publish message "payment-received" --correlationKey="1234"


./bin/zbctl.darwin --insecure publish message "payment-received" --correlationKey="1234"

Windows (Powershell)

./bin/zbctl.exe --insecure publish message "payment-received" --correlationKey="1234"

In the Operate interface, you should now see that the workflow instance has an incident, which means there’s a problem with workflow execution that needs to be fixed before the workflow instance can progress to the next step.


Operate provides tools for diagnosing and resolving incidents. Let’s go through incident diagnosis and resolution step-by-step.

When we inspect the workflow instance, we can see exactly what our incident is: Expected to evaluate condition 'orderValue>=100' successfully, but failed because: Cannot compare values of different types: STRING and INTEGER


We have enough information to know that to resolve this incident, we need to edit the orderValue variable so that it’s an integer. To do so, first click on the edit icon next to the variable you’d like to edit.


Next, edit the variable by removing the quotation marks from the orderValue value. Then click on the checkmark icon to save the change.

We were able to solve this particular problem by editing a variable, but it’s worth noting that you can also add a variable if a variable is missing from a workflow instance altogether.


There’s one last step we need to take: initiating a “retry” of the workflow instance. There are two places on the workflow instance page where you can initiate a retry:


You should now see that the incident has been resolved, and the workflow instance has progressed to the next step. Well done!


If you’d like to complete the workflow instance, you can create a worker for the Ship Without Insurance task:


./bin/zbctl --insecure create worker ship-without-insurance --handler cat


./bin/zbctl.darwin --insecure create worker ship-without-insurance --handler cat

Windows (Powershell)

./bin/zbctl.exe --insecure create worker ship-without-insurance --handler "findstr .*"

The completed workflow instance with the path taken: