How to use Camunda form variables as input to DMN

[Pushkala]

Hi Team,
Apologies if this question is asked earlier.
I have a requirement like I will get some inputs from the initiate form and using these form variables, I need to define some rules in DMN and the output of the DMN decides what is the next flow.

ie, there is a form field called ‘Country’ in the initiate form, and based on the country input, I need to decide (using rule task) if some validations are required and if yes, that should be routed to a flow. So I am very confused on how can I provide this country form field as input to DMN in the rule task.

Thanks in advance

[StephanHaarmann]

Hi Pushkala,

There are a few things to consider here:

1. We need to understand how form data is linked to process data. When you use Camunda forms, you can add a key to each input field. This key is the variable name. In the following example, we store the user input in the variable countryInput:
   
   
   
   This variable can be used in the process. You can read more about this in our documentation here and here.
2. Next, we need to understand how these process variables can be accessed by DMN decision. Such a decision is called via a business rule task. When you define the input of a decision table, you can define an input variable, e.g., the input for column country is taken from the process variable countryInput:
   
   
   
   Alternatively, you can use the expression field. Read more about it here.

[Pushkala]

Hi @StephanHaarmann
Thank you very much for your quick response.
I have mapped variable key as Input Variable in DMN. I have listed a set of country values as well.
My need is to check a validation is required or not for these countries( a boolean field which indicates yes or no) and I am getting the following issue

I have mapped input variable here

These are my set of sample rules( eg, if country is Malaysia, autodocValidation=true)
I have added the rule task after start event. I am getting the error:

Can you kindly help me on what went wrong in my rule definition.

[StephanHaarmann]

Hi @Pushkala,
In FEEL and DMN Decision Tables, strings must be sournded by qotation marks.
So instead of Malaysia, Germany, etc. write "Malaysia", "Germany"…

[Pushkala]

@StephanHaarmann Thank you very much. It worked