Evaluate DMN via API

Hi, I’m investigating evaluating JSONs using the API.


  • a simple DMN, that checks if a json field (“name”) contains the value “Test”
  • a request to …/decision-definition/key/simpleDMN/evaluate with as body:
    "variables": {
        "JSONpayload": {
            "value": "{\"name\": \"thearlaicheachaig \"}",
            "type": "Json"

This is working fine - if I open Cockpit I can check the result. However, the API responds with:
Null key for a Map not allowed in JSON (use a converting NullKeySerializer?) (through reference chain: java.util.ArrayList[0]->java.util.HashMap[“null”])

I would to retrieve the DMN evaluation result with the API as well. Is this possible?

For future reference if someone else finds this. You have to configure the output in the DMN as well.


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