Custom code block output not working

Data Hub Data Hub
1

Hi there HubSpot community. I’m new to Data Hub and hoping someone can help with an issue we’re having.

We have a custom code block that when it runs it should:

  • take the deal ID of the enrolled deal
  • look to see what deals are associated with the enrolled deal (they’ll only be one)
  • return the deal ID of the associated deal as a data output; parentDealId

However, when ever the code block runs the out put always returns this error message:

‘Not defined in code’.

Below is the code we’re using and a screenshot of the setup and the results output. Thank you for your help!

exports.main = async (event, callback) => {
const dealId = String(event.inputFields.hs_object_id || ‘’);
const TOKEN = process.env.Account_API_Key;

if (!dealId || !TOKEN) return callback({ parentDealId: ‘’ });

try {
const url = `https://api.hubapi.com/crm/v4/objects/deals/${dealId}/associations/deal\`;
const res = await fetch(url, {
method: ‘GET’,
headers: { Authorization: `Bearer ${TOKEN}`, Accept: ‘application/json’ }
});

if (!res.ok) return callback({ parentDealId: ‘’ });

const data = await res.json();
const parentDealId = data?.results?.[0]?.toObjectId
? String(data.results[0].toObjectId)
: ‘’;

return callback({ parentDealId });
} catch (e) {
return callback({ parentDealId: ‘’ });
}
};

code step 2.jpg
code step 2.jpg1184×1547 148 KB

Code step 1.png
Code step 1.png1439×932 194 KB

2

I have managed to sort this. The code needed an output field wrapper:

return callback({ outputFields: { parentDealId } });

3

Hey, @BVowles :waving_hand: Were you able to make any progress here? — Jaycee

4

Hi @BVowles , yep, this one is super common when you’re new to Data Hub and custom code actions. The “Not defined in code” message almost always means HubSpot didn’t see the output in the exact structure it expects, or the output field name in the action UI doesn’t match what you returned. In HubSpot custom code actions, outputs need to be returned under the outputFields wrapper, like this:

return callback({ outputFields: { parentDealId } });

Without that wrapper, HubSpot logs the value in execution, but the workflow UI treats it as “not produced,” so your downstream steps show “Not defined in code.” HubSpot’s doc calls out this output contract pretty explicitly (Workflows | Custom Code Actions - HubSpot docs )

One more thing to double-check: in the action’s “Outputs” section, did you create an output with the internal name exactly parentDealId (same casing), and not parent_deal_id or similar? A tiny mismatch there will produce the same symptom.

Your fetch call to the associations endpoint is fine for Node 20, and your secret usage looks correct as long as the secret key name in the UI is exactly Account_API_Key. If you want to stay fully “HubSpot SDK-native” later, you can also fetch associations via the CRM Associations API (Accounts Dashboard | HubSpot )

Glad you got it sorted.