Architect Data Action: Mapping nested JSON from external REST call to flow variables

Architect & Flows
1

Could someone explain the correct syntax for mapping a nested JSON response from an external REST API in a Genesys Cloud Architect Data Action? I am building a flow that calls a custom CRM endpoint to fetch user details. The HTTP request succeeds with a 200 OK, but the variable mapping fails silently.

The response payload looks like this:

{
 "status": "success",
 "data": {
 "customerId": "12345",
 "tier": "gold"
 }
}

In the Data Action configuration, I am trying to map the response to flow variables. I have tried using $.data.customerId and $.response.data.customerId in the mapping field, but the variable remains empty after the step executes. The documentation suggests JSONPath, but it seems inconsistent with how the Platform SDK handles deserialization.

Is there a specific prefix or syntax required for nested objects in the Architect UI? I am using the standard REST connector with no custom transformations. Any pointers on debugging the mapping expression would be appreciated.

Thanks for the help.

2

Check your variable mapping syntax in the Architect Data Action. When dealing with nested JSON structures, you must traverse the object hierarchy explicitly using dot notation. The silent failure usually occurs because the path defined in the mapping does not perfectly match the structure of the parsed response body.

Here is the step-by-step solution to map the customerId and tier values correctly:

  1. Parse the Response: Ensure your previous HTTP Request action has a variable configured to capture the raw response body. Let’s assume this variable is named crmResponse.
  2. Define Output Variables: In the Data Action, create two new output variables, for example, flow.customerId and flow.tier.
  3. Map the Nested Path: For flow.customerId, the mapping expression must point to the nested object. The correct syntax is:
crmResponse.data.customerId

Similarly, for the tier value:

crmResponse.data.tier

If your CRM response includes an array or deeper nesting, you would extend the dot notation accordingly (e.g., crmResponse.data.profile.tier). A common mistake is trying to access crmResponse.customerId directly, which returns null because customerId is inside the data object.

You can verify the exact structure by logging the crmResponse variable to the flow logs before the Data Action. This allows you to see the actual JSON tree and confirm the path. For more details on data handling in Architect, refer to the Data Actions Documentation.

Always validate that the HTTP request status code is 200 before attempting to parse the body. If the request fails, the crmResponse variable might be empty or contain an error object, leading to mapping errors downstream. Use a Decision block to check the status code first.

3

I typically get around this by ensuring the response is explicitly cast to an object before attempting to traverse nested properties. The silent failure often happens because Architect treats the raw HTTP response as a string, so dot notation fails if the JSON isn’t parsed first.

Here is the robust approach I use in my local dev environments with Terraform-managed flows:

  • Validate the Content-Type: Ensure your external REST endpoint returns application/json. If it returns text/plain, Architect won’t auto-parse it.
  • Cast to Object: In the Data Action, map the Response.Body to a temporary variable using cast(Response.Body, object). This forces the engine to treat the payload as a JSON object.
  • Traverse Nested Keys: Access nested values using dot notation on the casted variable. For your example, use cast(Response.Body, object).data.customerId.

Here is the exact configuration pattern that works for me:

{
 "actionType": "set-variable",
 "variableName": "customerTier",
 "valueExpression": "cast(Response.Body, object).data.tier",
 "dataType": "string"
}

If you are using the Genesys Cloud API directly to debug this, you can inspect the flow execution logs via /api/v2/analytics/flows/realtime/summary to see if the variable was populated. I often spin up a mock API server in Docker to test these mappings locally before pushing to production. This allows me to verify the cast() function behaves as expected without impacting live traffic.

One common gotcha: if the data key might be missing, add a fallback to prevent the action from failing. Use if(cast(Response.Body, object).data != null, cast(Response.Body, object).data.customerId, "unknown"). This ensures your flow remains stable even if the external API returns an unexpected structure.