n8n-code-javascript

To return data from an n8n Code node correctly, you must output an array of objects using the exact [{json: {...}}] return shape. This structure ensures your JavaScript output passes validation and routes cleanly to downstream workflow nodes.

To access webhook payload data safely in an n8n Code node, retrieve values under the correct .body path rather than brittle direct root access. This safe data access pattern prevents runtime errors when handling incoming HTTP requests.

The difference between Run Once for All Items and Run Once for Each Item in n8n JavaScript is how data is accessed: use $input.all() for the entire dataset or $input.item() for individual records. Selecting the correct execution mode ensures proper data aggregation.

Yes, you can make HTTP requests directly within n8n Code node JavaScript by leveraging the built-in $helpers.httpRequest() method. This allows you to perform API calls and data integrations without leaving the code environment.

For time handling in n8n Code nodes, the built-in DateTime object from Luxon is available for date manipulation. You can also use $jmespath() to query and transform JSON data structures within your JavaScript logic.

Your n8n Code node JavaScript fails when processing multiple items if you use incorrect data access methods or fail to output the required array of objects with json payloads. Enforcing proper return shapes and mode selection resolves these runtime errors.