n8n-code-javascript

To process webhook payloads in n8n Code nodes, access the incoming data strictly via the `.body` property and use `$input.all()` for batch processing. Return an array of objects containing a `json` field to ensure the output matches n8n's expected data structure.

The best way to structure returns in n8n workflows is to always return an array of objects where each object contains a `json` field. This strict return format prevents downstream node errors and ensures your data transformations integrate smoothly with the rest of the pipeline.

To make HTTP API calls inside an n8n Code node, use the built-in `$helpers.httpRequest()` helper function. This allows you to perform reliable API interactions directly within your JavaScript code without needing external nodes or custom boilerplate.

Use Run Once for All Items in n8n as the default workflow for batch data transformations and multi-source aggregation. Switch to Run Once for Each Item only when you need isolated, per-item logic, utilizing `$input.first()` or `$input.item` for specific data access.

To handle date and time transformations in n8n JavaScript, use the built-in `DateTime` object provided by the Luxon library. This allows you to perform robust date parsing, formatting, and arithmetic operations directly within your Code node transformations.

n8n Code node data transformations often fail on null values due to unhandled data access. Implement null checks, use try-catch blocks for error handling, and apply safe data access patterns with `$jmespath()` to query JSON and prevent workflow failures.