n8n JavaScript Code Assistant FAQs

Question 1

How do I access data from a previous node in n8n?

Accepted Answer

Use $input.all() to retrieve all items as an array, $input.first() for the first item, or $node["Node Name"].json to reference a specific node in your workflow.

Question 2

How do I access Webhook data in a Code node?

Accepted Answer

Webhook data is nested under the .body property. Instead of $json.email, you should use $json.body.email or $input.first().json.body.email to access the payload correctly.

Question 3

What is the difference between 'Run Once for All Items' and 'Each Item'?

Accepted Answer

'All Items' executes once for the entire dataset, which is faster and better for aggregation. 'Each Item' runs the script separately for every input item, useful for independent per-item logic.

Question 4

Why is my n8n Code node returning a 'No Data' error?

Accepted Answer

n8n requires the Code node to return an array of objects in the specific format: [{json: {...}}]. If you return a raw object, string, or nothing at all, the node will fail.

Question 5

How do I handle dates in n8n Code nodes?

Accepted Answer

n8n includes the Luxon library via the 'DateTime' global variable. You can use it to format dates, perform arithmetic (plus/minus), and parse ISO strings easily within the node.

n8n JavaScript Code Assistant

Key Features

Use Cases

n8n JavaScript Code Assistant

Key Features

Use Cases