n8n-code-javascript
Write and debug JavaScript code in n8n Code nodes with proper data access and return formatting.
- Supports two execution modes: "Run Once for All Items" (recommended for 95% of use cases) and "Run Once for Each Item" for specialized per-item logic
- Access data via
$input.all(),$input.first(), or$input.item; always return array format[{json: {...}}] - Built-in helpers include
$helpers.httpRequest()for HTTP calls, DateTime (Luxon) for date operations, and$jmespath()for JSON querying - Critical gotcha: webhook data is nested under
.bodyproperty, not at root level; common mistakes include missing return statements, incorrect return format, and expression syntax confusion
JavaScript Code Node
Expert guidance for writing JavaScript code in n8n Code nodes.
Quick Start
// Basic template for Code nodes
const items = $input.all();
// Process data
const processed = items.map(item => ({
json: {
...item.json,
processed: true,
timestamp: new Date().toISOString()
}
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