Set / Edit Fields
The Set node (Edit Fields) is your primary tool for data manipulation short of writing Code. It allows you to inject static strings, map dynamic variables from previous steps, or completely replace the incoming JSON array with a fresh, strictly-defined structure.
What can you do with Set / Edit Fields?
Variable Declaration & Mapping
Instantiate completely new fields, hardcode required API keys, or cleanly map deep-nested object properties into simple, flat keys for easier consumption.
Strict Data Overwriting
Choose to cautiously append new properties retaining old historical data, or brutally overwrite the JSON object keeping only the specific fields you explicitly define.
Explicit Type Casting
Forcefully convert ambiguous incoming String integers (like "42") into explicit Number types, or Strings to Booleans, which is often crucial for strict API targets.
Detailed Usage & Configuration
The Set / Edit Fields Node is your primary tool for surgical data mapping and JSON restructuring within the workflow without resorting to programmatic Javascript.
1. Injecting Constants & Mappings
You can quickly inject globally required constants (e.g., hardcoding a system_source: "nLink" field directly into the payload array) or remap deeply nested variables (e.g., taking an incoming {{ $json.customer.data.relationships.email }} and cleanly mapping it to a flat new property named just email).
2. Data Retention vs. Overwriting
You control execution completely using two primary retention modes:
- Keep Existing Data (Append): Cautiously append your newly created custom fields alongside the previously existing massive JSON payload. Excellent for simple variable injection.
- Discard Data (Overwrite): Brutally wipe the entire incoming JSON object from memory and construct a strictly defined JSON structure populated solely with the fields you explicitly configure in this node. Crucial for creating strict schemas right before a Database HTTP POST request.