Code Execution Node

Overview

The Code Execution node lets you run Python or NodeJS code directly within a workflow to implement custom data processing logic. Compared to other nodes, it offers greater flexibility for complex data transformation, calculation, or formatting tasks — without relying on external services.

Supported Runtimes

Runtime	Best For
Python 3	Data processing, math calculations, text manipulation
NodeJS	JSON processing, string operations, async logic

Configuration

Setting	Description
Runtime	Select the execution environment: Python 3 or NodeJS
Input Variables	Variables referenced from upstream nodes, passed as input parameters. Supports dropdown search
Code Editor	Write custom processing logic; must include a main function as the entry point
Output Variables	Define the field names and types returned after code execution

Code Entry Convention

The code node requires a main function as the entry point. Input variables are passed as parameters, and the return value must be a dictionary (Python) or object (NodeJS).

Python example:

def main(input_text: str) -> dict:
    result = input_text.strip().upper()
    return {
        "output": result,
        "length": len(result)
    }

NodeJS example:

async function main({ inputText }) {
    const result = inputText.trim().toUpperCase();
    return {
        output: result,
        length: result.length
    };
}

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Typical Use Cases

Arithmetic

Perform addition, subtraction, multiplication, division, modulo, or exponentiation on values from upstream nodes.

def main(price: float, quantity: int, discount: float) -> dict:
    subtotal = price * quantity
    total = subtotal * (1 - discount)
    return {
        "subtotal": subtotal,
        "total": round(total, 2)
    }

JSON Transform

Extract fields, restructure, or normalize complex JSON data for downstream nodes.

import json

def main(raw_json: str) -> dict:
    data = json.loads(raw_json)
    return {
        "name": data.get("user", {}).get("name", ""),
        "email": data.get("user", {}).get("contact", {}).get("email", ""),
        "is_active": data.get("status") == "active"
    }

Text Processing

Clean, split, join, or regex-match strings for formatted output or keyword extraction.

import re

def main(raw_text: str) -> dict:
    cleaned = re.sub(r'\s+', ' ', raw_text).strip()
    words = cleaned.split(' ')
    return {
        "cleaned_text": cleaned,
        "word_count": len(words),
        "preview": cleaned[:100]
    }

Date & Time Formatting

Convert timestamps or non-standard date strings to a unified format.

from datetime import datetime

def main(timestamp: int) -> dict:
    dt = datetime.fromtimestamp(timestamp / 1000)
    return {
        "formatted": dt.strftime("%Y-%m-%d %H:%M:%S"),
        "date_only": dt.strftime("%Y-%m-%d"),
        "year": dt.year
    }

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Security Policy

Execution Isolation

Code runs in a sandboxed environment. Each execution is an independent process that is automatically destroyed after completion — no state is retained.

Restricted Capabilities

Restriction	Reason
File system access	Not allowed — prevents data leakage
Network requests	Not allowed — use the HTTP Request node instead
System commands	os.system, subprocess, etc. are blocked
Dynamic code execution	eval, exec, etc. are blocked
Infinite loops	Execution is force-terminated on timeout

Execution Limits

Limit	Value
Max execution time	10 seconds
Max memory	256 MB
Max input variable size	1 MB per variable

Available Libraries

Only built-in standard libraries are available. Third-party packages cannot be installed.

• Python: json, re, math, datetime, hashlib, base64, collections, itertools, etc.
• NodeJS: crypto, path, url, querystring, Buffer, etc.

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Output Variable Configuration

Fields returned by the main function must be declared in the Output Variables panel before they can be referenced by downstream nodes.

Type	Description
String	Text string
Number	Integer or float
Boolean	True/false
Object	JSON object
Array	Array

Undeclared fields in the return value are ignored and not passed downstream.

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Advanced Features

Error Retry — Automatically retry on execution failure.

• Max retries: 10
• Max retry interval: 5000 ms

Exception Handling — Configure a fallback branch when an uncaught exception occurs, avoiding interruption of the entire workflow.

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FAQ

Q: What to do when execution times out?

Check for large-data loops or inefficient algorithms. Use generators for large lists and avoid loading all data at once. Consider filtering or paginating data in upstream nodes.

Q: Output variable not recognized by downstream nodes?

Confirm: (1) the main function returns a dict/object with field names matching the output variable declarations, and (2) the output variable panel has the correct fields and types added.

Q: Can I call other nodes from within the code?

No. The code node is for pure computation only. Interactions with external services (HTTP requests, database queries) must be handled by dedicated nodes, with data passed via variables.

Q: Python or NodeJS?

• Math, regex, data structures → Python
• JSON manipulation, string templates, async logic → NodeJS
• When capabilities are similar, use whichever your team knows better.